/* pngrtran.c - transforms the data in a row for PNG readers
*
- * libpng 1.0.1
+ * Last changed in libpng 1.2.30 [August 15, 2008]
* 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
+ * Copyright (c) 1998-2008 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 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
#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 */
-
+#if defined(PNG_READ_SUPPORTED)
/* 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");
/* Tell libpng how we react to CRC errors in critical chunks */
+ if (png_ptr == NULL) return;
switch (crit_action)
{
case PNG_CRC_NO_CHANGE: /* leave setting as is */
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.");
+ png_warning(png_ptr,
+ "Can't discard critical data on CRC error.");
case PNG_CRC_ERROR_QUIT: /* error/quit */
case PNG_CRC_DEFAULT:
default:
}
}
-#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
+ defined(PNG_FLOATING_POINT_SUPPORTED)
/* handle alpha and tRNS via a background color */
-void
+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");
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);
#if defined(PNG_READ_16_TO_8_SUPPORTED)
/* strip 16 bit depth files to 8 bit depth */
-void
+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
+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
typedef png_dsort FAR * png_dsortp;
typedef png_dsort FAR * FAR * png_dsortpp;
-void
+void PNGAPI
png_set_dither(png_structp png_ptr, png_colorp palette,
int num_palette, int maximum_colors, png_uint_16p histogram,
int full_dither)
{
- png_debug(1, "in png_set_dither\n");
+ png_debug(1, "in png_set_dither");
+ if (png_ptr == NULL) return;
png_ptr->transformations |= PNG_DITHER;
if (!full_dither)
int i;
png_ptr->dither_index = (png_bytep)png_malloc(png_ptr,
- (png_uint_32)(num_palette * sizeof (png_byte)));
+ (png_uint_32)(num_palette * png_sizeof(png_byte)));
for (i = 0; i < num_palette; i++)
png_ptr->dither_index[i] = (png_byte)i;
}
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)));
+ png_ptr->dither_sort = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)(num_palette * png_sizeof(png_byte)));
- /* initialize the sort array */
+ /* initialize the dither_sort array */
for (i = 0; i < num_palette; i++)
- sort[i] = (png_byte)i;
+ png_ptr->dither_sort[i] = (png_byte)i;
/* Find the least used palette entries by starting a
bubble sort, and running it until we have sorted
done = 1;
for (j = 0; j < i; j++)
{
- if (histogram[sort[j]] < histogram[sort[j + 1]])
+ if (histogram[png_ptr->dither_sort[j]]
+ < histogram[png_ptr->dither_sort[j + 1]])
{
png_byte t;
- t = sort[j];
- sort[j] = sort[j + 1];
- sort[j + 1] = t;
+ t = png_ptr->dither_sort[j];
+ png_ptr->dither_sort[j] = png_ptr->dither_sort[j + 1];
+ png_ptr->dither_sort[j + 1] = t;
done = 0;
}
}
/* swap the palette around, and set up a table, if necessary */
if (full_dither)
{
- 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++)
+ for (i = 0; i < maximum_colors; i++)
{
- if ((int)sort[i] >= maximum_colors)
+ if ((int)png_ptr->dither_sort[i] >= maximum_colors)
{
do
j--;
- while ((int)sort[j] >= maximum_colors);
+ while ((int)png_ptr->dither_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++)
+ for (i = 0; i < maximum_colors; i++)
{
/* only move the colors we need to */
- if ((int)sort[i] >= maximum_colors)
+ if ((int)png_ptr->dither_sort[i] >= maximum_colors)
{
png_color tmp_color;
do
j--;
- while ((int)sort[j] >= maximum_colors);
+ while ((int)png_ptr->dither_sort[j] >= maximum_colors);
tmp_color = palette[j];
palette[j] = palette[i];
}
}
}
- png_free(png_ptr, sort);
+ png_free(png_ptr, png_ptr->dither_sort);
+ png_ptr->dither_sort = NULL;
}
else
{
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 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 */
+
+ t = NULL;
/* 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)));
+ 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)));
+ hash = (png_dsortpp)png_malloc(png_ptr, (png_uint_32)(769 *
+ png_sizeof(png_dsortp)));
for (i = 0; i < 769; i++)
hash[i] = NULL;
-/* png_memset(hash, 0, 769 * sizeof (png_dsortp)); */
+/* png_memset(hash, 0, 769 * png_sizeof(png_dsortp)); */
num_new_palette = num_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)
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;
}
num_new_palette--;
- palette[index_to_palette[j]] = palette[num_new_palette];
+ palette[png_ptr->index_to_palette[j]]
+ = palette[num_new_palette];
if (!full_dither)
{
int k;
for (k = 0; k < num_palette; k++)
{
if (png_ptr->dither_index[k] ==
- index_to_palette[j])
+ png_ptr->index_to_palette[j])
png_ptr->dither_index[k] =
- index_to_palette[next_j];
+ png_ptr->index_to_palette[next_j];
if ((int)png_ptr->dither_index[k] ==
num_new_palette)
png_ptr->dither_index[k] =
- index_to_palette[j];
+ 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;
{
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;
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;
}
if (full_dither)
{
int i;
- int total_bits, num_red, num_green, num_blue;
- png_size_t num_entries;
png_bytep distance;
-
- total_bits = PNG_DITHER_RED_BITS + PNG_DITHER_GREEN_BITS +
+ int 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);
+ int num_red = (1 << PNG_DITHER_RED_BITS);
+ int num_green = (1 << PNG_DITHER_GREEN_BITS);
+ int num_blue = (1 << PNG_DITHER_BLUE_BITS);
+ png_size_t 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_uint_32)(num_entries * png_sizeof(png_byte)));
- png_memset(png_ptr->palette_lookup, 0, num_entries * sizeof (png_byte));
+ png_memset(png_ptr->palette_lookup, 0, num_entries *
+ png_sizeof(png_byte));
distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries *
- sizeof(png_byte)));
+ png_sizeof(png_byte)));
- png_memset(distance, 0xff, num_entries * 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_DITHER_RED_BITS));
+ int g = (palette[i].green >> (8 - PNG_DITHER_GREEN_BITS));
+ int b = (palette[i].blue >> (8 - PNG_DITHER_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_DITHER_BLUE_BITS + PNG_DITHER_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_DITHER_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])
{
}
#endif
-#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
+/* 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-1.4.0, png_set_gray_1_2_4_to_8() was modified
+ * to expand only the sample depth but not to expand the tRNS to alpha.
+ */
+
+/* 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;
+}
+
+#if !defined(PNG_1_0_X)
+/* 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_1_0_X) || defined(PNG_1_2_X)
+/* Expand grayscale images of less than 8-bit depth to 8 bits. */
+/* Deprecated as of libpng-1.2.9 */
+void PNGAPI
+png_set_gray_1_2_4_to_8(png_structp png_ptr)
+{
+ png_debug(1, "in png_set_gray_1_2_4_to_8");
+ if (png_ptr == NULL) return;
+ png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
+}
+#endif
+
+
+/* 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) */
+
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
-void
+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.)
+#if defined(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)
{
- 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.");
+ 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
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
-void
+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");
+ 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)
+#if defined(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) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_LEGACY_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;
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
png_ptr->transformations |= PNG_USER_TRANSFORM;
png_ptr->read_user_transform_fn = read_user_transform_fn;
+#endif
+#ifdef PNG_LEGACY_SUPPORTED
+ if (read_user_transform_fn)
+ png_warning(png_ptr,
+ "This version of libpng does not support user transforms");
+#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\n");
- color_type = png_ptr->color_type;
+ png_debug(1, "in png_init_read_transformations");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ if (png_ptr != NULL)
+#endif
+ {
+#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)
+
+#if defined(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)
{
- if (color_type == PNG_COLOR_TYPE_GRAY)
+ 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_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_values.gray *= (png_uint_16)0xff;
+ png_ptr->trans_values.red = png_ptr->trans_values.green
+ = png_ptr->trans_values.blue = png_ptr->trans_values.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_values.gray *= (png_uint_16)0x55;
+ png_ptr->trans_values.red = png_ptr->trans_values.green
+ = png_ptr->trans_values.blue = png_ptr->trans_values.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_values.gray *= (png_uint_16)0x11;
+ png_ptr->trans_values.red = png_ptr->trans_values.green
+ = png_ptr->trans_values.blue = png_ptr->trans_values.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;
}
}
if (png_ptr->transformations & PNG_INVERT_ALPHA)
{
#if defined(PNG_READ_EXPAND_SUPPORTED)
- if (!(png_ptr->transformations & PNG_EXPAND))
+ if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
#endif
{
- /* invert the alpha channel (in tRNS) unless the pixels are
+ /* 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];
+ int i, istop;
+ istop=(int)png_ptr->num_trans;
+ for (i=0; i<istop; i++)
+ png_ptr->trans[i] = (png_byte)(255 - png_ptr->trans[i]);
}
}
#endif
}
#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; i<png_ptr->num_trans; i++)
+ {
+ if (png_ptr->trans[i] != 0 && png_ptr->trans[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)
{
if (color_type == PNG_COLOR_TYPE_PALETTE)
{
- int num_palette, i;
+ /* could skip if no transparency and
+ */
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];
back_1.blue = (png_byte)(pow(
(double)png_ptr->background.blue/255, g) * 255.0 + .5);
}
-
for (i = 0; i < num_palette; i++)
{
if (i < (int)png_ptr->num_trans && png_ptr->trans[i] != 0xff)
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)
{
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(
}
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
+#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++)
{
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)
else
#endif
-#endif
+#endif /* PNG_READ_GAMMA_SUPPORTED && PNG_FLOATING_POINT_SUPPORTED */
#if defined(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)
{
}
else if (png_ptr->trans[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_composite(palette[i].green, palette[i].green,
png_ptr->trans[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)
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
}
* 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");
+ png_debug(1, "in png_read_transform_info");
#if defined(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;
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 0 /* Removed from libpng-1.2.27 */
+ else
+ info_ptr->color_type |= PNG_COLOR_MASK_COLOR;
+#endif
+ }
if (info_ptr->bit_depth < 8)
info_ptr->bit_depth = 8;
info_ptr->num_trans = 0;
}
#endif
+#if defined(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
+
#if defined(PNG_READ_16_TO_8_SUPPORTED)
- if ((png_ptr->transformations & PNG_16_TO_8) && info_ptr->bit_depth == 16)
+ if ((png_ptr->transformations & PNG_16_TO_8) && (info_ptr->bit_depth == 16))
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 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & PNG_RGB_TO_GRAY)
+ info_ptr->color_type &= ~PNG_COLOR_MASK_COLOR;
+#endif
+
#if defined(PNG_READ_DITHER_SUPPORTED)
if (png_ptr->transformations & PNG_DITHER)
{
#endif
#if defined(PNG_READ_PACK_SUPPORTED)
- if ((png_ptr->transformations & PNG_PACK) && info_ptr->bit_depth < 8)
+ 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)
info_ptr->channels = 1;
#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
- if (png_ptr->transformations & PNG_STRIP_ALPHA)
+ if (png_ptr->flags & PNG_FLAG_STRIP_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_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 !defined(PNG_1_0_X)
+ if (png_ptr->transformations & PNG_ADD_ALPHA)
+ info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
+#endif
}
#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);
+
+#if !defined(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)
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
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)
png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1,
png_ptr->palette, png_ptr->trans, 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));
else
#endif
#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
- if (png_ptr->transformations & PNG_STRIP_ALPHA)
+ 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
+
+#if defined(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.
+ */
+
+#if defined(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)
((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_values), &(png_ptr->background)
+#if defined(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)
if ((png_ptr->transformations & PNG_GAMMA) &&
- !(png_ptr->transformations & PNG_BACKGROUND) &&
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ !((png_ptr->transformations & PNG_BACKGROUND) &&
+ ((png_ptr->num_trans != 0) ||
+ (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) &&
+#endif
(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_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);
-#endif
-
#if defined(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);
{
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)
+ if (png_ptr->row_info.rowbytes == (png_uint_32)0)
png_error(png_ptr, "png_do_dither returned rowbytes=0");
}
#endif
#endif
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
- if (png_ptr->transformations & PNG_GRAY_TO_RGB)
+ /* 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_USER_TRANSFORM_SUPPORTED)
if (png_ptr->transformations & PNG_USER_TRANSFORM)
- if(png_ptr->read_user_transform_fn != NULL)
+ {
+ 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_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 defined(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
}
* 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");
+ png_debug(1, "in png_do_unpack");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if (row != NULL && row_info != NULL && row_info->bit_depth < 8)
#else
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;
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;
}
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;
}
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
* 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 &&
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;
shift[channels++] = row_info->bit_depth - sig_bits->alpha;
}
- value = 0;
-
for (c = 0; c < channels; c++)
{
if (shift[c] <= 0)
{
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;
}
#if defined(PNG_READ_16_TO_8_SUPPORTED)
/* chop rows of bit depth 16 down to 8 */
-void
+void /* PRIVATE */
png_do_chop(png_row_infop row_info, png_bytep row)
{
- png_debug(1, "in png_do_chop\n");
+ png_debug(1, "in png_do_chop");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if (row != NULL && row_info != NULL && row_info->bit_depth == 16)
#else
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<istop; i++, sp += 2, dp++)
{
#if defined(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;
+ /* 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:
+ */
- * 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
}
#endif
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
-void
+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");
+ png_debug(1, "in png_do_read_swap_alpha");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if (row != NULL && row_info != NULL)
#endif
{
+ 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);
/* 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);
/* 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);
/* 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);
#endif
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
-void
+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");
+ png_debug(1, "in png_do_read_invert_alpha");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if (row != NULL && row_info != NULL)
#endif
{
+ 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;
}
}
}
/* 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;
}
}
}
#if defined(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_debug(1, "in png_do_read_filler\n");
+ 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");
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
+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\n");
+ png_debug(1, "in png_do_gray_to_rgb");
if (row_info->bit_depth >= 8 &&
#if defined(PNG_USELESS_TESTS_SUPPORTED)
row != NULL && row_info != NULL &&
{
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--);
+ }
+ }
+ else
+ {
+ 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;
- sp--;
+ *(dp--) = *(sp - 1);
+ *(dp--) = *(sp--);
+ *(dp--) = *(sp--);
+ }
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ 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--);
+ }
+ }
+ else
+ {
+ 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--);
+ *(dp--) = *sp;
+ *(dp--) = *(sp - 1);
+ *(dp--) = *sp;
+ *(dp--) = *(sp - 1);
+ *(dp--) = *(sp--);
+ *(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);
+ }
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+/* reduce RGB files to grayscale, with or without alpha
+ * using the equation given in Poynton's ColorFAQ at
+ * <http://www.inforamp.net/~poynton/> (THIS LINK IS DEAD June 2008)
+ * New link:
+ * <http://www.poynton.com/notes/colour_and_gamma/>
+ * 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 (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ (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
+
+ else /* RGB bit_depth == 16 */
{
- 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++)
+#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)
{
- *(dp--) = *sp;
- *(dp--) = *(sp - 1);
- *(dp--) = *sp;
- *(dp--) = *(sp - 1);
- *(dp--) = *sp;
- *(dp--) = *(sp - 1);
- sp--;
- sp--;
+ 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);
+ }
}
}
}
- else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
{
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++)
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL)
{
- *(dp--) = *(sp--);
- *(dp--) = *sp;
- *(dp--) = *sp;
- *(dp--) = *sp;
- sp--;
+ 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
+ else /* RGBA bit_depth == 16 */
{
- 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++)
+#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)
{
- *(dp--) = *(sp--);
- *(dp--) = *(sp--);
- *(dp--) = *sp;
- *(dp--) = *(sp - 1);
- *(dp--) = *sp;
- *(dp--) = *(sp - 1);
- *(dp--) = *sp;
- *(dp--) = *(sp - 1);
- sp--;
- sp--;
+ 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->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 = ((row_info->width *
- row_info->pixel_depth + 7) >> 3);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
}
+ return rgb_error;
}
#endif
* 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;
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;
/* This function is currently unused. Do we really need it? */
#if defined(PNG_READ_DITHER_SUPPORTED) && defined(PNG_CORRECT_PALETTE_SUPPORTED)
-void
+void /* PRIVATE */
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_debug(1, "in png_correct_palette");
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
+ defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+ if (png_ptr->transformations & (PNG_GAMMA | PNG_BACKGROUND))
{
png_color back, back_1;
* "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_values, png_color_16p background
+#if defined(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 &&
{
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)
+ if ((png_uint_16)((*sp >> shift) & 0x01)
== trans_values->gray)
{
*sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
}
case 2:
{
- sp = row;
- shift = 6;
- for (i = 0; i < row_info->width; i++)
+#if defined(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_values->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_values->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++)
+#if defined(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_values->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_values->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;
}
#if defined(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)
{
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 defined(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);
+ v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
if (v == trans_values->gray)
{
/* background is already in screen gamma */
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);
+ v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
if (v == trans_values->gray)
{
*sp = (png_byte)((background->gray >> 8) & 0xff);
#if defined(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 &&
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 &&
#if defined(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);
+ 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_values->red && g == trans_values->green &&
b == trans_values->blue)
{
}
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)];
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 (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
#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;
}
+#if defined(PNG_READ_GAMMA_SUPPORTED)
else if (a == 0)
{
*dp = (png_byte)background->gray;
{
png_composite(*dp, *sp, a, background_1->gray);
}
+#else
+ *dp = (png_byte)background->gray;
+#endif
}
}
}
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;
*dp = (png_byte)((v >> 8) & 0xff);
*(dp + 1) = (png_byte)(v & 0xff);
}
+#if defined(PNG_READ_GAMMA_SUPPORTED)
else if (a == 0)
+#else
+ else
+#endif
{
/* background is already in screen gamma */
*dp = (png_byte)((background->gray >> 8) & 0xff);
*(dp + 1) = (png_byte)(background->gray & 0xff);
}
+#if defined(PNG_READ_GAMMA_SUPPORTED)
else
{
png_uint_16 g, v, w;
*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);
}
+#if defined(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);
}
+#if defined(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
}
}
}
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];
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;
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;
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);
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);
}
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);
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);
}
}
}
#if defined(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\n");
+ png_debug(1, "in png_do_gamma");
if (
#if defined(PNG_USELESS_TESTS_SUPPORTED)
row != NULL && row_info != NULL &&
{
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;
{
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;
{
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;
}
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;
{
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)|
+ *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) );
+ ((((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;
#endif
#if defined(PNG_READ_EXPAND_SUPPORTED)
-/* Expands a palette row to an rgb or rgba row depending
+/* 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)
{
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\n");
+ png_debug(1, "in png_do_expand_palette");
if (
#if defined(PNG_USELESS_TESTS_SUPPORTED)
row != NULL && row_info != NULL &&
{
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;
}
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)
{
}
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)
{
}
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)
{
{
if (trans != 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;
}
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;
}
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;
}
}
}
-/* 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\n");
+ png_debug(1, "in png_do_expand");
#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)
{
{
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;
}
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)
}
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)
{
}
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;
}
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;
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;
}
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;
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
+void /* PRIVATE */
png_do_dither(png_row_infop row_info, png_bytep row,
png_bytep palette_lookup, png_bytep dither_lookup)
{
png_bytep sp, dp;
png_uint_32 i;
+ png_uint_32 row_width=row_info->width;
- png_debug(1, "in png_do_dither\n");
+ png_debug(1, "in png_do_dither");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if (row != NULL && row_info != NULL)
#endif
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++;
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)
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++;
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)
{
sp = row;
- for (i = 0; i < row_info->width; i++, sp++)
+ for (i = 0; i < row_width; i++, sp++)
{
*sp = dither_lookup[*sp];
}
}
#endif
+#ifdef PNG_FLOATING_POINT_SUPPORTED
#if defined(PNG_READ_GAMMA_SUPPORTED)
-static int png_gamma_shift[] =
- {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0};
+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.
*/
-void
+void /* PRIVATE */
png_build_gamma_table(png_structp png_ptr)
{
- 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 (png_ptr->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);
+ else
+ g = 1.0;
- for (i = 0; i < 256; i++)
- {
- png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0,
- g) * 255.0 + .5);
- }
+ png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)256);
-#if defined(PNG_READ_BACKGROUND_SUPPORTED)
- if (png_ptr->transformations & PNG_BACKGROUND)
- {
- g = 1.0 / (png_ptr->gamma);
+ for (i = 0; i < 256; i++)
+ {
+ png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0,
+ g) * 255.0 + .5);
+ }
- png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr,
- (png_uint_32)256);
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+ defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY))
+ {
- for (i = 0; i < 256; i++)
- {
- png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0,
- g) * 255.0 + .5);
- }
+ g = 1.0 / (png_ptr->gamma);
- g = 1.0 / (png_ptr->screen_gamma);
+ png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)256);
- png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr,
- (png_uint_32)256);
+ for (i = 0; i < 256; i++)
+ {
+ png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0,
+ g) * 255.0 + .5);
+ }
- 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;
- 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;
- }
+ png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)256);
- if (sig_bit > 0)
- shift = 16 - sig_bit;
- else
- shift = 0;
+ if (png_ptr->screen_gamma > 0.000001)
+ g = 1.0 / png_ptr->screen_gamma;
+ else
+ g = png_ptr->gamma; /* probably doing rgb_to_gray */
- if (png_ptr->transformations & PNG_16_TO_8)
- {
- if (shift < (16 - PNG_MAX_GAMMA_8))
- shift = (16 - PNG_MAX_GAMMA_8);
- }
+ 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_malloc(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)));
+ }
- if (shift > 8)
- shift = 8;
- if (shift < 0)
- shift = 0;
+ 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)));
- png_ptr->gamma_shift = (png_byte)shift;
+ 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);
+ }
+ }
+ }
- 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_malloc(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;
+ else
+ g = png_ptr->gamma; /* probably doing rgb_to_gray */
- 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);
- }
- }
- }
+ png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr,
+ (png_uint_32)(num * png_sizeof(png_uint_16p)));
-#if defined(PNG_READ_BACKGROUND_SUPPORTED)
- if (png_ptr->transformations & PNG_BACKGROUND)
+ 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
+
+#if defined(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 (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+ row != NULL && row_info != NULL &&
+#endif
+ (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;
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 4;
+ else
+ return;
- for (i = 0; i < num; i++)
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
{
- png_ptr->gamma_16_to_1[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);
- }
+ *(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;
+ else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ bytes_per_pixel = 8;
+ else
+ return;
- for (i = 0; i < num; i++)
+ for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
{
- png_ptr->gamma_16_from_1[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_from_1[i][j] =
- (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
- 65535.0, g) * 65535.0 + .5);
- }
+ 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 */
projects / wxWidgets.git / blobdiff