X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/c801d85f158c4cba50b588807daabdcbd0ed3853..783d8c1131679d4032266ea7913e95a756808e8f:/src/png/pngrtran.c diff --git a/src/png/pngrtran.c b/src/png/pngrtran.c index 885af53905..b5e8f1a26f 100644 --- a/src/png/pngrtran.c +++ b/src/png/pngrtran.c @@ -1,108 +1,87 @@ /* pngrtran.c - transforms the data in a row for PNG readers * - * libpng 1.0.1 - * For conditions of distribution and use, see copyright notice in png.h - * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. - * Copyright (c) 1996, 1997 Andreas Dilger - * Copyright (c) 1998, Glenn Randers-Pehrson - * March 15, 1998 + * Last changed in libpng 1.4.2 [May 6, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) * - * This file contains functions optionally called by an application + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file contains functions optionally called by an application * in order to tell libpng how to handle data when reading a PNG. - * Transformations which are used in both reading and writing are + * Transformations that are used in both reading and writing are * in pngtrans.c. */ -#define PNG_INTERNAL +#define PNG_NO_PEDANTIC_WARNINGS #include "png.h" - -#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED -/* With these routines, we avoid an integer divide, which will be slower on - * many machines. However, it does take more operations than the corresponding - * divide method, so it may be slower on some RISC systems. There are two - * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. - * - * Note that the rounding factors are NOT supposed to be the same! 128 and - * 32768 are correct for the NODIV code; 127 and 32767 are correct for the - * standard method. - * - * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] - */ - - /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ -# define png_composite(composite, fg, alpha, bg) \ - { png_uint_16 temp = ((png_uint_16)(fg) * (png_uint_16)(alpha) + \ - (png_uint_16)(bg)*(png_uint_16)(255 - \ - (png_uint_16)(alpha)) + (png_uint_16)128); \ - (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } -# define png_composite_16(composite, fg, alpha, bg) \ - { png_uint_32 temp = ((png_uint_32)(fg) * (png_uint_32)(alpha) + \ - (png_uint_32)(bg)*(png_uint_32)(65535L - \ - (png_uint_32)(alpha)) + (png_uint_32)32768L); \ - (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } - -#else /* standard method using integer division */ - - /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ -# define png_composite(composite, fg, alpha, bg) \ - (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ - (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ - (png_uint_16)127) / 255) -# define png_composite_16(composite, fg, alpha, bg) \ - (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ - (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \ - (png_uint_32)32767) / (png_uint_32)65535L) - -#endif /* ?PNG_READ_COMPOSITE_NODIV_SUPPORTED */ - +#ifdef PNG_READ_SUPPORTED +#include "pngpriv.h" /* Set the action on getting a CRC error for an ancillary or critical chunk. */ -void +void PNGAPI png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action) { - png_debug(1, "in png_set_crc_action\n"); + png_debug(1, "in png_set_crc_action"); + + if (png_ptr == NULL) + return; + /* Tell libpng how we react to CRC errors in critical chunks */ switch (crit_action) { - case PNG_CRC_NO_CHANGE: /* leave setting as is */ + case PNG_CRC_NO_CHANGE: /* Leave setting as is */ break; - case PNG_CRC_WARN_USE: /* warn/use data */ + + case PNG_CRC_WARN_USE: /* Warn/use data */ png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE; break; - case PNG_CRC_QUIET_USE: /* quiet/use data */ + + case PNG_CRC_QUIET_USE: /* Quiet/use data */ png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE | PNG_FLAG_CRC_CRITICAL_IGNORE; break; - case PNG_CRC_WARN_DISCARD: /* not a valid action for critical data */ - png_warning(png_ptr, "Can't discard critical data on CRC error."); - case PNG_CRC_ERROR_QUIT: /* error/quit */ + + case PNG_CRC_WARN_DISCARD: /* Not a valid action for critical data */ + png_warning(png_ptr, + "Can't discard critical data on CRC error"); + case PNG_CRC_ERROR_QUIT: /* Error/quit */ + case PNG_CRC_DEFAULT: default: png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; break; } + /* Tell libpng how we react to CRC errors in ancillary chunks */ switch (ancil_action) { - case PNG_CRC_NO_CHANGE: /* leave setting as is */ + case PNG_CRC_NO_CHANGE: /* Leave setting as is */ break; - case PNG_CRC_WARN_USE: /* warn/use data */ + + case PNG_CRC_WARN_USE: /* Warn/use data */ png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE; break; - case PNG_CRC_QUIET_USE: /* quiet/use data */ + + case PNG_CRC_QUIET_USE: /* Quiet/use data */ png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN; break; - case PNG_CRC_ERROR_QUIT: /* error/quit */ + + case PNG_CRC_ERROR_QUIT: /* Error/quit */ png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_NOWARN; break; - case PNG_CRC_WARN_DISCARD: /* warn/discard data */ + + case PNG_CRC_WARN_DISCARD: /* Warn/discard data */ + case PNG_CRC_DEFAULT: default: png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; @@ -110,14 +89,18 @@ png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action) } } -#if defined(PNG_READ_BACKGROUND_SUPPORTED) -/* handle alpha and tRNS via a background color */ -void +#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \ + defined(PNG_FLOATING_POINT_SUPPORTED) +/* Handle alpha and tRNS via a background color */ +void PNGAPI png_set_background(png_structp png_ptr, png_color_16p background_color, int background_gamma_code, int need_expand, double background_gamma) { - png_debug(1, "in png_set_background\n"); + png_debug(1, "in png_set_background"); + + if (png_ptr == NULL) + return; if (background_gamma_code == PNG_BACKGROUND_GAMMA_UNKNOWN) { png_warning(png_ptr, "Application must supply a known background gamma"); @@ -126,39 +109,45 @@ png_set_background(png_structp png_ptr, png_ptr->transformations |= PNG_BACKGROUND; png_memcpy(&(png_ptr->background), background_color, - sizeof(png_color_16)); + png_sizeof(png_color_16)); png_ptr->background_gamma = (float)background_gamma; png_ptr->background_gamma_type = (png_byte)(background_gamma_code); png_ptr->transformations |= (need_expand ? PNG_BACKGROUND_EXPAND : 0); } #endif -#if defined(PNG_READ_16_TO_8_SUPPORTED) -/* strip 16 bit depth files to 8 bit depth */ -void +#ifdef PNG_READ_16_TO_8_SUPPORTED +/* Strip 16 bit depth files to 8 bit depth */ +void PNGAPI png_set_strip_16(png_structp png_ptr) { - png_debug(1, "in png_set_strip_16\n"); + png_debug(1, "in png_set_strip_16"); + + if (png_ptr == NULL) + return; png_ptr->transformations |= PNG_16_TO_8; } #endif -#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) -void +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED +void PNGAPI png_set_strip_alpha(png_structp png_ptr) { - png_debug(1, "in png_set_strip_alpha\n"); - png_ptr->transformations |= PNG_STRIP_ALPHA; + png_debug(1, "in png_set_strip_alpha"); + + if (png_ptr == NULL) + return; + png_ptr->flags |= PNG_FLAG_STRIP_ALPHA; } #endif -#if defined(PNG_READ_DITHER_SUPPORTED) -/* Dither file to 8 bit. Supply a palette, the current number +#ifdef PNG_READ_QUANTIZE_SUPPORTED +/* Quantize file to 8 bit. Supply a palette, the current number * of elements in the palette, the maximum number of elements * allowed, and a histogram if possible. If the current number * of colors is greater then the maximum number, the palette will be - * modified to fit in the maximum number. "full_dither" indicates - * whether we need a dithering cube set up for RGB images, or if we + * modified to fit in the maximum number. "full_quantize" indicates + * whether we need a quantizeing cube set up for RGB images, or if we * simply are reducing the number of colors in a paletted image. */ @@ -171,22 +160,25 @@ typedef struct png_dsort_struct typedef png_dsort FAR * png_dsortp; typedef png_dsort FAR * FAR * png_dsortpp; -void -png_set_dither(png_structp png_ptr, png_colorp palette, +void PNGAPI +png_set_quantize(png_structp png_ptr, png_colorp palette, int num_palette, int maximum_colors, png_uint_16p histogram, - int full_dither) + int full_quantize) { - png_debug(1, "in png_set_dither\n"); - png_ptr->transformations |= PNG_DITHER; + png_debug(1, "in png_set_quantize"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_QUANTIZE; - if (!full_dither) + if (!full_quantize) { int i; - png_ptr->dither_index = (png_bytep)png_malloc(png_ptr, - (png_uint_32)(num_palette * sizeof (png_byte))); + png_ptr->quantize_index = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); for (i = 0; i < num_palette; i++) - png_ptr->dither_index[i] = (png_byte)i; + png_ptr->quantize_index[i] = (png_byte)i; } if (num_palette > maximum_colors) @@ -194,40 +186,42 @@ png_set_dither(png_structp png_ptr, png_colorp palette, if (histogram != NULL) { /* This is easy enough, just throw out the least used colors. - Perhaps not the best solution, but good enough. */ + * Perhaps not the best solution, but good enough. + */ int i; - png_bytep sort; - /* initialize an array to sort colors */ - sort = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_palette - * sizeof (png_byte))); + /* Initialize an array to sort colors */ + png_ptr->quantize_sort = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); - /* initialize the sort array */ + /* Initialize the quantize_sort array */ for (i = 0; i < num_palette; i++) - sort[i] = (png_byte)i; + png_ptr->quantize_sort[i] = (png_byte)i; /* Find the least used palette entries by starting a - bubble sort, and running it until we have sorted - out enough colors. Note that we don't care about - sorting all the colors, just finding which are - least used. */ + * bubble sort, and running it until we have sorted + * out enough colors. Note that we don't care about + * sorting all the colors, just finding which are + * least used. + */ for (i = num_palette - 1; i >= maximum_colors; i--) { - int done; /* to stop early if the list is pre-sorted */ + int done; /* To stop early if the list is pre-sorted */ int j; done = 1; for (j = 0; j < i; j++) { - if (histogram[sort[j]] < histogram[sort[j + 1]]) + if (histogram[png_ptr->quantize_sort[j]] + < histogram[png_ptr->quantize_sort[j + 1]]) { png_byte t; - t = sort[j]; - sort[j] = sort[j + 1]; - sort[j + 1] = t; + t = png_ptr->quantize_sort[j]; + png_ptr->quantize_sort[j] = png_ptr->quantize_sort[j + 1]; + png_ptr->quantize_sort[j + 1] = t; done = 0; } } @@ -235,59 +229,61 @@ png_set_dither(png_structp png_ptr, png_colorp palette, break; } - /* swap the palette around, and set up a table, if necessary */ - if (full_dither) + /* Swap the palette around, and set up a table, if necessary */ + if (full_quantize) { - int j; + int j = num_palette; - /* put all the useful colors within the max, but don't - move the others */ - for (i = 0, j = num_palette; i < maximum_colors; i++) + /* Put all the useful colors within the max, but don't + * move the others. + */ + for (i = 0; i < maximum_colors; i++) { - if ((int)sort[i] >= maximum_colors) + if ((int)png_ptr->quantize_sort[i] >= maximum_colors) { do j--; - while ((int)sort[j] >= maximum_colors); + while ((int)png_ptr->quantize_sort[j] >= maximum_colors); palette[i] = palette[j]; } } } else { - int j; + int j = num_palette; - /* move all the used colors inside the max limit, and - develop a translation table */ - for (i = 0, j = num_palette; i < maximum_colors; i++) + /* Move all the used colors inside the max limit, and + * develop a translation table. + */ + for (i = 0; i < maximum_colors; i++) { - /* only move the colors we need to */ - if ((int)sort[i] >= maximum_colors) + /* Only move the colors we need to */ + if ((int)png_ptr->quantize_sort[i] >= maximum_colors) { png_color tmp_color; do j--; - while ((int)sort[j] >= maximum_colors); + while ((int)png_ptr->quantize_sort[j] >= maximum_colors); tmp_color = palette[j]; palette[j] = palette[i]; palette[i] = tmp_color; - /* indicate where the color went */ - png_ptr->dither_index[j] = (png_byte)i; - png_ptr->dither_index[i] = (png_byte)j; + /* Indicate where the color went */ + png_ptr->quantize_index[j] = (png_byte)i; + png_ptr->quantize_index[i] = (png_byte)j; } } - /* find closest color for those colors we are not using */ + /* Find closest color for those colors we are not using */ for (i = 0; i < num_palette; i++) { - if ((int)png_ptr->dither_index[i] >= maximum_colors) + if ((int)png_ptr->quantize_index[i] >= maximum_colors) { int min_d, k, min_k, d_index; - /* find the closest color to one we threw out */ - d_index = png_ptr->dither_index[i]; + /* Find the closest color to one we threw out */ + d_index = png_ptr->quantize_index[i]; min_d = PNG_COLOR_DIST(palette[d_index], palette[0]); for (k = 1, min_k = 0; k < maximum_colors; k++) { @@ -301,61 +297,58 @@ png_set_dither(png_structp png_ptr, png_colorp palette, min_k = k; } } - /* point to closest color */ - png_ptr->dither_index[i] = (png_byte)min_k; + /* Point to closest color */ + png_ptr->quantize_index[i] = (png_byte)min_k; } } } - png_free(png_ptr, sort); + png_free(png_ptr, png_ptr->quantize_sort); + png_ptr->quantize_sort = NULL; } else { /* This is much harder to do simply (and quickly). Perhaps - we need to go through a median cut routine, but those - don't always behave themselves with only a few colors - as input. So we will just find the closest two colors, - and throw out one of them (chosen somewhat randomly). - [I don't understand this at all, so if someone wants to - work on improving it, be my guest - AED] - */ + * we need to go through a median cut routine, but those + * don't always behave themselves with only a few colors + * as input. So we will just find the closest two colors, + * and throw out one of them (chosen somewhat randomly). + * [We don't understand this at all, so if someone wants to + * work on improving it, be our guest - AED, GRP] + */ int i; int max_d; int num_new_palette; + png_dsortp t; png_dsortpp hash; - png_bytep index_to_palette; - /* where the original index currently is in the palette */ - png_bytep palette_to_index; - /* which original index points to this palette color */ - - /* initialize palette index arrays */ - index_to_palette = (png_bytep)png_malloc(png_ptr, - (png_uint_32)(num_palette * sizeof (png_byte))); - palette_to_index = (png_bytep)png_malloc(png_ptr, - (png_uint_32)(num_palette * sizeof (png_byte))); - - /* initialize the sort array */ + + t = NULL; + + /* Initialize palette index arrays */ + png_ptr->index_to_palette = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); + png_ptr->palette_to_index = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); + + /* Initialize the sort array */ for (i = 0; i < num_palette; i++) { - index_to_palette[i] = (png_byte)i; - palette_to_index[i] = (png_byte)i; + png_ptr->index_to_palette[i] = (png_byte)i; + png_ptr->palette_to_index[i] = (png_byte)i; } - hash = (png_dsortpp)png_malloc(png_ptr, (png_uint_32)(769 * - sizeof (png_dsortp))); - for (i = 0; i < 769; i++) - hash[i] = NULL; -/* png_memset(hash, 0, 769 * sizeof (png_dsortp)); */ + hash = (png_dsortpp)png_calloc(png_ptr, (png_uint_32)(769 * + png_sizeof(png_dsortp))); num_new_palette = num_palette; - /* initial wild guess at how far apart the farthest pixel - pair we will be eliminating will be. Larger - numbers mean more areas will be allocated, Smaller - numbers run the risk of not saving enough data, and - having to do this all over again. - - I have not done extensive checking on this number. - */ + /* Initial wild guess at how far apart the farthest pixel + * pair we will be eliminating will be. Larger + * numbers mean more areas will be allocated, Smaller + * numbers run the risk of not saving enough data, and + * having to do this all over again. + * + * I have not done extensive checking on this number. + */ max_d = 96; while (num_new_palette > maximum_colors) @@ -372,18 +365,22 @@ png_set_dither(png_structp png_ptr, png_colorp palette, if (d <= max_d) { - png_dsortp t; - t = (png_dsortp)png_malloc(png_ptr, (png_uint_32)(sizeof - (png_dsort))); + t = (png_dsortp)png_malloc_warn(png_ptr, + (png_uint_32)(png_sizeof(png_dsort))); + if (t == NULL) + break; t->next = hash[d]; t->left = (png_byte)i; t->right = (png_byte)j; hash[d] = t; } } + if (t == NULL) + break; } + if (t != NULL) for (i = 0; i <= max_d; i++) { if (hash[i] != NULL) @@ -392,12 +389,14 @@ png_set_dither(png_structp png_ptr, png_colorp palette, for (p = hash[i]; p; p = p->next) { - if ((int)index_to_palette[p->left] < num_new_palette && - (int)index_to_palette[p->right] < num_new_palette) + if ((int)png_ptr->index_to_palette[p->left] + < num_new_palette && + (int)png_ptr->index_to_palette[p->right] + < num_new_palette) { int j, next_j; - if (num_new_palette & 1) + if (num_new_palette & 0x01) { j = p->left; next_j = p->right; @@ -409,31 +408,34 @@ png_set_dither(png_structp png_ptr, png_colorp palette, } num_new_palette--; - palette[index_to_palette[j]] = palette[num_new_palette]; - if (!full_dither) + palette[png_ptr->index_to_palette[j]] + = palette[num_new_palette]; + if (!full_quantize) { int k; for (k = 0; k < num_palette; k++) { - if (png_ptr->dither_index[k] == - index_to_palette[j]) - png_ptr->dither_index[k] = - index_to_palette[next_j]; - if ((int)png_ptr->dither_index[k] == + if (png_ptr->quantize_index[k] == + png_ptr->index_to_palette[j]) + png_ptr->quantize_index[k] = + png_ptr->index_to_palette[next_j]; + if ((int)png_ptr->quantize_index[k] == num_new_palette) - png_ptr->dither_index[k] = - index_to_palette[j]; + png_ptr->quantize_index[k] = + png_ptr->index_to_palette[j]; } } - index_to_palette[palette_to_index[num_new_palette]] = - index_to_palette[j]; - palette_to_index[index_to_palette[j]] = - palette_to_index[num_new_palette]; + png_ptr->index_to_palette[png_ptr->palette_to_index + [num_new_palette]] = png_ptr->index_to_palette[j]; + png_ptr->palette_to_index[png_ptr->index_to_palette[j]] + = png_ptr->palette_to_index[num_new_palette]; - index_to_palette[j] = (png_byte)num_new_palette; - palette_to_index[num_new_palette] = (png_byte)j; + png_ptr->index_to_palette[j] = + (png_byte)num_new_palette; + png_ptr->palette_to_index[num_new_palette] = + (png_byte)j; } if (num_new_palette <= maximum_colors) break; @@ -447,13 +449,9 @@ png_set_dither(png_structp png_ptr, png_colorp palette, { if (hash[i] != NULL) { - png_dsortp p; - - p = hash[i]; + png_dsortp p = hash[i]; while (p) { - png_dsortp t; - t = p->next; png_free(png_ptr, p); p = t; @@ -464,8 +462,10 @@ png_set_dither(png_structp png_ptr, png_colorp palette, max_d += 96; } png_free(png_ptr, hash); - png_free(png_ptr, palette_to_index); - png_free(png_ptr, index_to_palette); + png_free(png_ptr, png_ptr->palette_to_index); + png_free(png_ptr, png_ptr->index_to_palette); + png_ptr->palette_to_index = NULL; + png_ptr->index_to_palette = NULL; } num_palette = maximum_colors; } @@ -475,61 +475,53 @@ png_set_dither(png_structp png_ptr, png_colorp palette, } png_ptr->num_palette = (png_uint_16)num_palette; - if (full_dither) + if (full_quantize) { int i; - int total_bits, num_red, num_green, num_blue; - png_size_t num_entries; png_bytep distance; + int total_bits = PNG_QUANTIZE_RED_BITS + PNG_QUANTIZE_GREEN_BITS + + PNG_QUANTIZE_BLUE_BITS; + int num_red = (1 << PNG_QUANTIZE_RED_BITS); + int num_green = (1 << PNG_QUANTIZE_GREEN_BITS); + int num_blue = (1 << PNG_QUANTIZE_BLUE_BITS); + png_size_t num_entries = ((png_size_t)1 << total_bits); - total_bits = PNG_DITHER_RED_BITS + PNG_DITHER_GREEN_BITS + - PNG_DITHER_BLUE_BITS; - - num_red = (1 << PNG_DITHER_RED_BITS); - num_green = (1 << PNG_DITHER_GREEN_BITS); - num_blue = (1 << PNG_DITHER_BLUE_BITS); - num_entries = ((png_size_t)1 << total_bits); - - png_ptr->palette_lookup = (png_bytep )png_malloc(png_ptr, - (png_uint_32)(num_entries * sizeof (png_byte))); - - png_memset(png_ptr->palette_lookup, 0, num_entries * sizeof (png_byte)); + png_ptr->palette_lookup = (png_bytep )png_calloc(png_ptr, + (png_uint_32)(num_entries * png_sizeof(png_byte))); distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries * - sizeof(png_byte))); - - png_memset(distance, 0xff, num_entries * sizeof(png_byte)); + png_sizeof(png_byte))); + png_memset(distance, 0xff, num_entries * png_sizeof(png_byte)); for (i = 0; i < num_palette; i++) { - int r, g, b, ir, ig, ib; - - r = (palette[i].red >> (8 - PNG_DITHER_RED_BITS)); - g = (palette[i].green >> (8 - PNG_DITHER_GREEN_BITS)); - b = (palette[i].blue >> (8 - PNG_DITHER_BLUE_BITS)); + int ir, ig, ib; + int r = (palette[i].red >> (8 - PNG_QUANTIZE_RED_BITS)); + int g = (palette[i].green >> (8 - PNG_QUANTIZE_GREEN_BITS)); + int b = (palette[i].blue >> (8 - PNG_QUANTIZE_BLUE_BITS)); for (ir = 0; ir < num_red; ir++) { - int dr, index_r; + /* int dr = abs(ir - r); */ + int dr = ((ir > r) ? ir - r : r - ir); + int index_r = (ir << (PNG_QUANTIZE_BLUE_BITS + + PNG_QUANTIZE_GREEN_BITS)); - dr = abs(ir - r); - index_r = (ir << (PNG_DITHER_BLUE_BITS + PNG_DITHER_GREEN_BITS)); for (ig = 0; ig < num_green; ig++) { - int dg, dt, dm, index_g; + /* int dg = abs(ig - g); */ + int dg = ((ig > g) ? ig - g : g - ig); + int dt = dr + dg; + int dm = ((dr > dg) ? dr : dg); + int index_g = index_r | (ig << PNG_QUANTIZE_BLUE_BITS); - dg = abs(ig - g); - dt = dr + dg; - dm = ((dr > dg) ? dr : dg); - index_g = index_r | (ig << PNG_DITHER_BLUE_BITS); for (ib = 0; ib < num_blue; ib++) { - int d_index, db, dmax, d; - - d_index = index_g | ib; - db = abs(ib - b); - dmax = ((dm > db) ? dm : db); - d = dmax + dt + db; + int d_index = index_g | ib; + /* int db = abs(ib - b); */ + int db = ((ib > b) ? ib - b : b - ib); + int dmax = ((dm > db) ? dm : db); + int d = dmax + dt + db; if (d < (int)distance[d_index]) { @@ -544,111 +536,303 @@ png_set_dither(png_structp png_ptr, png_colorp palette, png_free(png_ptr, distance); } } -#endif +#endif /* PNG_READ_QUANTIZE_SUPPORTED */ -#if defined(PNG_READ_GAMMA_SUPPORTED) +#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED) /* Transform the image from the file_gamma to the screen_gamma. We * only do transformations on images where the file_gamma and screen_gamma * are not close reciprocals, otherwise it slows things down slightly, and * also needlessly introduces small errors. + * + * We will turn off gamma transformation later if no semitransparent entries + * are present in the tRNS array for palette images. We can't do it here + * because we don't necessarily have the tRNS chunk yet. */ -void +void PNGAPI png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma) { - png_debug(1, "in png_set_gamma\n"); - if (fabs(scrn_gamma * file_gamma - 1.0) > PNG_GAMMA_THRESHOLD) - png_ptr->transformations |= PNG_GAMMA; + png_debug(1, "in png_set_gamma"); + + if (png_ptr == NULL) + return; + + if ((fabs(scrn_gamma * file_gamma - 1.0) > PNG_GAMMA_THRESHOLD) || + (png_ptr->color_type & PNG_COLOR_MASK_ALPHA) || + (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)) + png_ptr->transformations |= PNG_GAMMA; png_ptr->gamma = (float)file_gamma; png_ptr->screen_gamma = (float)scrn_gamma; } #endif -#if defined(PNG_READ_EXPAND_SUPPORTED) -/* Expand paletted images to rgb, expand grayscale images of - * less then 8 bit depth to 8 bit depth, and expand tRNS chunks +#ifdef PNG_READ_EXPAND_SUPPORTED +/* Expand paletted images to RGB, expand grayscale images of + * less than 8-bit depth to 8-bit depth, and expand tRNS chunks * to alpha channels. */ -void +void PNGAPI png_set_expand(png_structp png_ptr) { - png_debug(1, "in png_set_expand\n"); + png_debug(1, "in png_set_expand"); + + if (png_ptr == NULL) + return; + + png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS); + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} + +/* GRR 19990627: the following three functions currently are identical + * to png_set_expand(). However, it is entirely reasonable that someone + * might wish to expand an indexed image to RGB but *not* expand a single, + * fully transparent palette entry to a full alpha channel--perhaps instead + * convert tRNS to the grayscale/RGB format (16-bit RGB value), or replace + * the transparent color with a particular RGB value, or drop tRNS entirely. + * IOW, a future version of the library may make the transformations flag + * a bit more fine-grained, with separate bits for each of these three + * functions. + * + * More to the point, these functions make it obvious what libpng will be + * doing, whereas "expand" can (and does) mean any number of things. + * + * GRP 20060307: In libpng-1.2.9, png_set_gray_1_2_4_to_8() was modified + * to expand only the sample depth but not to expand the tRNS to alpha + * and its name was changed to png_set_expand_gray_1_2_4_to_8(). + */ + +/* Expand paletted images to RGB. */ +void PNGAPI +png_set_palette_to_rgb(png_structp png_ptr) +{ + png_debug(1, "in png_set_palette_to_rgb"); + + if (png_ptr == NULL) + return; + + png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS); + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} + +/* Expand grayscale images of less than 8-bit depth to 8 bits. */ +void PNGAPI +png_set_expand_gray_1_2_4_to_8(png_structp png_ptr) +{ + png_debug(1, "in png_set_expand_gray_1_2_4_to_8"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_EXPAND; + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; } -#endif -#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) -void + + +/* Expand tRNS chunks to alpha channels. */ +void PNGAPI +png_set_tRNS_to_alpha(png_structp png_ptr) +{ + png_debug(1, "in png_set_tRNS_to_alpha"); + + png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS); + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} +#endif /* defined(PNG_READ_EXPAND_SUPPORTED) */ + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED +void PNGAPI png_set_gray_to_rgb(png_structp png_ptr) { - png_debug(1, "in png_set_gray_to_rgb\n"); + png_debug(1, "in png_set_gray_to_rgb"); + png_ptr->transformations |= PNG_GRAY_TO_RGB; + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; } #endif -#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) -/* Convert a RGB image to a grayscale of the given width. This would - * allow us, for example, to convert a 24 bpp RGB image into an 8 or - * 16 bpp grayscale image. (Not yet implemented.) +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +/* Convert a RGB image to a grayscale of the same width. This allows us, + * for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image. */ -void -png_set_rgb_to_gray(png_structp png_ptr, int gray_bits) + +void PNGAPI +png_set_rgb_to_gray(png_structp png_ptr, int error_action, double red, + double green) +{ + int red_fixed = (int)((float)red*100000.0 + 0.5); + int green_fixed = (int)((float)green*100000.0 + 0.5); + if (png_ptr == NULL) + return; + png_set_rgb_to_gray_fixed(png_ptr, error_action, red_fixed, green_fixed); +} +#endif + +void PNGAPI +png_set_rgb_to_gray_fixed(png_structp png_ptr, int error_action, + png_fixed_point red, png_fixed_point green) { - png_debug(1, "in png_set_rgb_to_gray\n"); - png_ptr->transformations |= PNG_RGB_TO_GRAY; - /* Need to do something with gray_bits here. */ - png_warning(png_ptr, "RGB to GRAY transformation is not yet implemented."); + png_debug(1, "in png_set_rgb_to_gray"); + + if (png_ptr == NULL) + return; + + switch(error_action) + { + case 1: png_ptr->transformations |= PNG_RGB_TO_GRAY; + break; + + case 2: png_ptr->transformations |= PNG_RGB_TO_GRAY_WARN; + break; + + case 3: png_ptr->transformations |= PNG_RGB_TO_GRAY_ERR; + } + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) +#ifdef PNG_READ_EXPAND_SUPPORTED + png_ptr->transformations |= PNG_EXPAND; +#else + { + png_warning(png_ptr, + "Cannot do RGB_TO_GRAY without EXPAND_SUPPORTED"); + png_ptr->transformations &= ~PNG_RGB_TO_GRAY; + } +#endif + { + png_uint_16 red_int, green_int; + if (red < 0 || green < 0) + { + red_int = 6968; /* .212671 * 32768 + .5 */ + green_int = 23434; /* .715160 * 32768 + .5 */ + } + else if (red + green < 100000L) + { + red_int = (png_uint_16)(((png_uint_32)red*32768L)/100000L); + green_int = (png_uint_16)(((png_uint_32)green*32768L)/100000L); + } + else + { + png_warning(png_ptr, "ignoring out of range rgb_to_gray coefficients"); + red_int = 6968; + green_int = 23434; + } + png_ptr->rgb_to_gray_red_coeff = red_int; + png_ptr->rgb_to_gray_green_coeff = green_int; + png_ptr->rgb_to_gray_blue_coeff = + (png_uint_16)(32768 - red_int - green_int); + } } #endif -#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) -void +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ + defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) +void PNGAPI png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr read_user_transform_fn) { - png_debug(1, "in png_set_read_user_transform_fn\n"); + png_debug(1, "in png_set_read_user_transform_fn"); + + if (png_ptr == NULL) + return; + +#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED png_ptr->transformations |= PNG_USER_TRANSFORM; png_ptr->read_user_transform_fn = read_user_transform_fn; +#endif } #endif /* Initialize everything needed for the read. This includes modifying * the palette. */ -void +void /* PRIVATE */ png_init_read_transformations(png_structp png_ptr) { - int color_type; + png_debug(1, "in png_init_read_transformations"); - png_debug(1, "in png_init_read_transformations\n"); - color_type = png_ptr->color_type; + { +#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ + defined(PNG_READ_SHIFT_SUPPORTED) || \ + defined(PNG_READ_GAMMA_SUPPORTED) + int color_type = png_ptr->color_type; +#endif #if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED) - if (png_ptr->transformations & PNG_BACKGROUND_EXPAND) + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* Detect gray background and attempt to enable optimization + * for gray --> RGB case + * + * Note: if PNG_BACKGROUND_EXPAND is set and color_type is either RGB or + * RGB_ALPHA (in which case need_expand is superfluous anyway), the + * background color might actually be gray yet not be flagged as such. + * This is not a problem for the current code, which uses + * PNG_BACKGROUND_IS_GRAY only to decide when to do the + * png_do_gray_to_rgb() transformation. + */ + if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) && + !(color_type & PNG_COLOR_MASK_COLOR)) + { + png_ptr->mode |= PNG_BACKGROUND_IS_GRAY; + } else if ((png_ptr->transformations & PNG_BACKGROUND) && + !(png_ptr->transformations & PNG_BACKGROUND_EXPAND) && + (png_ptr->transformations & PNG_GRAY_TO_RGB) && + png_ptr->background.red == png_ptr->background.green && + png_ptr->background.red == png_ptr->background.blue) + { + png_ptr->mode |= PNG_BACKGROUND_IS_GRAY; + png_ptr->background.gray = png_ptr->background.red; + } +#endif + + if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) && + (png_ptr->transformations & PNG_EXPAND)) { - if (color_type == PNG_COLOR_TYPE_GRAY) + if (!(color_type & PNG_COLOR_MASK_COLOR)) /* i.e., GRAY or GRAY_ALPHA */ { - /* expand background chunk. */ + /* Expand background and tRNS chunks */ switch (png_ptr->bit_depth) { case 1: png_ptr->background.gray *= (png_uint_16)0xff; - png_ptr->background.red = png_ptr->background.green = - png_ptr->background.blue = png_ptr->background.gray; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) + { + png_ptr->trans_color.gray *= (png_uint_16)0xff; + png_ptr->trans_color.red = png_ptr->trans_color.green + = png_ptr->trans_color.blue = png_ptr->trans_color.gray; + } break; + case 2: png_ptr->background.gray *= (png_uint_16)0x55; - png_ptr->background.red = png_ptr->background.green = - png_ptr->background.blue = png_ptr->background.gray; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) + { + png_ptr->trans_color.gray *= (png_uint_16)0x55; + png_ptr->trans_color.red = png_ptr->trans_color.green + = png_ptr->trans_color.blue = png_ptr->trans_color.gray; + } break; + case 4: png_ptr->background.gray *= (png_uint_16)0x11; - png_ptr->background.red = png_ptr->background.green = - png_ptr->background.blue = png_ptr->background.gray; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) + { + png_ptr->trans_color.gray *= (png_uint_16)0x11; + png_ptr->trans_color.red = png_ptr->trans_color.green + = png_ptr->trans_color.blue = png_ptr->trans_color.gray; + } break; + case 8: + case 16: - png_ptr->background.red = png_ptr->background.green = - png_ptr->background.blue = png_ptr->background.gray; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; break; } } @@ -661,18 +845,20 @@ png_init_read_transformations(png_structp png_ptr) png_ptr->background.blue = png_ptr->palette[png_ptr->background.index].blue; -#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED if (png_ptr->transformations & PNG_INVERT_ALPHA) { -#if defined(PNG_READ_EXPAND_SUPPORTED) - if (!(png_ptr->transformations & PNG_EXPAND)) +#ifdef PNG_READ_EXPAND_SUPPORTED + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) #endif { - /* invert the alpha channel (in tRNS) unless the pixels are - going to be expanded, in which case leave it for later */ - int i; - for (i=0; i<(int)png_ptr->num_trans; i++) - png_ptr->trans[i] = 255 - png_ptr->trans[i]; + /* Invert the alpha channel (in tRNS) unless the pixels are + * going to be expanded, in which case leave it for later + */ + int i, istop; + istop=(int)png_ptr->num_trans; + for (i=0; itrans_alpha[i] = (png_byte)(255 - png_ptr->trans_alpha[i]); } } #endif @@ -681,25 +867,41 @@ png_init_read_transformations(png_structp png_ptr) } #endif -#if defined(PNG_READ_BACKGROUND_SUPPORTED) +#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED) png_ptr->background_1 = png_ptr->background; #endif -#if defined(PNG_READ_GAMMA_SUPPORTED) - if (png_ptr->transformations & PNG_GAMMA) +#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED) + + if ((color_type == PNG_COLOR_TYPE_PALETTE && png_ptr->num_trans != 0) + && (fabs(png_ptr->screen_gamma * png_ptr->gamma - 1.0) + < PNG_GAMMA_THRESHOLD)) + { + int i, k; + k=0; + for (i=0; inum_trans; i++) + { + if (png_ptr->trans_alpha[i] != 0 && png_ptr->trans_alpha[i] != 0xff) + k=1; /* Partial transparency is present */ + } + if (k == 0) + png_ptr->transformations &= ~PNG_GAMMA; + } + + if ((png_ptr->transformations & (PNG_GAMMA | PNG_RGB_TO_GRAY)) && + png_ptr->gamma != 0.0) { - png_build_gamma_table(png_ptr); -#if defined(PNG_READ_BACKGROUND_SUPPORTED) + png_build_gamma_table(png_ptr, png_ptr->bit_depth); + +#ifdef PNG_READ_BACKGROUND_SUPPORTED if (png_ptr->transformations & PNG_BACKGROUND) { if (color_type == PNG_COLOR_TYPE_PALETTE) { - int num_palette, i; + /* Could skip if no transparency */ png_color back, back_1; - png_colorp palette; - - palette = png_ptr->palette; - num_palette = png_ptr->num_palette; - + png_colorp palette = png_ptr->palette; + int num_palette = png_ptr->num_palette; + int i; if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE) { back.red = png_ptr->gamma_table[png_ptr->background.red]; @@ -720,10 +922,12 @@ png_init_read_transformations(png_structp png_ptr) g = (png_ptr->screen_gamma); gs = 1.0; break; + case PNG_BACKGROUND_GAMMA_FILE: g = 1.0 / (png_ptr->gamma); gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); break; + case PNG_BACKGROUND_GAMMA_UNIQUE: g = 1.0 / (png_ptr->background_gamma); gs = 1.0 / (png_ptr->background_gamma * @@ -743,43 +947,43 @@ png_init_read_transformations(png_structp png_ptr) else { back.red = (png_byte)(pow( - (double)png_ptr->background.red/255, gs) * 255.0 + .5); + (double)png_ptr->background.red/255.0, gs) * 255.0 + .5); back.green = (png_byte)(pow( - (double)png_ptr->background.green/255, gs) * 255.0 + .5); + (double)png_ptr->background.green/255.0, gs) * 255.0 + + .5); back.blue = (png_byte)(pow( - (double)png_ptr->background.blue/255, gs) * 255.0 + .5); + (double)png_ptr->background.blue/255.0, gs) * 255.0 + .5); } back_1.red = (png_byte)(pow( - (double)png_ptr->background.red/255, g) * 255.0 + .5); + (double)png_ptr->background.red/255.0, g) * 255.0 + .5); back_1.green = (png_byte)(pow( - (double)png_ptr->background.green/255, g) * 255.0 + .5); + (double)png_ptr->background.green/255.0, g) * 255.0 + .5); back_1.blue = (png_byte)(pow( - (double)png_ptr->background.blue/255, g) * 255.0 + .5); + (double)png_ptr->background.blue/255.0, g) * 255.0 + .5); } - for (i = 0; i < num_palette; i++) { - if (i < (int)png_ptr->num_trans && png_ptr->trans[i] != 0xff) + if (i < (int)png_ptr->num_trans && png_ptr->trans_alpha[i] != 0xff) { - if (png_ptr->trans[i] == 0) + if (png_ptr->trans_alpha[i] == 0) { palette[i] = back; } - else /* if (png_ptr->trans[i] != 0xff) */ + else /* if (png_ptr->trans_alpha[i] != 0xff) */ { png_byte v, w; v = png_ptr->gamma_to_1[palette[i].red]; - png_composite(w, v, png_ptr->trans[i], back_1.red); + png_composite(w, v, png_ptr->trans_alpha[i], back_1.red); palette[i].red = png_ptr->gamma_from_1[w]; v = png_ptr->gamma_to_1[palette[i].green]; - png_composite(w, v, png_ptr->trans[i], back_1.green); + png_composite(w, v, png_ptr->trans_alpha[i], back_1.green); palette[i].green = png_ptr->gamma_from_1[w]; v = png_ptr->gamma_to_1[palette[i].blue]; - png_composite(w, v, png_ptr->trans[i], back_1.blue); + png_composite(w, v, png_ptr->trans_alpha[i], back_1.blue); palette[i].blue = png_ptr->gamma_from_1[w]; } } @@ -790,16 +994,22 @@ png_init_read_transformations(png_structp png_ptr) palette[i].blue = png_ptr->gamma_table[palette[i].blue]; } } + /* Prevent the transformations being done again, and make sure + * that the now spurious alpha channel is stripped - the code + * has just reduced background composition and gamma correction + * to a simple alpha channel strip. + */ + png_ptr->transformations &= ~PNG_BACKGROUND; + png_ptr->transformations &= ~PNG_GAMMA; + png_ptr->transformations |= PNG_STRIP_ALPHA; } - /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN)*/ + /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN) */ else /* color_type != PNG_COLOR_TYPE_PALETTE */ { - double g, gs, m; - - m = (double)(((png_uint_32)1 << png_ptr->bit_depth) - 1); - g = 1.0; - gs = 1.0; + double m = (double)(((png_uint_32)1 << png_ptr->bit_depth) - 1); + double g = 1.0; + double gs = 1.0; switch (png_ptr->background_gamma_type) { @@ -807,10 +1017,12 @@ png_init_read_transformations(png_structp png_ptr) g = (png_ptr->screen_gamma); gs = 1.0; break; + case PNG_BACKGROUND_GAMMA_FILE: g = 1.0 / (png_ptr->gamma); gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); break; + case PNG_BACKGROUND_GAMMA_UNIQUE: g = 1.0 / (png_ptr->background_gamma); gs = 1.0 / (png_ptr->background_gamma * @@ -818,9 +1030,16 @@ png_init_read_transformations(png_structp png_ptr) break; } - if (color_type & PNG_COLOR_MASK_COLOR) + png_ptr->background_1.gray = (png_uint_16)(pow( + (double)png_ptr->background.gray / m, g) * m + .5); + png_ptr->background.gray = (png_uint_16)(pow( + (double)png_ptr->background.gray / m, gs) * m + .5); + + if ((png_ptr->background.red != png_ptr->background.green) || + (png_ptr->background.red != png_ptr->background.blue) || + (png_ptr->background.red != png_ptr->background.gray)) { - /* RGB or RGBA */ + /* RGB or RGBA with color background */ png_ptr->background_1.red = (png_uint_16)(pow( (double)png_ptr->background.red / m, g) * m + .5); png_ptr->background_1.green = (png_uint_16)(pow( @@ -836,24 +1055,22 @@ png_init_read_transformations(png_structp png_ptr) } else { - /* GRAY or GRAY ALPHA */ - png_ptr->background_1.gray = (png_uint_16)(pow( - (double)png_ptr->background.gray / m, g) * m + .5); - png_ptr->background.gray = (png_uint_16)(pow( - (double)png_ptr->background.gray / m, gs) * m + .5); + /* GRAY, GRAY ALPHA, RGB, or RGBA with gray background */ + png_ptr->background_1.red = png_ptr->background_1.green + = png_ptr->background_1.blue = png_ptr->background_1.gray; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; } } } else - /* transformation does not include PNG_BACKGROUND */ -#endif + /* Transformation does not include PNG_BACKGROUND */ +#endif /* PNG_READ_BACKGROUND_SUPPORTED */ if (color_type == PNG_COLOR_TYPE_PALETTE) { - int num_palette, i; - png_colorp palette; - - palette = png_ptr->palette; - num_palette = png_ptr->num_palette; + png_colorp palette = png_ptr->palette; + int num_palette = png_ptr->num_palette; + int i; for (i = 0; i < num_palette; i++) { @@ -861,68 +1078,82 @@ png_init_read_transformations(png_structp png_ptr) palette[i].green = png_ptr->gamma_table[palette[i].green]; palette[i].blue = png_ptr->gamma_table[palette[i].blue]; } + + /* Done the gamma correction. */ + png_ptr->transformations &= ~PNG_GAMMA; } } -#if defined(PNG_READ_BACKGROUND_SUPPORTED) +#ifdef PNG_READ_BACKGROUND_SUPPORTED else #endif -#endif -#if defined(PNG_READ_BACKGROUND_SUPPORTED) +#endif /* PNG_READ_GAMMA_SUPPORTED && PNG_FLOATING_POINT_SUPPORTED */ +#ifdef PNG_READ_BACKGROUND_SUPPORTED /* No GAMMA transformation */ - if (png_ptr->transformations & PNG_BACKGROUND && - color_type == PNG_COLOR_TYPE_PALETTE) + if ((png_ptr->transformations & PNG_BACKGROUND) && + (color_type == PNG_COLOR_TYPE_PALETTE)) { int i; + int istop = (int)png_ptr->num_trans; png_color back; - png_colorp palette; + png_colorp palette = png_ptr->palette; - palette = png_ptr->palette; back.red = (png_byte)png_ptr->background.red; back.green = (png_byte)png_ptr->background.green; back.blue = (png_byte)png_ptr->background.blue; - for (i = 0; i < (int)png_ptr->num_trans; i++) + for (i = 0; i < istop; i++) { - if (png_ptr->trans[i] == 0) + if (png_ptr->trans_alpha[i] == 0) { palette[i] = back; } - else if (png_ptr->trans[i] != 0xff) + else if (png_ptr->trans_alpha[i] != 0xff) { + /* The png_composite() macro is defined in png.h */ png_composite(palette[i].red, palette[i].red, - png_ptr->trans[i], back.red); + png_ptr->trans_alpha[i], back.red); png_composite(palette[i].green, palette[i].green, - png_ptr->trans[i], back.green); + png_ptr->trans_alpha[i], back.green); png_composite(palette[i].blue, palette[i].blue, - png_ptr->trans[i], back.blue); + png_ptr->trans_alpha[i], back.blue); } } + + /* Handled alpha, still need to strip the channel. */ + png_ptr->transformations &= ~PNG_BACKGROUND; + png_ptr->transformations |= PNG_STRIP_ALPHA; } -#endif +#endif /* PNG_READ_BACKGROUND_SUPPORTED */ -#if defined(PNG_READ_SHIFT_SUPPORTED) +#ifdef PNG_READ_SHIFT_SUPPORTED if ((png_ptr->transformations & PNG_SHIFT) && - color_type == PNG_COLOR_TYPE_PALETTE) + (color_type == PNG_COLOR_TYPE_PALETTE)) { png_uint_16 i; - int sr, sg, sb; + png_uint_16 istop = png_ptr->num_palette; + int sr = 8 - png_ptr->sig_bit.red; + int sg = 8 - png_ptr->sig_bit.green; + int sb = 8 - png_ptr->sig_bit.blue; - sr = 8 - png_ptr->sig_bit.red; if (sr < 0 || sr > 8) sr = 0; - sg = 8 - png_ptr->sig_bit.green; if (sg < 0 || sg > 8) sg = 0; - sb = 8 - png_ptr->sig_bit.blue; if (sb < 0 || sb > 8) sb = 0; - for (i = 0; i < png_ptr->num_palette; i++) + for (i = 0; i < istop; i++) { png_ptr->palette[i].red >>= sr; png_ptr->palette[i].green >>= sg; png_ptr->palette[i].blue >>= sb; } } +#endif /* PNG_READ_SHIFT_SUPPORTED */ + } +#if !defined(PNG_READ_GAMMA_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) \ + && !defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr) + return; #endif } @@ -930,16 +1161,18 @@ png_init_read_transformations(png_structp png_ptr) * info should be updated so a PNG file could be written with it, * assuming the transformations result in valid PNG data. */ -void +void /* PRIVATE */ png_read_transform_info(png_structp png_ptr, png_infop info_ptr) { - png_debug(1, "in png_read_transform_info\n"); -#if defined(PNG_READ_EXPAND_SUPPORTED) + png_debug(1, "in png_read_transform_info"); + +#ifdef PNG_READ_EXPAND_SUPPORTED if (png_ptr->transformations & PNG_EXPAND) { if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) { - if (png_ptr->num_trans) + if (png_ptr->num_trans && + (png_ptr->transformations & PNG_EXPAND_tRNS)) info_ptr->color_type = PNG_COLOR_TYPE_RGB_ALPHA; else info_ptr->color_type = PNG_COLOR_TYPE_RGB; @@ -949,7 +1182,10 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr) else { if (png_ptr->num_trans) - info_ptr->color_type |= PNG_COLOR_MASK_ALPHA; + { + if (png_ptr->transformations & PNG_EXPAND_tRNS) + info_ptr->color_type |= PNG_COLOR_MASK_ALPHA; + } if (info_ptr->bit_depth < 8) info_ptr->bit_depth = 8; info_ptr->num_trans = 0; @@ -957,7 +1193,7 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr) } #endif -#if defined(PNG_READ_BACKGROUND_SUPPORTED) +#ifdef PNG_READ_BACKGROUND_SUPPORTED if (png_ptr->transformations & PNG_BACKGROUND) { info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA; @@ -966,33 +1202,50 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr) } #endif -#if defined(PNG_READ_16_TO_8_SUPPORTED) - if ((png_ptr->transformations & PNG_16_TO_8) && info_ptr->bit_depth == 16) +#ifdef PNG_READ_GAMMA_SUPPORTED + if (png_ptr->transformations & PNG_GAMMA) + { +#ifdef PNG_FLOATING_POINT_SUPPORTED + info_ptr->gamma = png_ptr->gamma; +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED + info_ptr->int_gamma = png_ptr->int_gamma; +#endif + } +#endif + +#ifdef PNG_READ_16_TO_8_SUPPORTED + if ((png_ptr->transformations & PNG_16_TO_8) && (info_ptr->bit_depth == 16)) info_ptr->bit_depth = 8; #endif -#if defined(PNG_READ_DITHER_SUPPORTED) - if (png_ptr->transformations & PNG_DITHER) +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + if (png_ptr->transformations & PNG_GRAY_TO_RGB) + info_ptr->color_type |= PNG_COLOR_MASK_COLOR; +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED + if (png_ptr->transformations & PNG_RGB_TO_GRAY) + info_ptr->color_type &= ~PNG_COLOR_MASK_COLOR; +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED + if (png_ptr->transformations & PNG_QUANTIZE) { if (((info_ptr->color_type == PNG_COLOR_TYPE_RGB) || - (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) && - png_ptr->palette_lookup && info_ptr->bit_depth == 8) + (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) && + png_ptr->palette_lookup && info_ptr->bit_depth == 8) { info_ptr->color_type = PNG_COLOR_TYPE_PALETTE; } } #endif -#if defined(PNG_READ_PACK_SUPPORTED) - if ((png_ptr->transformations & PNG_PACK) && info_ptr->bit_depth < 8) +#ifdef PNG_READ_PACK_SUPPORTED + if ((png_ptr->transformations & PNG_PACK) && (info_ptr->bit_depth < 8)) info_ptr->bit_depth = 8; #endif -#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) - if (png_ptr->transformations & PNG_GRAY_TO_RGB) - info_ptr->color_type |= PNG_COLOR_MASK_COLOR; -#endif - if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) info_ptr->channels = 1; else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR) @@ -1000,64 +1253,98 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr) else info_ptr->channels = 1; -#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) - if (png_ptr->transformations & PNG_STRIP_ALPHA) +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED + if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA) info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA; #endif -#if defined(PNG_READ_FILLER_SUPPORTED) + if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA) + info_ptr->channels++; + +#ifdef PNG_READ_FILLER_SUPPORTED + /* STRIP_ALPHA and FILLER allowed: MASK_ALPHA bit stripped above */ if ((png_ptr->transformations & PNG_FILLER) && - info_ptr->color_type & PNG_COLOR_TYPE_RGB && - info_ptr->channels == 3) + ((info_ptr->color_type == PNG_COLOR_TYPE_RGB) || + (info_ptr->color_type == PNG_COLOR_TYPE_GRAY))) { - info_ptr->channels = 4; + info_ptr->channels++; + /* If adding a true alpha channel not just filler */ + if (png_ptr->transformations & PNG_ADD_ALPHA) + info_ptr->color_type |= PNG_COLOR_MASK_ALPHA; } #endif - if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA) - info_ptr->channels++; +#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) && \ +defined(PNG_READ_USER_TRANSFORM_SUPPORTED) + if (png_ptr->transformations & PNG_USER_TRANSFORM) + { + if (info_ptr->bit_depth < png_ptr->user_transform_depth) + info_ptr->bit_depth = png_ptr->user_transform_depth; + if (info_ptr->channels < png_ptr->user_transform_channels) + info_ptr->channels = png_ptr->user_transform_channels; + } +#endif + info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth); - info_ptr->rowbytes = ((info_ptr->width * info_ptr->pixel_depth + 7) >> 3); + info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, info_ptr->width); + +#ifndef PNG_READ_EXPAND_SUPPORTED + if (png_ptr) + return; +#endif } /* Transform the row. The order of transformations is significant, * and is very touchy. If you add a transformation, take care to * decide how it fits in with the other transformations here. */ -void +void /* PRIVATE */ png_do_read_transformations(png_structp png_ptr) { - png_debug(1, "in png_do_read_transformations\n"); -#if !defined(PNG_USELESS_TESTS_SUPPORTED) + png_debug(1, "in png_do_read_transformations"); + if (png_ptr->row_buf == NULL) { -#if !defined(PNG_NO_STDIO) +#ifdef PNG_STDIO_SUPPORTED char msg[50]; - sprintf(msg, "NULL row buffer for row %ld, pass %d", png_ptr->row_number, + png_snprintf2(msg, 50, + "NULL row buffer for row %ld, pass %d", (long)png_ptr->row_number, png_ptr->pass); png_error(png_ptr, msg); #else png_error(png_ptr, "NULL row buffer"); #endif } +#ifdef PNG_WARN_UNINITIALIZED_ROW + if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) + /* Application has failed to call either png_read_start_image() + * or png_read_update_info() after setting transforms that expand + * pixels. This check added to libpng-1.2.19 + */ +#if (PNG_WARN_UNINITIALIZED_ROW==1) + png_error(png_ptr, "Uninitialized row"); +#else + png_warning(png_ptr, "Uninitialized row"); +#endif #endif -#if defined(PNG_READ_EXPAND_SUPPORTED) +#ifdef PNG_READ_EXPAND_SUPPORTED if (png_ptr->transformations & PNG_EXPAND) { if (png_ptr->row_info.color_type == PNG_COLOR_TYPE_PALETTE) { png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1, - png_ptr->palette, png_ptr->trans, png_ptr->num_trans); + png_ptr->palette, png_ptr->trans_alpha, png_ptr->num_trans); } - else if (png_ptr->transformations & PNG_EXPAND) + else { - if (png_ptr->num_trans) + if (png_ptr->num_trans && + (png_ptr->transformations & PNG_EXPAND_tRNS)) png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1, - &(png_ptr->trans_values)); + &(png_ptr->trans_color)); else png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1, NULL); @@ -1065,153 +1352,225 @@ png_do_read_transformations(png_structp png_ptr) } #endif -#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) - if (png_ptr->transformations & PNG_STRIP_ALPHA) +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED + if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA) png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, - PNG_FLAG_FILLER_AFTER); + PNG_FLAG_FILLER_AFTER | (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)); +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED + if (png_ptr->transformations & PNG_RGB_TO_GRAY) + { + int rgb_error = + png_do_rgb_to_gray(png_ptr, &(png_ptr->row_info), + png_ptr->row_buf + 1); + if (rgb_error) + { + png_ptr->rgb_to_gray_status=1; + if ((png_ptr->transformations & PNG_RGB_TO_GRAY) == + PNG_RGB_TO_GRAY_WARN) + png_warning(png_ptr, "png_do_rgb_to_gray found nongray pixel"); + if ((png_ptr->transformations & PNG_RGB_TO_GRAY) == + PNG_RGB_TO_GRAY_ERR) + png_error(png_ptr, "png_do_rgb_to_gray found nongray pixel"); + } + } +#endif + +/* From Andreas Dilger e-mail to png-implement, 26 March 1998: + * + * In most cases, the "simple transparency" should be done prior to doing + * gray-to-RGB, or you will have to test 3x as many bytes to check if a + * pixel is transparent. You would also need to make sure that the + * transparency information is upgraded to RGB. + * + * To summarize, the current flow is: + * - Gray + simple transparency -> compare 1 or 2 gray bytes and composite + * with background "in place" if transparent, + * convert to RGB if necessary + * - Gray + alpha -> composite with gray background and remove alpha bytes, + * convert to RGB if necessary + * + * To support RGB backgrounds for gray images we need: + * - Gray + simple transparency -> convert to RGB + simple transparency, + * compare 3 or 6 bytes and composite with + * background "in place" if transparent + * (3x compare/pixel compared to doing + * composite with gray bkgrnd) + * - Gray + alpha -> convert to RGB + alpha, composite with background and + * remove alpha bytes (3x float + * operations/pixel compared with composite + * on gray background) + * + * Greg's change will do this. The reason it wasn't done before is for + * performance, as this increases the per-pixel operations. If we would check + * in advance if the background was gray or RGB, and position the gray-to-RGB + * transform appropriately, then it would save a lot of work/time. + */ + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* If gray -> RGB, do so now only if background is non-gray; else do later + * for performance reasons + */ + if ((png_ptr->transformations & PNG_GRAY_TO_RGB) && + !(png_ptr->mode & PNG_BACKGROUND_IS_GRAY)) + png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_BACKGROUND_SUPPORTED) +#ifdef PNG_READ_BACKGROUND_SUPPORTED if ((png_ptr->transformations & PNG_BACKGROUND) && ((png_ptr->num_trans != 0 ) || (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) png_do_background(&(png_ptr->row_info), png_ptr->row_buf + 1, - &(png_ptr->trans_values), &(png_ptr->background), - &(png_ptr->background_1), + &(png_ptr->trans_color), &(png_ptr->background) +#ifdef PNG_READ_GAMMA_SUPPORTED + , &(png_ptr->background_1), png_ptr->gamma_table, png_ptr->gamma_from_1, png_ptr->gamma_to_1, png_ptr->gamma_16_table, png_ptr->gamma_16_from_1, png_ptr->gamma_16_to_1, - png_ptr->gamma_shift); + png_ptr->gamma_shift +#endif +); #endif -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if ((png_ptr->transformations & PNG_GAMMA) && - !(png_ptr->transformations & PNG_BACKGROUND) && - (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)) - png_do_gamma(&(png_ptr->row_info), png_ptr->row_buf + 1, - png_ptr->gamma_table, png_ptr->gamma_16_table, - png_ptr->gamma_shift); +#ifdef PNG_READ_BACKGROUND_SUPPORTED + !((png_ptr->transformations & PNG_BACKGROUND) && + ((png_ptr->num_trans != 0) || + (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) && #endif - -#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) - if (png_ptr->transformations & PNG_RGB_TO_GRAY) - png_do_rgb_to_gray(&(png_ptr->row_info), png_ptr->row_buf + 1); + (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)) + png_do_gamma(&(png_ptr->row_info), png_ptr->row_buf + 1, + png_ptr->gamma_table, png_ptr->gamma_16_table, + png_ptr->gamma_shift); #endif -#if defined(PNG_READ_16_TO_8_SUPPORTED) +#ifdef PNG_READ_16_TO_8_SUPPORTED if (png_ptr->transformations & PNG_16_TO_8) png_do_chop(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_DITHER_SUPPORTED) - if (png_ptr->transformations & PNG_DITHER) +#ifdef PNG_READ_QUANTIZE_SUPPORTED + if (png_ptr->transformations & PNG_QUANTIZE) { - png_do_dither((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1, - png_ptr->palette_lookup, png_ptr->dither_index); - if(png_ptr->row_info.rowbytes == (png_uint_32)0) - png_error(png_ptr, "png_do_dither returned rowbytes=0"); + png_do_quantize((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1, + png_ptr->palette_lookup, png_ptr->quantize_index); + if (png_ptr->row_info.rowbytes == (png_uint_32)0) + png_error(png_ptr, "png_do_quantize returned rowbytes=0"); } #endif -#if defined(PNG_READ_INVERT_SUPPORTED) +#ifdef PNG_READ_INVERT_SUPPORTED if (png_ptr->transformations & PNG_INVERT_MONO) png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_SHIFT_SUPPORTED) +#ifdef PNG_READ_SHIFT_SUPPORTED if (png_ptr->transformations & PNG_SHIFT) png_do_unshift(&(png_ptr->row_info), png_ptr->row_buf + 1, &(png_ptr->shift)); #endif -#if defined(PNG_READ_PACK_SUPPORTED) +#ifdef PNG_READ_PACK_SUPPORTED if (png_ptr->transformations & PNG_PACK) png_do_unpack(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_BGR_SUPPORTED) +#ifdef PNG_READ_BGR_SUPPORTED if (png_ptr->transformations & PNG_BGR) png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_PACKSWAP_SUPPORTED) +#ifdef PNG_READ_PACKSWAP_SUPPORTED if (png_ptr->transformations & PNG_PACKSWAP) png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) - if (png_ptr->transformations & PNG_GRAY_TO_RGB) +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* If gray -> RGB, do so now only if we did not do so above */ + if ((png_ptr->transformations & PNG_GRAY_TO_RGB) && + (png_ptr->mode & PNG_BACKGROUND_IS_GRAY)) png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_FILLER_SUPPORTED) +#ifdef PNG_READ_FILLER_SUPPORTED if (png_ptr->transformations & PNG_FILLER) png_do_read_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, (png_uint_32)png_ptr->filler, png_ptr->flags); #endif -#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED if (png_ptr->transformations & PNG_INVERT_ALPHA) png_do_read_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED if (png_ptr->transformations & PNG_SWAP_ALPHA) png_do_read_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_SWAP_SUPPORTED) +#ifdef PNG_READ_SWAP_SUPPORTED if (png_ptr->transformations & PNG_SWAP_BYTES) png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif -#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) +#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED if (png_ptr->transformations & PNG_USER_TRANSFORM) - if(png_ptr->read_user_transform_fn != NULL) - (*(png_ptr->read_user_transform_fn)) /* user read transform function */ - (png_ptr, /* png_ptr */ - &(png_ptr->row_info), /* row_info: */ - /* png_uint_32 width; width of row */ - /* png_uint_32 rowbytes; number of bytes in row */ - /* png_byte color_type; color type of pixels */ - /* png_byte bit_depth; bit depth of samples */ - /* png_byte channels; number of channels (1-4) */ - /* png_byte pixel_depth; bits per pixel (depth*channels) */ - png_ptr->row_buf + 1); /* start of pixel data for row */ + { + if (png_ptr->read_user_transform_fn != NULL) + (*(png_ptr->read_user_transform_fn)) /* User read transform function */ + (png_ptr, /* png_ptr */ + &(png_ptr->row_info), /* row_info: */ + /* png_uint_32 width; width of row */ + /* png_uint_32 rowbytes; number of bytes in row */ + /* png_byte color_type; color type of pixels */ + /* png_byte bit_depth; bit depth of samples */ + /* png_byte channels; number of channels (1-4) */ + /* png_byte pixel_depth; bits per pixel (depth*channels) */ + png_ptr->row_buf + 1); /* start of pixel data for row */ +#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED + if (png_ptr->user_transform_depth) + png_ptr->row_info.bit_depth = png_ptr->user_transform_depth; + if (png_ptr->user_transform_channels) + png_ptr->row_info.channels = png_ptr->user_transform_channels; +#endif + png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth * + png_ptr->row_info.channels); + png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, + png_ptr->row_info.width); + } #endif } -#if defined(PNG_READ_PACK_SUPPORTED) +#ifdef PNG_READ_PACK_SUPPORTED /* Unpack pixels of 1, 2, or 4 bits per pixel into 1 byte per pixel, * without changing the actual values. Thus, if you had a row with * a bit depth of 1, you would end up with bytes that only contained * the numbers 0 or 1. If you would rather they contain 0 and 255, use * png_do_shift() after this. */ -void +void /* PRIVATE */ png_do_unpack(png_row_infop row_info, png_bytep row) { - png_debug(1, "in png_do_unpack\n"); -#if defined(PNG_USELESS_TESTS_SUPPORTED) - if (row != NULL && row_info != NULL && row_info->bit_depth < 8) -#else + png_debug(1, "in png_do_unpack"); + if (row_info->bit_depth < 8) -#endif { - png_uint_32 shift, i; - png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width=row_info->width; switch (row_info->bit_depth) { case 1: { - sp = row + (png_size_t)((row_info->width - 1) >> 3); - dp = row + (png_size_t)row_info->width - 1; - shift = 7 - (int)((row_info->width + 7) & 7); - for (i = 0; i < row_info->width; i++) + png_bytep sp = row + (png_size_t)((row_width - 1) >> 3); + png_bytep dp = row + (png_size_t)row_width - 1; + png_uint_32 shift = 7 - (int)((row_width + 7) & 0x07); + for (i = 0; i < row_width; i++) { - *dp = (png_byte)((*sp >> shift) & 0x1); + *dp = (png_byte)((*sp >> shift) & 0x01); if (shift == 7) { shift = 0; @@ -1224,15 +1583,16 @@ png_do_unpack(png_row_infop row_info, png_bytep row) } break; } + case 2: { - sp = row + (png_size_t)((row_info->width - 1) >> 2); - dp = row + (png_size_t)row_info->width - 1; - shift = (int)((3 - ((row_info->width + 3) & 3)) << 1); - for (i = 0; i < row_info->width; i++) + png_bytep sp = row + (png_size_t)((row_width - 1) >> 2); + png_bytep dp = row + (png_size_t)row_width - 1; + png_uint_32 shift = (int)((3 - ((row_width + 3) & 0x03)) << 1); + for (i = 0; i < row_width; i++) { - *dp = (png_byte)((*sp >> shift) & 0x3); + *dp = (png_byte)((*sp >> shift) & 0x03); if (shift == 6) { shift = 0; @@ -1245,14 +1605,15 @@ png_do_unpack(png_row_infop row_info, png_bytep row) } break; } + case 4: { - sp = row + (png_size_t)((row_info->width - 1) >> 1); - dp = row + (png_size_t)row_info->width - 1; - shift = (int)((1 - ((row_info->width + 1) & 1)) << 2); - for (i = 0; i < row_info->width; i++) + png_bytep sp = row + (png_size_t)((row_width - 1) >> 1); + png_bytep dp = row + (png_size_t)row_width - 1; + png_uint_32 shift = (int)((1 - ((row_width + 1) & 0x01)) << 2); + for (i = 0; i < row_width; i++) { - *dp = (png_byte)((*sp >> shift) & 0xf); + *dp = (png_byte)((*sp >> shift) & 0x0f); if (shift == 4) { shift = 0; @@ -1268,32 +1629,31 @@ png_do_unpack(png_row_infop row_info, png_bytep row) } row_info->bit_depth = 8; row_info->pixel_depth = (png_byte)(8 * row_info->channels); - row_info->rowbytes = row_info->width * row_info->channels; + row_info->rowbytes = row_width * row_info->channels; } } #endif -#if defined(PNG_READ_SHIFT_SUPPORTED) +#ifdef PNG_READ_SHIFT_SUPPORTED /* Reverse the effects of png_do_shift. This routine merely shifts the * pixels back to their significant bits values. Thus, if you have * a row of bit depth 8, but only 5 are significant, this will shift * the values back to 0 through 31. */ -void +void /* PRIVATE */ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits) { - png_debug(1, "in png_do_unshift\n"); + png_debug(1, "in png_do_unshift"); + if ( -#if defined(PNG_USELESS_TESTS_SUPPORTED) - row != NULL && row_info != NULL && sig_bits != NULL && -#endif row_info->color_type != PNG_COLOR_TYPE_PALETTE) { int shift[4]; - int channels, c; - png_uint_16 value; + int channels = 0; + int c; + png_uint_16 value = 0; + png_uint_32 row_width = row_info->width; - channels = 0; if (row_info->color_type & PNG_COLOR_MASK_COLOR) { shift[channels++] = row_info->bit_depth - sig_bits->red; @@ -1309,8 +1669,6 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits) shift[channels++] = row_info->bit_depth - sig_bits->alpha; } - value = 0; - for (c = 0; c < channels; c++) { if (shift[c] <= 0) @@ -1328,57 +1686,57 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits) { png_bytep bp; png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; - for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++) + for (bp = row, i = 0; i < istop; i++) { *bp >>= 1; - *bp &= 0x55; + *bp++ &= 0x55; } break; } + case 4: { - png_bytep bp; - png_byte mask; + png_bytep bp = row; png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + png_byte mask = (png_byte)((((int)0xf0 >> shift[0]) & (int)0xf0) | + (png_byte)((int)0xf >> shift[0])); - mask = (png_byte)(((int)0xf0 >> shift[0]) & (int)0xf0) | - (png_byte)((int)0xf >> shift[0]); - for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++) + for (i = 0; i < istop; i++) { *bp >>= shift[0]; - *bp &= mask; + *bp++ &= mask; } break; } + case 8: { - png_bytep bp; + png_bytep bp = row; png_uint_32 i; + png_uint_32 istop = row_width * channels; - for (bp = row, i = 0; i < row_info->width; i++) + for (i = 0; i < istop; i++) { - for (c = 0; c < (int)row_info->channels; c++, bp++) - { - *bp >>= shift[c]; - } + *bp++ >>= shift[i%channels]; } break; } + case 16: { - png_bytep bp; - png_size_t i; + png_bytep bp = row; + png_uint_32 i; + png_uint_32 istop = channels * row_width; - for (bp = row, i = 0; i < row_info->width; i++) + for (i = 0; i < istop; i++) { - for (c = 0; c < (int)row_info->channels; c++, bp += 2) - { - value = (png_uint_16)((*bp << 8) + *(bp + 1)); - value >>= shift[c]; - *bp = (png_byte)(value >> 8); - *(bp + 1) = (png_byte)(value & 0xff); - } + value = (png_uint_16)((*bp << 8) + *(bp + 1)); + value >>= shift[i%channels]; + *bp++ = (png_byte)(value >> 8); + *bp++ = (png_byte)(value & 0xff); } break; } @@ -1387,50 +1745,51 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits) } #endif -#if defined(PNG_READ_16_TO_8_SUPPORTED) -/* chop rows of bit depth 16 down to 8 */ -void +#ifdef PNG_READ_16_TO_8_SUPPORTED +/* Chop rows of bit depth 16 down to 8 */ +void /* PRIVATE */ png_do_chop(png_row_infop row_info, png_bytep row) { - png_debug(1, "in png_do_chop\n"); -#if defined(PNG_USELESS_TESTS_SUPPORTED) - if (row != NULL && row_info != NULL && row_info->bit_depth == 16) -#else + png_debug(1, "in png_do_chop"); + if (row_info->bit_depth == 16) -#endif { - png_bytep sp, dp; + png_bytep sp = row; + png_bytep dp = row; png_uint_32 i; + png_uint_32 istop = row_info->width * row_info->channels; - sp = row; - dp = row; - for (i = 0; i < row_info->width * row_info->channels; i++, sp += 2, dp++) + for (i = 0; i> 8)) >> 8; +#ifdef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED + /* This does a more accurate scaling of the 16-bit color + * value, rather than a simple low-byte truncation. + * + * What the ideal calculation should be: + * *dp = (((((png_uint_32)(*sp) << 8) | + * (png_uint_32)(*(sp + 1))) * 255 + 127) + * / (png_uint_32)65535L; + * + * GRR: no, I think this is what it really should be: + * *dp = (((((png_uint_32)(*sp) << 8) | + * (png_uint_32)(*(sp + 1))) + 128L) + * / (png_uint_32)257L; + * + * GRR: here's the exact calculation with shifts: + * temp = (((png_uint_32)(*sp) << 8) | + * (png_uint_32)(*(sp + 1))) + 128L; + * *dp = (temp - (temp >> 8)) >> 8; + * + * Approximate calculation with shift/add instead of multiply/divide: + * *dp = ((((png_uint_32)(*sp) << 8) | + * (png_uint_32)((int)(*(sp + 1)) - *sp)) + 128) >> 8; + * + * What we actually do to avoid extra shifting and conversion: + */ - - * Approximate calculation with shift/add instead of multiply/divide: - *dp = ((((png_uint_32)(*sp) << 8) | - (png_uint_32)((int)(*(sp + 1)) - *sp)) + 128) >> 8; - - * What we actually do to avoid extra shifting and conversion: */ *dp = *sp + ((((int)(*(sp + 1)) - *sp) > 128) ? 1 : 0); #else + /* Simply discard the low order byte */ *dp = *sp; #endif } @@ -1441,26 +1800,25 @@ png_do_chop(png_row_infop row_info, png_bytep row) } #endif -#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) -void +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED +void /* PRIVATE */ png_do_read_swap_alpha(png_row_infop row_info, png_bytep row) { - png_debug(1, "in png_do_read_swap_alpha\n"); -#if defined(PNG_USELESS_TESTS_SUPPORTED) - if (row != NULL && row_info != NULL) -#endif + png_debug(1, "in png_do_read_swap_alpha"); + { + png_uint_32 row_width = row_info->width; if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) { /* This converts from RGBA to ARGB */ if (row_info->bit_depth == 8) { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_byte save; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { save = *(--sp); *(--dp) = *(--sp); @@ -1472,12 +1830,12 @@ png_do_read_swap_alpha(png_row_infop row_info, png_bytep row) /* This converts from RRGGBBAA to AARRGGBB */ else { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_byte save[2]; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { save[0] = *(--sp); save[1] = *(--sp); @@ -1497,12 +1855,12 @@ png_do_read_swap_alpha(png_row_infop row_info, png_bytep row) /* This converts from GA to AG */ if (row_info->bit_depth == 8) { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_byte save; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { save = *(--sp); *(--dp) = *(--sp); @@ -1512,12 +1870,12 @@ png_do_read_swap_alpha(png_row_infop row_info, png_bytep row) /* This converts from GGAA to AAGG */ else { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_byte save[2]; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { save[0] = *(--sp); save[1] = *(--sp); @@ -1532,49 +1890,60 @@ png_do_read_swap_alpha(png_row_infop row_info, png_bytep row) } #endif -#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) -void +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED +void /* PRIVATE */ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row) { - png_debug(1, "in png_do_read_invert_alpha\n"); -#if defined(PNG_USELESS_TESTS_SUPPORTED) - if (row != NULL && row_info != NULL) -#endif + png_debug(1, "in png_do_read_invert_alpha"); + { + png_uint_32 row_width = row_info->width; if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) { /* This inverts the alpha channel in RGBA */ if (row_info->bit_depth == 8) { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { - *(--dp) = 255 - *(--sp); + *(--dp) = (png_byte)(255 - *(--sp)); + +/* This does nothing: *(--dp) = *(--sp); *(--dp) = *(--sp); *(--dp) = *(--sp); + We can replace it with: +*/ + sp-=3; + dp=sp; } } /* This inverts the alpha channel in RRGGBBAA */ else { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { - *(--dp) = 255 - *(--sp); - *(--dp) = 255 - *(--sp); + *(--dp) = (png_byte)(255 - *(--sp)); + *(--dp) = (png_byte)(255 - *(--sp)); + +/* This does nothing: *(--dp) = *(--sp); *(--dp) = *(--sp); *(--dp) = *(--sp); *(--dp) = *(--sp); *(--dp) = *(--sp); *(--dp) = *(--sp); + We can replace it with: +*/ + sp-=6; + dp=sp; } } } @@ -1583,29 +1952,33 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row) /* This inverts the alpha channel in GA */ if (row_info->bit_depth == 8) { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { - *(--dp) = 255 - *(--sp); + *(--dp) = (png_byte)(255 - *(--sp)); *(--dp) = *(--sp); } } /* This inverts the alpha channel in GGAA */ else { - png_bytep sp, dp; + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; png_uint_32 i; - for (i = 0, sp = dp = row + row_info->rowbytes; - i < row_info->width; i++) + for (i = 0; i < row_width; i++) { - *(--dp) = 255 - *(--sp); - *(--dp) = 255 - *(--sp); + *(--dp) = (png_byte)(255 - *(--sp)); + *(--dp) = (png_byte)(255 - *(--sp)); +/* *(--dp) = *(--sp); *(--dp) = *(--sp); +*/ + sp-=2; + dp=sp; } } } @@ -1613,106 +1986,218 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row) } #endif -#if defined(PNG_READ_FILLER_SUPPORTED) +#ifdef PNG_READ_FILLER_SUPPORTED /* Add filler channel if we have RGB color */ -void +void /* PRIVATE */ png_do_read_filler(png_row_infop row_info, png_bytep row, png_uint_32 filler, png_uint_32 flags) { - png_bytep sp, dp; png_uint_32 i; + png_uint_32 row_width = row_info->width; + + png_byte hi_filler = (png_byte)((filler>>8) & 0xff); + png_byte lo_filler = (png_byte)(filler & 0xff); + + png_debug(1, "in png_do_read_filler"); - png_debug(1, "in png_do_read_filler\n"); if ( -#if defined(PNG_USELESS_TESTS_SUPPORTED) - row != NULL && row_info != NULL && -#endif - row_info->color_type == PNG_COLOR_TYPE_RGB && row_info->bit_depth == 8) + row_info->color_type == PNG_COLOR_TYPE_GRAY) { - /* This changes the data from RGB to RGBX */ - if (flags & PNG_FLAG_FILLER_AFTER) + if (row_info->bit_depth == 8) { - for (i = 1, sp = row + (png_size_t)row_info->width * 3, - dp = row + (png_size_t)row_info->width * 4; - i < row_info->width; - i++) + /* This changes the data from G to GX */ + if (flags & PNG_FLAG_FILLER_AFTER) { - *(--dp) = (png_byte)filler; - *(--dp) = *(--sp); - *(--dp) = *(--sp); - *(--dp) = *(--sp); + png_bytep sp = row + (png_size_t)row_width; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 1; i < row_width; i++) + { + *(--dp) = lo_filler; + *(--dp) = *(--sp); + } + *(--dp) = lo_filler; + row_info->channels = 2; + row_info->pixel_depth = 16; + row_info->rowbytes = row_width * 2; + } + /* This changes the data from G to XG */ + else + { + png_bytep sp = row + (png_size_t)row_width; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = lo_filler; + } + row_info->channels = 2; + row_info->pixel_depth = 16; + row_info->rowbytes = row_width * 2; + } + } + else if (row_info->bit_depth == 16) + { + /* This changes the data from GG to GGXX */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + png_bytep sp = row + (png_size_t)row_width * 2; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 1; i < row_width; i++) + { + *(--dp) = hi_filler; + *(--dp) = lo_filler; + *(--dp) = *(--sp); + *(--dp) = *(--sp); + } + *(--dp) = hi_filler; + *(--dp) = lo_filler; + row_info->channels = 2; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + } + /* This changes the data from GG to XXGG */ + else + { + png_bytep sp = row + (png_size_t)row_width * 2; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = hi_filler; + *(--dp) = lo_filler; + } + row_info->channels = 2; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; } - *(--dp) = (png_byte)filler; - row_info->channels = 4; - row_info->pixel_depth = 32; - row_info->rowbytes = row_info->width * 4; } + } /* COLOR_TYPE == GRAY */ + else if (row_info->color_type == PNG_COLOR_TYPE_RGB) + { + if (row_info->bit_depth == 8) + { + /* This changes the data from RGB to RGBX */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + png_bytep sp = row + (png_size_t)row_width * 3; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 1; i < row_width; i++) + { + *(--dp) = lo_filler; + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + } + *(--dp) = lo_filler; + row_info->channels = 4; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + } /* This changes the data from RGB to XRGB */ - else + else + { + png_bytep sp = row + (png_size_t)row_width * 3; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = lo_filler; + } + row_info->channels = 4; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + } + } + else if (row_info->bit_depth == 16) { - for (i = 0, sp = row + (png_size_t)row_info->width * 3, - dp = row + (png_size_t)row_info->width * 4; - i < row_info->width; - i++) + /* This changes the data from RRGGBB to RRGGBBXX */ + if (flags & PNG_FLAG_FILLER_AFTER) { - *(--dp) = *(--sp); - *(--dp) = *(--sp); - *(--dp) = *(--sp); - *(--dp) = (png_byte)filler; + png_bytep sp = row + (png_size_t)row_width * 6; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 1; i < row_width; i++) + { + *(--dp) = hi_filler; + *(--dp) = lo_filler; + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + } + *(--dp) = hi_filler; + *(--dp) = lo_filler; + row_info->channels = 4; + row_info->pixel_depth = 64; + row_info->rowbytes = row_width * 8; + } + /* This changes the data from RRGGBB to XXRRGGBB */ + else + { + png_bytep sp = row + (png_size_t)row_width * 6; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = hi_filler; + *(--dp) = lo_filler; + } + row_info->channels = 4; + row_info->pixel_depth = 64; + row_info->rowbytes = row_width * 8; } - row_info->channels = 4; - row_info->pixel_depth = 32; - row_info->rowbytes = row_info->width * 4; } - } + } /* COLOR_TYPE == RGB */ } #endif -#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) -/* expand grayscale files to RGB, with or without alpha */ -void +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED +/* Expand grayscale files to RGB, with or without alpha */ +void /* PRIVATE */ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row) { - png_bytep sp, dp; png_uint_32 i; + png_uint_32 row_width = row_info->width; + + png_debug(1, "in png_do_gray_to_rgb"); - png_debug(1, "in png_do_gray_to_rgb\n"); if (row_info->bit_depth >= 8 && -#if defined(PNG_USELESS_TESTS_SUPPORTED) - row != NULL && row_info != NULL && -#endif !(row_info->color_type & PNG_COLOR_MASK_COLOR)) { if (row_info->color_type == PNG_COLOR_TYPE_GRAY) { if (row_info->bit_depth == 8) { - for (i = 0, sp = row + (png_size_t)row_info->width - 1, - dp = row + (png_size_t)row_info->width * 3 - 1; - i < row_info->width; - i++) + png_bytep sp = row + (png_size_t)row_width - 1; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) { *(dp--) = *sp; *(dp--) = *sp; - *(dp--) = *sp; - sp--; + *(dp--) = *(sp--); } } else { - for (i = 0, sp = row + (png_size_t)row_info->width * 2 - 1, - dp = row + (png_size_t)row_info->width * 6 - 1; - i < row_info->width; - i++) + png_bytep sp = row + (png_size_t)row_width * 2 - 1; + png_bytep dp = sp + (png_size_t)row_width * 4; + for (i = 0; i < row_width; i++) { *(dp--) = *sp; *(dp--) = *(sp - 1); *(dp--) = *sp; *(dp--) = *(sp - 1); - *(dp--) = *sp; - *(dp--) = *(sp - 1); - sp--; - sp--; + *(dp--) = *(sp--); + *(dp--) = *(sp--); } } } @@ -1720,24 +2205,21 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row) { if (row_info->bit_depth == 8) { - for (i = 0, sp = row + (png_size_t)row_info->width * 2 - 1, - dp = row + (png_size_t)row_info->width * 4 - 1; - i < row_info->width; - i++) + png_bytep sp = row + (png_size_t)row_width * 2 - 1; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) { *(dp--) = *(sp--); *(dp--) = *sp; *(dp--) = *sp; - *(dp--) = *sp; - sp--; + *(dp--) = *(sp--); } } else { - for (i = 0, sp = row + (png_size_t)row_info->width * 4 - 1, - dp = row + (png_size_t)row_info->width * 8 - 1; - i < row_info->width; - i++) + png_bytep sp = row + (png_size_t)row_width * 4 - 1; + png_bytep dp = sp + (png_size_t)row_width * 4; + for (i = 0; i < row_width; i++) { *(dp--) = *(sp--); *(dp--) = *(sp--); @@ -1745,10 +2227,8 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row) *(dp--) = *(sp - 1); *(dp--) = *sp; *(dp--) = *(sp - 1); - *(dp--) = *sp; - *(dp--) = *(sp - 1); - sp--; - sp--; + *(dp--) = *(sp--); + *(dp--) = *(sp--); } } } @@ -1756,18 +2236,273 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row) row_info->color_type |= PNG_COLOR_MASK_COLOR; row_info->pixel_depth = (png_byte)(row_info->channels * row_info->bit_depth); - row_info->rowbytes = ((row_info->width * - row_info->pixel_depth + 7) >> 3); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); } } #endif +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +/* Reduce RGB files to grayscale, with or without alpha + * using the equation given in Poynton's ColorFAQ at + * (THIS LINK IS DEAD June 2008) + * New link: + * + * Charles Poynton poynton at poynton.com + * + * Y = 0.212671 * R + 0.715160 * G + 0.072169 * B + * + * We approximate this with + * + * Y = 0.21268 * R + 0.7151 * G + 0.07217 * B + * + * which can be expressed with integers as + * + * Y = (6969 * R + 23434 * G + 2365 * B)/32768 + * + * The calculation is to be done in a linear colorspace. + * + * Other integer coefficents can be used via png_set_rgb_to_gray(). + */ +int /* PRIVATE */ +png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row) + +{ + png_uint_32 i; + + png_uint_32 row_width = row_info->width; + int rgb_error = 0; + + png_debug(1, "in png_do_rgb_to_gray"); + + if ( + (row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + png_uint_32 rc = png_ptr->rgb_to_gray_red_coeff; + png_uint_32 gc = png_ptr->rgb_to_gray_green_coeff; + png_uint_32 bc = png_ptr->rgb_to_gray_blue_coeff; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + { + if (row_info->bit_depth == 8) + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + + for (i = 0; i < row_width; i++) + { + png_byte red = png_ptr->gamma_to_1[*(sp++)]; + png_byte green = png_ptr->gamma_to_1[*(sp++)]; + png_byte blue = png_ptr->gamma_to_1[*(sp++)]; + if (red != green || red != blue) + { + rgb_error |= 1; + *(dp++) = png_ptr->gamma_from_1[ + (rc*red + gc*green + bc*blue)>>15]; + } + else + *(dp++) = *(sp - 1); + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_byte red = *(sp++); + png_byte green = *(sp++); + png_byte blue = *(sp++); + if (red != green || red != blue) + { + rgb_error |= 1; + *(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15); + } + else + *(dp++) = *(sp - 1); + } + } + } + + else /* RGB bit_depth == 16 */ + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_16_to_1 != NULL && + png_ptr->gamma_16_from_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, w; + + red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + + if (red == green && red == blue) + w = red; + else + { + png_uint_16 red_1 = png_ptr->gamma_16_to_1[(red&0xff) >> + png_ptr->gamma_shift][red>>8]; + png_uint_16 green_1 = + png_ptr->gamma_16_to_1[(green&0xff) >> + png_ptr->gamma_shift][green>>8]; + png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >> + png_ptr->gamma_shift][blue>>8]; + png_uint_16 gray16 = (png_uint_16)((rc*red_1 + gc*green_1 + + bc*blue_1)>>15); + w = png_ptr->gamma_16_from_1[(gray16&0xff) >> + png_ptr->gamma_shift][gray16 >> 8]; + rgb_error |= 1; + } + + *(dp++) = (png_byte)((w>>8) & 0xff); + *(dp++) = (png_byte)(w & 0xff); + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, gray16; + + red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + + if (red != green || red != blue) + rgb_error |= 1; + gray16 = (png_uint_16)((rc*red + gc*green + bc*blue)>>15); + *(dp++) = (png_byte)((gray16>>8) & 0xff); + *(dp++) = (png_byte)(gray16 & 0xff); + } + } + } + } + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + if (row_info->bit_depth == 8) + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_byte red = png_ptr->gamma_to_1[*(sp++)]; + png_byte green = png_ptr->gamma_to_1[*(sp++)]; + png_byte blue = png_ptr->gamma_to_1[*(sp++)]; + if (red != green || red != blue) + rgb_error |= 1; + *(dp++) = png_ptr->gamma_from_1 + [(rc*red + gc*green + bc*blue)>>15]; + *(dp++) = *(sp++); /* alpha */ + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_byte red = *(sp++); + png_byte green = *(sp++); + png_byte blue = *(sp++); + if (red != green || red != blue) + rgb_error |= 1; + *(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15); + *(dp++) = *(sp++); /* alpha */ + } + } + } + else /* RGBA bit_depth == 16 */ + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_16_to_1 != NULL && + png_ptr->gamma_16_from_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, w; + + red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + + if (red == green && red == blue) + w = red; + else + { + png_uint_16 red_1 = png_ptr->gamma_16_to_1[(red&0xff) >> + png_ptr->gamma_shift][red>>8]; + png_uint_16 green_1 = + png_ptr->gamma_16_to_1[(green&0xff) >> + png_ptr->gamma_shift][green>>8]; + png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >> + png_ptr->gamma_shift][blue>>8]; + png_uint_16 gray16 = (png_uint_16)((rc * red_1 + + gc * green_1 + bc * blue_1)>>15); + w = png_ptr->gamma_16_from_1[(gray16&0xff) >> + png_ptr->gamma_shift][gray16 >> 8]; + rgb_error |= 1; + } + + *(dp++) = (png_byte)((w>>8) & 0xff); + *(dp++) = (png_byte)(w & 0xff); + *(dp++) = *(sp++); /* alpha */ + *(dp++) = *(sp++); + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, gray16; + red = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2; + if (red != green || red != blue) + rgb_error |= 1; + gray16 = (png_uint_16)((rc*red + gc*green + bc*blue)>>15); + *(dp++) = (png_byte)((gray16>>8) & 0xff); + *(dp++) = (png_byte)(gray16 & 0xff); + *(dp++) = *(sp++); /* alpha */ + *(dp++) = *(sp++); + } + } + } + } + row_info->channels -= (png_byte)2; + row_info->color_type &= ~PNG_COLOR_MASK_COLOR; + row_info->pixel_depth = (png_byte)(row_info->channels * + row_info->bit_depth); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); + } + return rgb_error; +} +#endif + /* Build a grayscale palette. Palette is assumed to be 1 << bit_depth * large of png_color. This lets grayscale images be treated as * paletted. Most useful for gamma correction and simplification * of code. */ -void +void PNGAPI png_build_grayscale_palette(int bit_depth, png_colorp palette) { int num_palette; @@ -1775,7 +2510,8 @@ png_build_grayscale_palette(int bit_depth, png_colorp palette) int i; int v; - png_debug(1, "in png_do_build_grayscale_palette\n"); + png_debug(1, "in png_do_build_grayscale_palette"); + if (palette == NULL) return; @@ -1785,18 +2521,22 @@ png_build_grayscale_palette(int bit_depth, png_colorp palette) num_palette = 2; color_inc = 0xff; break; + case 2: num_palette = 4; color_inc = 0x55; break; + case 4: num_palette = 16; color_inc = 0x11; break; + case 8: num_palette = 256; color_inc = 1; break; + default: num_palette = 0; color_inc = 0; @@ -1811,212 +2551,33 @@ png_build_grayscale_palette(int bit_depth, png_colorp palette) } } -/* This function is currently unused. Do we really need it? */ -#if defined(PNG_READ_DITHER_SUPPORTED) && defined(PNG_CORRECT_PALETTE_SUPPORTED) -void -png_correct_palette(png_structp png_ptr, png_colorp palette, - int num_palette) -{ - png_debug(1, "in png_correct_palette\n"); -#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED) - if ((png_ptr->transformations & (PNG_GAMMA)) && - (png_ptr->transformations & (PNG_BACKGROUND))) - { - png_color back, back_1; - - if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE) - { - back.red = png_ptr->gamma_table[png_ptr->background.red]; - back.green = png_ptr->gamma_table[png_ptr->background.green]; - back.blue = png_ptr->gamma_table[png_ptr->background.blue]; - - back_1.red = png_ptr->gamma_to_1[png_ptr->background.red]; - back_1.green = png_ptr->gamma_to_1[png_ptr->background.green]; - back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue]; - } - else - { - double g; - - g = 1.0 / (png_ptr->background_gamma * png_ptr->screen_gamma); - - if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_SCREEN || - fabs(g - 1.0) < PNG_GAMMA_THRESHOLD) - { - back.red = png_ptr->background.red; - back.green = png_ptr->background.green; - back.blue = png_ptr->background.blue; - } - else - { - back.red = - (png_byte)(pow((double)png_ptr->background.red/255, g) * - 255.0 + 0.5); - back.green = - (png_byte)(pow((double)png_ptr->background.green/255, g) * - 255.0 + 0.5); - back.blue = - (png_byte)(pow((double)png_ptr->background.blue/255, g) * - 255.0 + 0.5); - } - - g = 1.0 / png_ptr->background_gamma; - - back_1.red = - (png_byte)(pow((double)png_ptr->background.red/255, g) * - 255.0 + 0.5); - back_1.green = - (png_byte)(pow((double)png_ptr->background.green/255, g) * - 255.0 + 0.5); - back_1.blue = - (png_byte)(pow((double)png_ptr->background.blue/255, g) * - 255.0 + 0.5); - } - - if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) - { - png_uint_32 i; - - for (i = 0; i < (png_uint_32)num_palette; i++) - { - if (i < png_ptr->num_trans && png_ptr->trans[i] == 0) - { - palette[i] = back; - } - else if (i < png_ptr->num_trans && png_ptr->trans[i] != 0xff) - { - png_byte v, w; - - v = png_ptr->gamma_to_1[png_ptr->palette[i].red]; - png_composite(w, v, png_ptr->trans[i], back_1.red); - palette[i].red = png_ptr->gamma_from_1[w]; - - v = png_ptr->gamma_to_1[png_ptr->palette[i].green]; - png_composite(w, v, png_ptr->trans[i], back_1.green); - palette[i].green = png_ptr->gamma_from_1[w]; - - v = png_ptr->gamma_to_1[png_ptr->palette[i].blue]; - png_composite(w, v, png_ptr->trans[i], back_1.blue); - palette[i].blue = png_ptr->gamma_from_1[w]; - } - else - { - palette[i].red = png_ptr->gamma_table[palette[i].red]; - palette[i].green = png_ptr->gamma_table[palette[i].green]; - palette[i].blue = png_ptr->gamma_table[palette[i].blue]; - } - } - } - else - { - int i; - - for (i = 0; i < num_palette; i++) - { - if (palette[i].red == (png_byte)png_ptr->trans_values.gray) - { - palette[i] = back; - } - else - { - palette[i].red = png_ptr->gamma_table[palette[i].red]; - palette[i].green = png_ptr->gamma_table[palette[i].green]; - palette[i].blue = png_ptr->gamma_table[palette[i].blue]; - } - } - } - } - else -#endif -#if defined(PNG_READ_GAMMA_SUPPORTED) - if (png_ptr->transformations & PNG_GAMMA) - { - int i; - for (i = 0; i < num_palette; i++) - { - palette[i].red = png_ptr->gamma_table[palette[i].red]; - palette[i].green = png_ptr->gamma_table[palette[i].green]; - palette[i].blue = png_ptr->gamma_table[palette[i].blue]; - } - } -#if defined(PNG_READ_BACKGROUND_SUPPORTED) - else -#endif -#endif -#if defined(PNG_READ_BACKGROUND_SUPPORTED) - if (png_ptr->transformations & PNG_BACKGROUND) - { - if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) - { - png_color back; - - back.red = (png_byte)png_ptr->background.red; - back.green = (png_byte)png_ptr->background.green; - back.blue = (png_byte)png_ptr->background.blue; - - for (i = 0; i < (int)png_ptr->num_trans; i++) - { - if (png_ptr->trans[i] == 0) - { - palette[i].red = back.red; - palette[i].green = back.green; - palette[i].blue = back.blue; - } - else if (png_ptr->trans[i] != 0xff) - { - png_composite(palette[i].red, png_ptr->palette[i].red, - png_ptr->trans[i], back.red); - png_composite(palette[i].green, png_ptr->palette[i].green, - png_ptr->trans[i], back.green); - png_composite(palette[i].blue, png_ptr->palette[i].blue, - png_ptr->trans[i], back.blue); - } - } - } - else /* assume grayscale palette (what else could it be?) */ - { - int i; - - for (i = 0; i < num_palette; i++) - { - if (i == (png_byte)png_ptr->trans_values.gray) - { - palette[i].red = (png_byte)png_ptr->background.red; - palette[i].green = (png_byte)png_ptr->background.green; - palette[i].blue = (png_byte)png_ptr->background.blue; - } - } - } - } -#endif -} -#endif - -#if defined(PNG_READ_BACKGROUND_SUPPORTED) +#ifdef PNG_READ_BACKGROUND_SUPPORTED /* Replace any alpha or transparency with the supplied background color. * "background" is already in the screen gamma, while "background_1" is * at a gamma of 1.0. Paletted files have already been taken care of. */ -void +void /* PRIVATE */ png_do_background(png_row_infop row_info, png_bytep row, - png_color_16p trans_values, png_color_16p background, - png_color_16p background_1, + png_color_16p trans_color, png_color_16p background +#ifdef PNG_READ_GAMMA_SUPPORTED + , png_color_16p background_1, png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1, png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1, - png_uint_16pp gamma_16_to_1, int gamma_shift) + png_uint_16pp gamma_16_to_1, int gamma_shift +#endif + ) { png_bytep sp, dp; png_uint_32 i; + png_uint_32 row_width=row_info->width; int shift; - png_debug(1, "in png_do_background\n"); + png_debug(1, "in png_do_background"); + if (background != NULL && -#if defined(PNG_USELESS_TESTS_SUPPORTED) - row != NULL && row_info != NULL && -#endif (!(row_info->color_type & PNG_COLOR_MASK_ALPHA) || - (row_info->color_type != PNG_COLOR_TYPE_PALETTE && trans_values))) + (row_info->color_type != PNG_COLOR_TYPE_PALETTE && trans_color))) { switch (row_info->color_type) { @@ -2028,10 +2589,10 @@ png_do_background(png_row_infop row_info, png_bytep row, { sp = row; shift = 7; - for (i = 0; i < row_info->width; i++) + for (i = 0; i < row_width; i++) { - if ((png_uint_16)((*sp >> shift) & 0x1) - == trans_values->gray) + if ((png_uint_16)((*sp >> shift) & 0x01) + == trans_color->gray) { *sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff); *sp |= (png_byte)(background->gray << shift); @@ -2046,58 +2607,130 @@ png_do_background(png_row_infop row_info, png_bytep row, } break; } + case 2: { - sp = row; - shift = 6; - for (i = 0; i < row_info->width; i++) +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_table != NULL) { - if ((png_uint_16)((*sp >> shift) & 0x3) - == trans_values->gray) + sp = row; + shift = 6; + for (i = 0; i < row_width; i++) { - *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); - *sp |= (png_byte)(background->gray << shift); + if ((png_uint_16)((*sp >> shift) & 0x03) + == trans_color->gray) + { + *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + else + { + png_byte p = (png_byte)((*sp >> shift) & 0x03); + png_byte g = (png_byte)((gamma_table [p | (p << 2) | + (p << 4) | (p << 6)] >> 6) & 0x03); + *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); + *sp |= (png_byte)(g << shift); + } + if (!shift) + { + shift = 6; + sp++; + } + else + shift -= 2; } - if (!shift) + } + else +#endif + { + sp = row; + shift = 6; + for (i = 0; i < row_width; i++) { - shift = 6; - sp++; + if ((png_uint_16)((*sp >> shift) & 0x03) + == trans_color->gray) + { + *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + if (!shift) + { + shift = 6; + sp++; + } + else + shift -= 2; } - else - shift -= 2; } break; } + case 4: { - sp = row; - shift = 4; - for (i = 0; i < row_info->width; i++) +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_table != NULL) { - if ((png_uint_16)((*sp >> shift) & 0xf) - == trans_values->gray) + sp = row; + shift = 4; + for (i = 0; i < row_width; i++) { - *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); - *sp |= (png_byte)(background->gray << shift); + if ((png_uint_16)((*sp >> shift) & 0x0f) + == trans_color->gray) + { + *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + else + { + png_byte p = (png_byte)((*sp >> shift) & 0x0f); + png_byte g = (png_byte)((gamma_table[p | + (p << 4)] >> 4) & 0x0f); + *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); + *sp |= (png_byte)(g << shift); + } + if (!shift) + { + shift = 4; + sp++; + } + else + shift -= 4; } - if (!shift) + } + else +#endif + { + sp = row; + shift = 4; + for (i = 0; i < row_width; i++) { - shift = 4; - sp++; + if ((png_uint_16)((*sp >> shift) & 0x0f) + == trans_color->gray) + { + *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + if (!shift) + { + shift = 4; + sp++; + } + else + shift -= 4; } - else - shift -= 4; } break; } + case 8: { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_table != NULL) { - for (i = 0, sp = row; i < row_info->width; i++, sp++) + sp = row; + for (i = 0; i < row_width; i++, sp++) { - if (*sp == trans_values->gray) + if (*sp == trans_color->gray) { *sp = (png_byte)background->gray; } @@ -2110,9 +2743,10 @@ png_do_background(png_row_infop row_info, png_bytep row, else #endif { - for (i = 0, sp = row; i < row_info->width; i++, sp++) + sp = row; + for (i = 0; i < row_width; i++, sp++) { - if (*sp == trans_values->gray) + if (*sp == trans_color->gray) { *sp = (png_byte)background->gray; } @@ -2120,19 +2754,21 @@ png_do_background(png_row_infop row_info, png_bytep row, } break; } + case 16: { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_16 != NULL) { - for (i = 0, sp = row; i < row_info->width; i++, sp += 2) + sp = row; + for (i = 0; i < row_width; i++, sp += 2) { png_uint_16 v; - v = ((png_uint_16)(*sp) << 8) + *(sp + 1); - if (v == trans_values->gray) + v = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + if (v == trans_color->gray) { - /* background is already in screen gamma */ + /* Background is already in screen gamma */ *sp = (png_byte)((background->gray >> 8) & 0xff); *(sp + 1) = (png_byte)(background->gray & 0xff); } @@ -2147,12 +2783,13 @@ png_do_background(png_row_infop row_info, png_bytep row, else #endif { - for (i = 0, sp = row; i < row_info->width; i++, sp += 2) + sp = row; + for (i = 0; i < row_width; i++, sp += 2) { png_uint_16 v; - v = ((png_uint_16)(*sp) << 8) + *(sp + 1); - if (v == trans_values->gray) + v = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + if (v == trans_color->gray) { *sp = (png_byte)((background->gray >> 8) & 0xff); *(sp + 1) = (png_byte)(background->gray & 0xff); @@ -2164,18 +2801,20 @@ png_do_background(png_row_infop row_info, png_bytep row, } break; } + case PNG_COLOR_TYPE_RGB: { if (row_info->bit_depth == 8) { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_table != NULL) { - for (i = 0, sp = row; i < row_info->width; i++, sp += 3) + sp = row; + for (i = 0; i < row_width; i++, sp += 3) { - if (*sp == trans_values->red && - *(sp + 1) == trans_values->green && - *(sp + 2) == trans_values->blue) + if (*sp == trans_color->red && + *(sp + 1) == trans_color->green && + *(sp + 2) == trans_color->blue) { *sp = (png_byte)background->red; *(sp + 1) = (png_byte)background->green; @@ -2192,11 +2831,12 @@ png_do_background(png_row_infop row_info, png_bytep row, else #endif { - for (i = 0, sp = row; i < row_info->width; i++, sp += 3) + sp = row; + for (i = 0; i < row_width; i++, sp += 3) { - if (*sp == trans_values->red && - *(sp + 1) == trans_values->green && - *(sp + 2) == trans_values->blue) + if (*sp == trans_color->red && + *(sp + 1) == trans_color->green && + *(sp + 2) == trans_color->blue) { *sp = (png_byte)background->red; *(sp + 1) = (png_byte)background->green; @@ -2207,20 +2847,19 @@ png_do_background(png_row_infop row_info, png_bytep row, } else /* if (row_info->bit_depth == 16) */ { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_16 != NULL) { - for (i = 0, sp = row; i < row_info->width; i++, sp += 6) + sp = row; + for (i = 0; i < row_width; i++, sp += 6) { - png_uint_16 r, g, b; - - r = ((png_uint_16)(*sp) << 8) + *(sp + 1); - g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); - b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5); - if (r == trans_values->red && g == trans_values->green && - b == trans_values->blue) + png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); + png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5)); + if (r == trans_color->red && g == trans_color->green && + b == trans_color->blue) { - /* background is already in screen gamma */ + /* Background is already in screen gamma */ *sp = (png_byte)((background->red >> 8) & 0xff); *(sp + 1) = (png_byte)(background->red & 0xff); *(sp + 2) = (png_byte)((background->green >> 8) & 0xff); @@ -2230,8 +2869,7 @@ png_do_background(png_row_infop row_info, png_bytep row, } else { - png_uint_16 v; - v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; + png_uint_16 v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; *sp = (png_byte)((v >> 8) & 0xff); *(sp + 1) = (png_byte)(v & 0xff); v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)]; @@ -2246,15 +2884,15 @@ png_do_background(png_row_infop row_info, png_bytep row, else #endif { - for (i = 0, sp = row; i < row_info->width; i++, sp += 6) + sp = row; + for (i = 0; i < row_width; i++, sp += 6) { - png_uint_16 r, g, b; + png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp+1)); + png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); + png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5)); - r = ((png_uint_16)(*sp) << 8) + *(sp + 1); - g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); - b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5); - if (r == trans_values->red && g == trans_values->green && - b == trans_values->blue) + if (r == trans_color->red && g == trans_color->green && + b == trans_color->blue) { *sp = (png_byte)((background->red >> 8) & 0xff); *(sp + 1) = (png_byte)(background->red & 0xff); @@ -2268,27 +2906,28 @@ png_do_background(png_row_infop row_info, png_bytep row, } break; } + case PNG_COLOR_TYPE_GRAY_ALPHA: { if (row_info->bit_depth == 8) { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_to_1 != NULL && gamma_from_1 != NULL && gamma_table != NULL) { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 2, dp++) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 2, dp++) { - png_uint_16 a; + png_uint_16 a = *(sp + 1); - a = *(sp + 1); if (a == 0xff) { *dp = gamma_table[*sp]; } else if (a == 0) { - /* background is already in screen gamma */ + /* Background is already in screen gamma */ *dp = (png_byte)background->gray; } else @@ -2304,16 +2943,17 @@ png_do_background(png_row_infop row_info, png_bytep row, else #endif { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 2, dp++) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 2, dp++) { - png_byte a; + png_byte a = *(sp + 1); - a = *(sp + 1); if (a == 0xff) { *dp = *sp; } +#ifdef PNG_READ_GAMMA_SUPPORTED else if (a == 0) { *dp = (png_byte)background->gray; @@ -2322,21 +2962,24 @@ png_do_background(png_row_infop row_info, png_bytep row, { png_composite(*dp, *sp, a, background_1->gray); } +#else + *dp = (png_byte)background->gray; +#endif } } } else /* if (png_ptr->bit_depth == 16) */ { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_16 != NULL && gamma_16_from_1 != NULL && gamma_16_to_1 != NULL) { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 4, dp += 2) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 2) { - png_uint_16 a; + png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); - a = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); if (a == (png_uint_16)0xffff) { png_uint_16 v; @@ -2345,12 +2988,17 @@ png_do_background(png_row_infop row_info, png_bytep row, *dp = (png_byte)((v >> 8) & 0xff); *(dp + 1) = (png_byte)(v & 0xff); } +#ifdef PNG_READ_GAMMA_SUPPORTED else if (a == 0) +#else + else +#endif { - /* background is already in screen gamma */ + /* Background is already in screen gamma */ *dp = (png_byte)((background->gray >> 8) & 0xff); *(dp + 1) = (png_byte)(background->gray & 0xff); } +#ifdef PNG_READ_GAMMA_SUPPORTED else { png_uint_16 g, v, w; @@ -2361,54 +3009,61 @@ png_do_background(png_row_infop row_info, png_bytep row, *dp = (png_byte)((w >> 8) & 0xff); *(dp + 1) = (png_byte)(w & 0xff); } +#endif } } else #endif { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 4, dp += 2) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 2) { - png_uint_16 a; - - a = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); + png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); if (a == (png_uint_16)0xffff) { png_memcpy(dp, sp, 2); } +#ifdef PNG_READ_GAMMA_SUPPORTED else if (a == 0) +#else + else +#endif { *dp = (png_byte)((background->gray >> 8) & 0xff); *(dp + 1) = (png_byte)(background->gray & 0xff); } +#ifdef PNG_READ_GAMMA_SUPPORTED else { png_uint_16 g, v; - g = ((png_uint_16)(*sp) << 8) + *(sp + 1); + g = (png_uint_16)(((*sp) << 8) + *(sp + 1)); png_composite_16(v, g, a, background_1->gray); *dp = (png_byte)((v >> 8) & 0xff); *(dp + 1) = (png_byte)(v & 0xff); } +#endif } } } break; } + case PNG_COLOR_TYPE_RGB_ALPHA: { if (row_info->bit_depth == 8) { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_to_1 != NULL && gamma_from_1 != NULL && gamma_table != NULL) { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 4, dp += 3) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 3) { - png_byte a; + png_byte a = *(sp + 3); - a = *(sp + 3); if (a == 0xff) { *dp = gamma_table[*sp]; @@ -2417,7 +3072,7 @@ png_do_background(png_row_infop row_info, png_bytep row, } else if (a == 0) { - /* background is already in screen gamma */ + /* Background is already in screen gamma */ *dp = (png_byte)background->red; *(dp + 1) = (png_byte)background->green; *(dp + 2) = (png_byte)background->blue; @@ -2441,12 +3096,12 @@ png_do_background(png_row_infop row_info, png_bytep row, else #endif { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 4, dp += 3) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 3) { - png_byte a; + png_byte a = *(sp + 3); - a = *(sp + 3); if (a == 0xff) { *dp = *sp; @@ -2472,17 +3127,16 @@ png_do_background(png_row_infop row_info, png_bytep row, } else /* if (row_info->bit_depth == 16) */ { -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED if (gamma_16 != NULL && gamma_16_from_1 != NULL && gamma_16_to_1 != NULL) { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 8, dp += 6) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 8, dp += 6) { - png_uint_16 a; - - a = (png_uint_16)(((png_uint_16)(*(sp + 6)) << 8) + - (png_uint_16)(*(sp + 7))); + png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6)) + << 8) + (png_uint_16)(*(sp + 7))); if (a == (png_uint_16)0xffff) { png_uint_16 v; @@ -2499,7 +3153,7 @@ png_do_background(png_row_infop row_info, png_bytep row, } else if (a == 0) { - /* background is already in screen gamma */ + /* Background is already in screen gamma */ *dp = (png_byte)((background->red >> 8) & 0xff); *(dp + 1) = (png_byte)(background->red & 0xff); *(dp + 2) = (png_byte)((background->green >> 8) & 0xff); @@ -2512,17 +3166,17 @@ png_do_background(png_row_infop row_info, png_bytep row, png_uint_16 v, w, x; v = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp]; - png_composite_16(w, v, a, background->red); + png_composite_16(w, v, a, background_1->red); x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8]; *dp = (png_byte)((x >> 8) & 0xff); *(dp + 1) = (png_byte)(x & 0xff); v = gamma_16_to_1[*(sp + 3) >> gamma_shift][*(sp + 2)]; - png_composite_16(w, v, a, background->green); + png_composite_16(w, v, a, background_1->green); x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8]; *(dp + 2) = (png_byte)((x >> 8) & 0xff); *(dp + 3) = (png_byte)(x & 0xff); v = gamma_16_to_1[*(sp + 5) >> gamma_shift][*(sp + 4)]; - png_composite_16(w, v, a, background->blue); + png_composite_16(w, v, a, background_1->blue); x = gamma_16_from_1[(w & 0xff) >> gamma_shift][w >> 8]; *(dp + 4) = (png_byte)((x >> 8) & 0xff); *(dp + 5) = (png_byte)(x & 0xff); @@ -2532,13 +3186,12 @@ png_do_background(png_row_infop row_info, png_bytep row, else #endif { - for (i = 0, sp = row, dp = row; - i < row_info->width; i++, sp += 8, dp += 6) + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 8, dp += 6) { - png_uint_16 a; - - a = (png_uint_16)(((png_uint_16)(*(sp + 6)) << 8) + - (png_uint_16)(*(sp + 7))); + png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6)) + << 8) + (png_uint_16)(*(sp + 7))); if (a == (png_uint_16)0xffff) { png_memcpy(dp, sp, 6); @@ -2554,11 +3207,13 @@ png_do_background(png_row_infop row_info, png_bytep row, } else { - png_uint_16 r, g, b, v; + png_uint_16 v; - r = ((png_uint_16)(*sp) << 8) + *(sp + 1); - g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); - b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5); + png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8) + + *(sp + 3)); + png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8) + + *(sp + 5)); png_composite_16(v, r, a, background->red); *dp = (png_byte)((v >> 8) & 0xff); @@ -2583,33 +3238,31 @@ png_do_background(png_row_infop row_info, png_bytep row, row_info->channels--; row_info->pixel_depth = (png_byte)(row_info->channels * row_info->bit_depth); - row_info->rowbytes = ((row_info->width * - row_info->pixel_depth + 7) >> 3); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); } } } #endif -#if defined(PNG_READ_GAMMA_SUPPORTED) +#ifdef PNG_READ_GAMMA_SUPPORTED /* Gamma correct the image, avoiding the alpha channel. Make sure - * you do this after you deal with the trasparency issue on grayscale - * or rgb images. If your bit depth is 8, use gamma_table, if it + * you do this after you deal with the transparency issue on grayscale + * or RGB images. If your bit depth is 8, use gamma_table, if it * is 16, use gamma_16_table and gamma_shift. Build these with * build_gamma_table(). */ -void +void /* PRIVATE */ png_do_gamma(png_row_infop row_info, png_bytep row, png_bytep gamma_table, png_uint_16pp gamma_16_table, int gamma_shift) { png_bytep sp; png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_gamma"); - png_debug(1, "in png_do_gamma\n"); if ( -#if defined(PNG_USELESS_TESTS_SUPPORTED) - row != NULL && row_info != NULL && -#endif ((row_info->bit_depth <= 8 && gamma_table != NULL) || (row_info->bit_depth == 16 && gamma_16_table != NULL))) { @@ -2619,7 +3272,8 @@ png_do_gamma(png_row_infop row_info, png_bytep row, { if (row_info->bit_depth == 8) { - for (i = 0, sp = row; i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { *sp = gamma_table[*sp]; sp++; @@ -2631,7 +3285,8 @@ png_do_gamma(png_row_infop row_info, png_bytep row, } else /* if (row_info->bit_depth == 16) */ { - for (i = 0, sp = row; i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { png_uint_16 v; @@ -2651,12 +3306,13 @@ png_do_gamma(png_row_infop row_info, png_bytep row, } break; } + case PNG_COLOR_TYPE_RGB_ALPHA: { if (row_info->bit_depth == 8) { - for (i = 0, sp = row; - i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { *sp = gamma_table[*sp]; sp++; @@ -2669,12 +3325,10 @@ png_do_gamma(png_row_infop row_info, png_bytep row, } else /* if (row_info->bit_depth == 16) */ { - for (i = 0, sp = row; - i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { - png_uint_16 v; - - v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; *sp = (png_byte)((v >> 8) & 0xff); *(sp + 1) = (png_byte)(v & 0xff); sp += 2; @@ -2690,12 +3344,13 @@ png_do_gamma(png_row_infop row_info, png_bytep row, } break; } + case PNG_COLOR_TYPE_GRAY_ALPHA: { if (row_info->bit_depth == 8) { - for (i = 0, sp = row; - i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { *sp = gamma_table[*sp]; sp += 2; @@ -2703,12 +3358,10 @@ png_do_gamma(png_row_infop row_info, png_bytep row, } else /* if (row_info->bit_depth == 16) */ { - for (i = 0, sp = row; - i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { - png_uint_16 v; - - v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; *sp = (png_byte)((v >> 8) & 0xff); *(sp + 1) = (png_byte)(v & 0xff); sp += 4; @@ -2716,51 +3369,58 @@ png_do_gamma(png_row_infop row_info, png_bytep row, } break; } + case PNG_COLOR_TYPE_GRAY: { if (row_info->bit_depth == 2) { - for (i = 0, sp = row; i < row_info->width; i += 4) + sp = row; + for (i = 0; i < row_width; i += 4) { int a = *sp & 0xc0; int b = *sp & 0x30; int c = *sp & 0x0c; int d = *sp & 0x03; - *sp = ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)]) ) & 0xc0)| - ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)| - ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)| - ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) ); + *sp = (png_byte)( + ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)]) ) & 0xc0)| + ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)| + ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)| + ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) )); sp++; } } + if (row_info->bit_depth == 4) { - for (i = 0, sp = row; i < row_info->width; i += 2) + sp = row; + for (i = 0; i < row_width; i += 2) { int msb = *sp & 0xf0; int lsb = *sp & 0x0f; - *sp = (((int)gamma_table[msb | (msb >> 4)]) & 0xf0) | - (((int)gamma_table[(lsb << 4) | lsb]) >> 4); + *sp = (png_byte)((((int)gamma_table[msb | (msb >> 4)]) & 0xf0) + | (((int)gamma_table[(lsb << 4) | lsb]) >> 4)); sp++; } } + else if (row_info->bit_depth == 8) { - for (i = 0, sp = row; i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { *sp = gamma_table[*sp]; sp++; } } + else if (row_info->bit_depth == 16) { - for (i = 0, sp = row; i < row_info->width; i++) + sp = row; + for (i = 0; i < row_width; i++) { - png_uint_16 v; - - v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; *sp = (png_byte)((v >> 8) & 0xff); *(sp + 1) = (png_byte)(v & 0xff); sp += 2; @@ -2773,23 +3433,22 @@ png_do_gamma(png_row_infop row_info, png_bytep row, } #endif -#if defined(PNG_READ_EXPAND_SUPPORTED) -/* Expands a palette row to an rgb or rgba row depending +#ifdef PNG_READ_EXPAND_SUPPORTED +/* Expands a palette row to an RGB or RGBA row depending * upon whether you supply trans and num_trans. */ -void +void /* PRIVATE */ png_do_expand_palette(png_row_infop row_info, png_bytep row, - png_colorp palette, png_bytep trans, int num_trans) + png_colorp palette, png_bytep trans_alpha, int num_trans) { int shift, value; png_bytep sp, dp; png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_expand_palette"); - png_debug(1, "in png_do_expand_palette\n"); if ( -#if defined(PNG_USELESS_TESTS_SUPPORTED) - row != NULL && row_info != NULL && -#endif row_info->color_type == PNG_COLOR_TYPE_PALETTE) { if (row_info->bit_depth < 8) @@ -2798,12 +3457,12 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row, { case 1: { - sp = row + (png_size_t)((row_info->width - 1) >> 3); - dp = row + (png_size_t)row_info->width - 1; - shift = 7 - (int)((row_info->width + 7) & 7); - for (i = 0; i < row_info->width; i++) + sp = row + (png_size_t)((row_width - 1) >> 3); + dp = row + (png_size_t)row_width - 1; + shift = 7 - (int)((row_width + 7) & 0x07); + for (i = 0; i < row_width; i++) { - if ((*sp >> shift) & 0x1) + if ((*sp >> shift) & 0x01) *dp = 1; else *dp = 0; @@ -2819,14 +3478,15 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row, } break; } + case 2: { - sp = row + (png_size_t)((row_info->width - 1) >> 2); - dp = row + (png_size_t)row_info->width - 1; - shift = (int)((3 - ((row_info->width + 3) & 3)) << 1); - for (i = 0; i < row_info->width; i++) + sp = row + (png_size_t)((row_width - 1) >> 2); + dp = row + (png_size_t)row_width - 1; + shift = (int)((3 - ((row_width + 3) & 0x03)) << 1); + for (i = 0; i < row_width; i++) { - value = (*sp >> shift) & 0x3; + value = (*sp >> shift) & 0x03; *dp = (png_byte)value; if (shift == 6) { @@ -2840,14 +3500,15 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row, } break; } + case 4: { - sp = row + (png_size_t)((row_info->width - 1) >> 1); - dp = row + (png_size_t)row_info->width - 1; - shift = (int)((row_info->width & 1) << 2); - for (i = 0; i < row_info->width; i++) + sp = row + (png_size_t)((row_width - 1) >> 1); + dp = row + (png_size_t)row_width - 1; + shift = (int)((row_width & 0x01) << 2); + for (i = 0; i < row_width; i++) { - value = (*sp >> shift) & 0xf; + value = (*sp >> shift) & 0x0f; *dp = (png_byte)value; if (shift == 4) { @@ -2864,23 +3525,23 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row, } row_info->bit_depth = 8; row_info->pixel_depth = 8; - row_info->rowbytes = row_info->width; + row_info->rowbytes = row_width; } switch (row_info->bit_depth) { case 8: { - if (trans != NULL) + if (trans_alpha != NULL) { - sp = row + (png_size_t)row_info->width - 1; - dp = row + (png_size_t)(row_info->width << 2) - 1; + sp = row + (png_size_t)row_width - 1; + dp = row + (png_size_t)(row_width << 2) - 1; - for (i = 0; i < row_info->width; i++) + for (i = 0; i < row_width; i++) { if ((int)(*sp) >= num_trans) *dp-- = 0xff; else - *dp-- = trans[*sp]; + *dp-- = trans_alpha[*sp]; *dp-- = palette[*sp].blue; *dp-- = palette[*sp].green; *dp-- = palette[*sp].red; @@ -2888,25 +3549,26 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row, } row_info->bit_depth = 8; row_info->pixel_depth = 32; - row_info->rowbytes = row_info->width * 4; + row_info->rowbytes = row_width * 4; row_info->color_type = 6; row_info->channels = 4; } else { - sp = row + (png_size_t)row_info->width - 1; - dp = row + (png_size_t)(row_info->width * 3) - 1; + sp = row + (png_size_t)row_width - 1; + dp = row + (png_size_t)(row_width * 3) - 1; - for (i = 0; i < row_info->width; i++) + for (i = 0; i < row_width; i++) { *dp-- = palette[*sp].blue; *dp-- = palette[*sp].green; *dp-- = palette[*sp].red; sp--; } + row_info->bit_depth = 8; row_info->pixel_depth = 24; - row_info->rowbytes = row_info->width * 3; + row_info->rowbytes = row_width * 3; row_info->color_type = 2; row_info->channels = 3; } @@ -2916,25 +3578,24 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row, } } -/* If the bit depth < 8, it is expanded to 8. Also, if the - * transparency value is supplied, an alpha channel is built. +/* If the bit depth < 8, it is expanded to 8. Also, if the already + * expanded transparency value is supplied, an alpha channel is built. */ -void +void /* PRIVATE */ png_do_expand(png_row_infop row_info, png_bytep row, png_color_16p trans_value) { int shift, value; png_bytep sp, dp; png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_expand"); - png_debug(1, "in png_do_expand\n"); -#if defined(PNG_USELESS_TESTS_SUPPORTED) - if (row != NULL && row_info != NULL) -#endif { if (row_info->color_type == PNG_COLOR_TYPE_GRAY) { - png_uint_16 gray = trans_value ? trans_value->gray : 0; + png_uint_16 gray = (png_uint_16)(trans_value ? trans_value->gray : 0); if (row_info->bit_depth < 8) { @@ -2942,13 +3603,13 @@ png_do_expand(png_row_infop row_info, png_bytep row, { case 1: { - gray *= 0xff; - sp = row + (png_size_t)((row_info->width - 1) >> 3); - dp = row + (png_size_t)row_info->width - 1; - shift = 7 - (int)((row_info->width + 7) & 7); - for (i = 0; i < row_info->width; i++) + gray = (png_uint_16)((gray&0x01)*0xff); + sp = row + (png_size_t)((row_width - 1) >> 3); + dp = row + (png_size_t)row_width - 1; + shift = 7 - (int)((row_width + 7) & 0x07); + for (i = 0; i < row_width; i++) { - if ((*sp >> shift) & 0x1) + if ((*sp >> shift) & 0x01) *dp = 0xff; else *dp = 0; @@ -2964,15 +3625,16 @@ png_do_expand(png_row_infop row_info, png_bytep row, } break; } + case 2: { - gray *= 0x55; - sp = row + (png_size_t)((row_info->width - 1) >> 2); - dp = row + (png_size_t)row_info->width - 1; - shift = (int)((3 - ((row_info->width + 3) & 3)) << 1); - for (i = 0; i < row_info->width; i++) + gray = (png_uint_16)((gray&0x03)*0x55); + sp = row + (png_size_t)((row_width - 1) >> 2); + dp = row + (png_size_t)row_width - 1; + shift = (int)((3 - ((row_width + 3) & 0x03)) << 1); + for (i = 0; i < row_width; i++) { - value = (*sp >> shift) & 0x3; + value = (*sp >> shift) & 0x03; *dp = (png_byte)(value | (value << 2) | (value << 4) | (value << 6)); if (shift == 6) @@ -2987,15 +3649,16 @@ png_do_expand(png_row_infop row_info, png_bytep row, } break; } + case 4: { - gray *= 0x11; - sp = row + (png_size_t)((row_info->width - 1) >> 1); - dp = row + (png_size_t)row_info->width - 1; - shift = (int)((1 - ((row_info->width + 1) & 1)) << 2); - for (i = 0; i < row_info->width; i++) + gray = (png_uint_16)((gray&0x0f)*0x11); + sp = row + (png_size_t)((row_width - 1) >> 1); + dp = row + (png_size_t)row_width - 1; + shift = (int)((1 - ((row_width + 1) & 0x01)) << 2); + for (i = 0; i < row_width; i++) { - value = (*sp >> shift) & 0xf; + value = (*sp >> shift) & 0x0f; *dp = (png_byte)(value | (value << 4)); if (shift == 4) { @@ -3010,18 +3673,20 @@ png_do_expand(png_row_infop row_info, png_bytep row, break; } } + row_info->bit_depth = 8; row_info->pixel_depth = 8; - row_info->rowbytes = row_info->width; + row_info->rowbytes = row_width; } if (trans_value != NULL) { if (row_info->bit_depth == 8) { - sp = row + (png_size_t)row_info->width - 1; - dp = row + (png_size_t)(row_info->width << 1) - 1; - for (i = 0; i < row_info->width; i++) + gray = gray & 0xff; + sp = row + (png_size_t)row_width - 1; + dp = row + (png_size_t)(row_width << 1) - 1; + for (i = 0; i < row_width; i++) { if (*sp == gray) *dp-- = 0; @@ -3030,14 +3695,16 @@ png_do_expand(png_row_infop row_info, png_bytep row, *dp-- = *sp--; } } + else if (row_info->bit_depth == 16) { + png_byte gray_high = (gray >> 8) & 0xff; + png_byte gray_low = gray & 0xff; sp = row + row_info->rowbytes - 1; dp = row + (row_info->rowbytes << 1) - 1; - for (i = 0; i < row_info->width; i++) + for (i = 0; i < row_width; i++) { - if (((png_uint_16)*(sp) | - ((png_uint_16)*(sp - 1) << 8)) == gray) + if (*(sp - 1) == gray_high && *(sp) == gray_low) { *dp-- = 0; *dp-- = 0; @@ -3051,24 +3718,26 @@ png_do_expand(png_row_infop row_info, png_bytep row, *dp-- = *sp--; } } + row_info->color_type = PNG_COLOR_TYPE_GRAY_ALPHA; row_info->channels = 2; row_info->pixel_depth = (png_byte)(row_info->bit_depth << 1); - row_info->rowbytes = - ((row_info->width * row_info->pixel_depth) >> 3); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, + row_width); } } else if (row_info->color_type == PNG_COLOR_TYPE_RGB && trans_value) { if (row_info->bit_depth == 8) { + png_byte red = trans_value->red & 0xff; + png_byte green = trans_value->green & 0xff; + png_byte blue = trans_value->blue & 0xff; sp = row + (png_size_t)row_info->rowbytes - 1; - dp = row + (png_size_t)(row_info->width << 2) - 1; - for (i = 0; i < row_info->width; i++) + dp = row + (png_size_t)(row_width << 2) - 1; + for (i = 0; i < row_width; i++) { - if (*(sp - 2) == trans_value->red && - *(sp - 1) == trans_value->green && - *(sp - 0) == trans_value->blue) + if (*(sp - 2) == red && *(sp - 1) == green && *(sp) == blue) *dp-- = 0; else *dp-- = 0xff; @@ -3079,16 +3748,22 @@ png_do_expand(png_row_infop row_info, png_bytep row, } else if (row_info->bit_depth == 16) { + png_byte red_high = (trans_value->red >> 8) & 0xff; + png_byte green_high = (trans_value->green >> 8) & 0xff; + png_byte blue_high = (trans_value->blue >> 8) & 0xff; + png_byte red_low = trans_value->red & 0xff; + png_byte green_low = trans_value->green & 0xff; + png_byte blue_low = trans_value->blue & 0xff; sp = row + row_info->rowbytes - 1; - dp = row + (png_size_t)(row_info->width << 3) - 1; - for (i = 0; i < row_info->width; i++) + dp = row + (png_size_t)(row_width << 3) - 1; + for (i = 0; i < row_width; i++) { - if ((((png_uint_16)*(sp - 4) | - ((png_uint_16)*(sp - 5) << 8)) == trans_value->red) && - (((png_uint_16)*(sp - 2) | - ((png_uint_16)*(sp - 3) << 8)) == trans_value->green) && - (((png_uint_16)*(sp - 0) | - ((png_uint_16)*(sp - 1) << 8)) == trans_value->blue)) + if (*(sp - 5) == red_high && + *(sp - 4) == red_low && + *(sp - 3) == green_high && + *(sp - 2) == green_low && + *(sp - 1) == blue_high && + *(sp ) == blue_low) { *dp-- = 0; *dp-- = 0; @@ -3109,25 +3784,23 @@ png_do_expand(png_row_infop row_info, png_bytep row, row_info->color_type = PNG_COLOR_TYPE_RGB_ALPHA; row_info->channels = 4; row_info->pixel_depth = (png_byte)(row_info->bit_depth << 2); - row_info->rowbytes = - ((row_info->width * row_info->pixel_depth) >> 3); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); } } } #endif -#if defined(PNG_READ_DITHER_SUPPORTED) -void -png_do_dither(png_row_infop row_info, png_bytep row, - png_bytep palette_lookup, png_bytep dither_lookup) +#ifdef PNG_READ_QUANTIZE_SUPPORTED +void /* PRIVATE */ +png_do_quantize(png_row_infop row_info, png_bytep row, + png_bytep palette_lookup, png_bytep quantize_lookup) { png_bytep sp, dp; png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_quantize"); - png_debug(1, "in png_do_dither\n"); -#if defined(PNG_USELESS_TESTS_SUPPORTED) - if (row != NULL && row_info != NULL) -#endif { if (row_info->color_type == PNG_COLOR_TYPE_RGB && palette_lookup && row_info->bit_depth == 8) @@ -3135,35 +3808,34 @@ png_do_dither(png_row_infop row_info, png_bytep row, int r, g, b, p; sp = row; dp = row; - for (i = 0; i < row_info->width; i++) + for (i = 0; i < row_width; i++) { r = *sp++; g = *sp++; b = *sp++; - /* this looks real messy, but the compiler will reduce - it down to a reasonable formula. For example, with - 5 bits per color, we get: - p = (((r >> 3) & 0x1f) << 10) | - (((g >> 3) & 0x1f) << 5) | - ((b >> 3) & 0x1f); - */ - p = (((r >> (8 - PNG_DITHER_RED_BITS)) & - ((1 << PNG_DITHER_RED_BITS) - 1)) << - (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) | - (((g >> (8 - PNG_DITHER_GREEN_BITS)) & - ((1 << PNG_DITHER_GREEN_BITS) - 1)) << - (PNG_DITHER_BLUE_BITS)) | - ((b >> (8 - PNG_DITHER_BLUE_BITS)) & - ((1 << PNG_DITHER_BLUE_BITS) - 1)); + /* This looks real messy, but the compiler will reduce + * it down to a reasonable formula. For example, with + * 5 bits per color, we get: + * p = (((r >> 3) & 0x1f) << 10) | + * (((g >> 3) & 0x1f) << 5) | + * ((b >> 3) & 0x1f); + */ + p = (((r >> (8 - PNG_QUANTIZE_RED_BITS)) & + ((1 << PNG_QUANTIZE_RED_BITS) - 1)) << + (PNG_QUANTIZE_GREEN_BITS + PNG_QUANTIZE_BLUE_BITS)) | + (((g >> (8 - PNG_QUANTIZE_GREEN_BITS)) & + ((1 << PNG_QUANTIZE_GREEN_BITS) - 1)) << + (PNG_QUANTIZE_BLUE_BITS)) | + ((b >> (8 - PNG_QUANTIZE_BLUE_BITS)) & + ((1 << PNG_QUANTIZE_BLUE_BITS) - 1)); *dp++ = palette_lookup[p]; } row_info->color_type = PNG_COLOR_TYPE_PALETTE; row_info->channels = 1; row_info->pixel_depth = row_info->bit_depth; - row_info->rowbytes = - ((row_info->width * row_info->pixel_depth + 7) >> 3); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); } else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA && palette_lookup != NULL && row_info->bit_depth == 8) @@ -3171,239 +3843,361 @@ png_do_dither(png_row_infop row_info, png_bytep row, int r, g, b, p; sp = row; dp = row; - for (i = 0; i < row_info->width; i++) + for (i = 0; i < row_width; i++) { r = *sp++; g = *sp++; b = *sp++; sp++; - p = (((r >> (8 - PNG_DITHER_RED_BITS)) & - ((1 << PNG_DITHER_RED_BITS) - 1)) << - (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) | - (((g >> (8 - PNG_DITHER_GREEN_BITS)) & - ((1 << PNG_DITHER_GREEN_BITS) - 1)) << - (PNG_DITHER_BLUE_BITS)) | - ((b >> (8 - PNG_DITHER_BLUE_BITS)) & - ((1 << PNG_DITHER_BLUE_BITS) - 1)); + p = (((r >> (8 - PNG_QUANTIZE_RED_BITS)) & + ((1 << PNG_QUANTIZE_RED_BITS) - 1)) << + (PNG_QUANTIZE_GREEN_BITS + PNG_QUANTIZE_BLUE_BITS)) | + (((g >> (8 - PNG_QUANTIZE_GREEN_BITS)) & + ((1 << PNG_QUANTIZE_GREEN_BITS) - 1)) << + (PNG_QUANTIZE_BLUE_BITS)) | + ((b >> (8 - PNG_QUANTIZE_BLUE_BITS)) & + ((1 << PNG_QUANTIZE_BLUE_BITS) - 1)); *dp++ = palette_lookup[p]; } row_info->color_type = PNG_COLOR_TYPE_PALETTE; row_info->channels = 1; row_info->pixel_depth = row_info->bit_depth; - row_info->rowbytes = - ((row_info->width * row_info->pixel_depth + 7) >> 3); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); } else if (row_info->color_type == PNG_COLOR_TYPE_PALETTE && - dither_lookup && row_info->bit_depth == 8) + quantize_lookup && row_info->bit_depth == 8) { sp = row; - for (i = 0; i < row_info->width; i++, sp++) + for (i = 0; i < row_width; i++, sp++) { - *sp = dither_lookup[*sp]; + *sp = quantize_lookup[*sp]; } } } } #endif -#if defined(PNG_READ_GAMMA_SUPPORTED) -static int png_gamma_shift[] = - {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0}; +#ifdef PNG_FLOATING_POINT_SUPPORTED +#ifdef PNG_READ_GAMMA_SUPPORTED +static PNG_CONST int png_gamma_shift[] = + {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0, 0x00}; /* We build the 8- or 16-bit gamma tables here. Note that for 16-bit * tables, we don't make a full table if we are reducing to 8-bit in * the future. Note also how the gamma_16 tables are segmented so that * we don't need to allocate > 64K chunks for a full 16-bit table. + * + * See the PNG extensions document for an integer algorithm for creating + * the gamma tables. Maybe we will implement that here someday. + * + * We should only reach this point if + * + * the file_gamma is known (i.e., the gAMA or sRGB chunk is present, + * or the application has provided a file_gamma) + * + * AND + * { + * the screen_gamma is known + * + * OR + * + * RGB_to_gray transformation is being performed + * } + * + * AND + * { + * the screen_gamma is different from the reciprocal of the + * file_gamma by more than the specified threshold + * + * OR + * + * a background color has been specified and the file_gamma + * and screen_gamma are not 1.0, within the specified threshold. + * } */ -void -png_build_gamma_table(png_structp png_ptr) + +void /* PRIVATE */ +png_build_gamma_table(png_structp png_ptr, png_byte bit_depth) { - png_debug(1, "in png_build_gamma_table\n"); - if (png_ptr->bit_depth <= 8) - { - int i; - double g; + png_debug(1, "in png_build_gamma_table"); - g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); + if (bit_depth <= 8) + { + int i; + double g; - png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr, - (png_uint_32)256); + if (png_ptr->screen_gamma > .000001) + g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); - for (i = 0; i < 256; i++) - { - png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0, - g) * 255.0 + .5); - } + else + g = 1.0; -#if defined(PNG_READ_BACKGROUND_SUPPORTED) - if (png_ptr->transformations & PNG_BACKGROUND) - { - g = 1.0 / (png_ptr->gamma); + png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr, + (png_uint_32)256); - png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr, - (png_uint_32)256); + for (i = 0; i < 256; i++) + { + png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0, + g) * 255.0 + .5); + } - for (i = 0; i < 256; i++) - { - png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0, - g) * 255.0 + .5); - } +#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ + defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) + if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY)) + { - g = 1.0 / (png_ptr->screen_gamma); + g = 1.0 / (png_ptr->gamma); - png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr, - (png_uint_32)256); + png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr, + (png_uint_32)256); - for (i = 0; i < 256; i++) - { - png_ptr->gamma_from_1[i] = (png_byte)(pow((double)i / 255.0, - g) * 255.0 + .5); - } - } -#endif /* PNG_BACKGROUND_SUPPORTED */ - } - else - { - double g; - int i, j, shift, num; - int sig_bit; - png_uint_32 ig; + for (i = 0; i < 256; i++) + { + png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0, + g) * 255.0 + .5); + } - if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) - { - sig_bit = (int)png_ptr->sig_bit.red; - if ((int)png_ptr->sig_bit.green > sig_bit) - sig_bit = png_ptr->sig_bit.green; - if ((int)png_ptr->sig_bit.blue > sig_bit) - sig_bit = png_ptr->sig_bit.blue; - } - else - { - sig_bit = (int)png_ptr->sig_bit.gray; - } - if (sig_bit > 0) - shift = 16 - sig_bit; - else - shift = 0; + png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr, + (png_uint_32)256); - if (png_ptr->transformations & PNG_16_TO_8) - { - if (shift < (16 - PNG_MAX_GAMMA_8)) - shift = (16 - PNG_MAX_GAMMA_8); - } + if (png_ptr->screen_gamma > 0.000001) + g = 1.0 / png_ptr->screen_gamma; + + else + g = png_ptr->gamma; /* Probably doing rgb_to_gray */ + + for (i = 0; i < 256; i++) + { + png_ptr->gamma_from_1[i] = (png_byte)(pow((double)i / 255.0, + g) * 255.0 + .5); + + } + } +#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */ + } + else + { + double g; + int i, j, shift, num; + int sig_bit; + png_uint_32 ig; + + if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) + { + sig_bit = (int)png_ptr->sig_bit.red; + + if ((int)png_ptr->sig_bit.green > sig_bit) + sig_bit = png_ptr->sig_bit.green; + + if ((int)png_ptr->sig_bit.blue > sig_bit) + sig_bit = png_ptr->sig_bit.blue; + } + else + { + sig_bit = (int)png_ptr->sig_bit.gray; + } + + if (sig_bit > 0) + shift = 16 - sig_bit; + + else + shift = 0; + + if (png_ptr->transformations & PNG_16_TO_8) + { + if (shift < (16 - PNG_MAX_GAMMA_8)) + shift = (16 - PNG_MAX_GAMMA_8); + } + + if (shift > 8) + shift = 8; + + if (shift < 0) + shift = 0; + + png_ptr->gamma_shift = (png_byte)shift; + + num = (1 << (8 - shift)); + + if (png_ptr->screen_gamma > .000001) + g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); + else + g = 1.0; + + png_ptr->gamma_16_table = (png_uint_16pp)png_calloc(png_ptr, + (png_uint_32)(num * png_sizeof(png_uint_16p))); + + if (png_ptr->transformations & (PNG_16_TO_8 | PNG_BACKGROUND)) + { + double fin, fout; + png_uint_32 last, max; + + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); + } + + g = 1.0 / g; + last = 0; + for (i = 0; i < 256; i++) + { + fout = ((double)i + 0.5) / 256.0; + fin = pow(fout, g); + max = (png_uint_32)(fin * (double)((png_uint_32)num << 8)); + while (last <= max) + { + png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] + [(int)(last >> (8 - shift))] = (png_uint_16)( + (png_uint_16)i | ((png_uint_16)i << 8)); + last++; + } + } + while (last < ((png_uint_32)num << 8)) + { + png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] + [(int)(last >> (8 - shift))] = (png_uint_16)65535L; + last++; + } + } + else + { + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); - if (shift > 8) - shift = 8; - if (shift < 0) - shift = 0; + ig = (((png_uint_32)i * (png_uint_32)png_gamma_shift[shift]) >> 4); - png_ptr->gamma_shift = (png_byte)shift; + for (j = 0; j < 256; j++) + { + png_ptr->gamma_16_table[i][j] = + (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / + 65535.0, g) * 65535.0 + .5); + } + } + } - num = (1 << (8 - shift)); +#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ + defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) + if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY)) + { - g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); + g = 1.0 / (png_ptr->gamma); - png_ptr->gamma_16_table = (png_uint_16pp)png_malloc(png_ptr, - (png_uint_32)(num * sizeof (png_uint_16p))); + png_ptr->gamma_16_to_1 = (png_uint_16pp)png_calloc(png_ptr, + (png_uint_32)(num * png_sizeof(png_uint_16p ))); - if ((png_ptr->transformations & PNG_16_TO_8) && - !(png_ptr->transformations & PNG_BACKGROUND)) - { - double fin, fout; - png_uint_32 last, max; + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); - for (i = 0; i < num; i++) - { - png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, - (png_uint_32)(256 * sizeof (png_uint_16))); - } + ig = (((png_uint_32)i * + (png_uint_32)png_gamma_shift[shift]) >> 4); + for (j = 0; j < 256; j++) + { + png_ptr->gamma_16_to_1[i][j] = + (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / + 65535.0, g) * 65535.0 + .5); + } + } - g = 1.0 / g; - last = 0; - for (i = 0; i < 256; i++) - { - fout = ((double)i + 0.5) / 256.0; - fin = pow(fout, g); - max = (png_uint_32)(fin * (double)((png_uint_32)num << 8)); - while (last <= max) - { - png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] - [(int)(last >> (8 - shift))] = (png_uint_16)( - (png_uint_16)i | ((png_uint_16)i << 8)); - last++; - } - } - while (last < ((png_uint_32)num << 8)) - { - png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] - [(int)(last >> (8 - shift))] = (png_uint_16)65535L; - last++; - } - } - else - { - for (i = 0; i < num; i++) - { - png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, - (png_uint_32)(256 * sizeof (png_uint_16))); + if (png_ptr->screen_gamma > 0.000001) + g = 1.0 / png_ptr->screen_gamma; - ig = (((png_uint_32)i * (png_uint_32)png_gamma_shift[shift]) >> 4); - for (j = 0; j < 256; j++) - { - png_ptr->gamma_16_table[i][j] = - (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / - 65535.0, g) * 65535.0 + .5); - } - } - } + else + g = png_ptr->gamma; /* Probably doing rgb_to_gray */ -#if defined(PNG_READ_BACKGROUND_SUPPORTED) - if (png_ptr->transformations & PNG_BACKGROUND) + png_ptr->gamma_16_from_1 = (png_uint_16pp)png_calloc(png_ptr, + (png_uint_32)(num * png_sizeof(png_uint_16p))); + + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); + + ig = (((png_uint_32)i * + (png_uint_32)png_gamma_shift[shift]) >> 4); + + for (j = 0; j < 256; j++) + { + png_ptr->gamma_16_from_1[i][j] = + (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / + 65535.0, g) * 65535.0 + .5); + } + } + } +#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */ + } +} +#endif +/* To do: install integer version of png_build_gamma_table here */ +#endif + +#ifdef PNG_MNG_FEATURES_SUPPORTED +/* Undoes intrapixel differencing */ +void /* PRIVATE */ +png_do_read_intrapixel(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_read_intrapixel"); + + if ( + (row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + int bytes_per_pixel; + png_uint_32 row_width = row_info->width; + if (row_info->bit_depth == 8) { - g = 1.0 / (png_ptr->gamma); + png_bytep rp; + png_uint_32 i; - png_ptr->gamma_16_to_1 = (png_uint_16pp)png_malloc(png_ptr, - (png_uint_32)(num * sizeof (png_uint_16p ))); + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 3; - for (i = 0; i < num; i++) - { - png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr, - (png_uint_32)(256 * sizeof (png_uint_16))); + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 4; - ig = (((png_uint_32)i * - (png_uint_32)png_gamma_shift[shift]) >> 4); - for (j = 0; j < 256; j++) - { - png_ptr->gamma_16_to_1[i][j] = - (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / - 65535.0, g) * 65535.0 + .5); - } + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + *(rp) = (png_byte)((256 + *rp + *(rp+1))&0xff); + *(rp+2) = (png_byte)((256 + *(rp+2) + *(rp+1))&0xff); } - g = 1.0 / (png_ptr->screen_gamma); + } + else if (row_info->bit_depth == 16) + { + png_bytep rp; + png_uint_32 i; - png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr, - (png_uint_32)(num * sizeof (png_uint_16p))); + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 6; - for (i = 0; i < num; i++) - { - png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr, - (png_uint_32)(256 * sizeof (png_uint_16))); + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 8; - ig = (((png_uint_32)i * - (png_uint_32)png_gamma_shift[shift]) >> 4); - for (j = 0; j < 256; j++) - { - png_ptr->gamma_16_from_1[i][j] = - (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / - 65535.0, g) * 65535.0 + .5); - } + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + png_uint_32 s0 = (*(rp ) << 8) | *(rp + 1); + png_uint_32 s1 = (*(rp + 2) << 8) | *(rp + 3); + png_uint_32 s2 = (*(rp + 4) << 8) | *(rp + 5); + png_uint_32 red = (png_uint_32)((s0 + s1 + 65536L) & 0xffffL); + png_uint_32 blue = (png_uint_32)((s2 + s1 + 65536L) & 0xffffL); + *(rp ) = (png_byte)((red >> 8) & 0xff); + *(rp+1) = (png_byte)(red & 0xff); + *(rp+4) = (png_byte)((blue >> 8) & 0xff); + *(rp+5) = (png_byte)(blue & 0xff); } } -#endif /* PNG_BACKGROUND_SUPPORTED */ } } -#endif - +#endif /* PNG_MNG_FEATURES_SUPPORTED */ +#endif /* PNG_READ_SUPPORTED */