/* pngtrans.c - transforms the data in a row (used by both readers and writers)
*
- * libpng 1.0.1
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
- * Copyright (c) 1996, 1997 Andreas Dilger
- * Copyright (c) 1998, Glenn Randers-Pehrson
- * March 15, 1998
+ * Last changed in libpng 1.4.2 [April 29, 2010]
+ * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
*/
-#define PNG_INTERNAL
+#define PNG_NO_PEDANTIC_WARNINGS
#include "png.h"
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+#include "pngpriv.h"
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* turn on bgr to rgb mapping */
-void
+/* Turn on BGR-to-RGB mapping */
+void PNGAPI
png_set_bgr(png_structp png_ptr)
{
- png_debug(1, "in png_set_bgr\n");
+ png_debug(1, "in png_set_bgr");
+
+ if (png_ptr == NULL)
+ return;
png_ptr->transformations |= PNG_BGR;
}
#endif
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* turn on 16 bit byte swapping */
-void
+/* Turn on 16 bit byte swapping */
+void PNGAPI
png_set_swap(png_structp png_ptr)
{
- png_debug(1, "in png_set_swap\n");
+ png_debug(1, "in png_set_swap");
+
+ if (png_ptr == NULL)
+ return;
if (png_ptr->bit_depth == 16)
png_ptr->transformations |= PNG_SWAP_BYTES;
}
#endif
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-/* turn on pixel packing */
-void
+/* Turn on pixel packing */
+void PNGAPI
png_set_packing(png_structp png_ptr)
{
- png_debug(1, "in png_set_packing\n");
+ png_debug(1, "in png_set_packing");
+
+ if (png_ptr == NULL)
+ return;
if (png_ptr->bit_depth < 8)
{
png_ptr->transformations |= PNG_PACK;
#endif
#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-/* turn on packed pixel swapping */
-void
+/* Turn on packed pixel swapping */
+void PNGAPI
png_set_packswap(png_structp png_ptr)
{
- png_debug(1, "in png_set_packswap\n");
+ png_debug(1, "in png_set_packswap");
+
+ if (png_ptr == NULL)
+ return;
if (png_ptr->bit_depth < 8)
png_ptr->transformations |= PNG_PACKSWAP;
}
#endif
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
-void
+void PNGAPI
png_set_shift(png_structp png_ptr, png_color_8p true_bits)
{
- png_debug(1, "in png_set_shift\n");
+ png_debug(1, "in png_set_shift");
+
+ if (png_ptr == NULL)
+ return;
png_ptr->transformations |= PNG_SHIFT;
png_ptr->shift = *true_bits;
}
#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
defined(PNG_WRITE_INTERLACING_SUPPORTED)
-int
+int PNGAPI
png_set_interlace_handling(png_structp png_ptr)
{
- png_debug(1, "in png_set_interlace handling\n");
- if (png_ptr->interlaced)
+ png_debug(1, "in png_set_interlace handling");
+
+ if (png_ptr && png_ptr->interlaced)
{
png_ptr->transformations |= PNG_INTERLACE;
return (7);
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
/* Add a filler byte on read, or remove a filler or alpha byte on write.
* The filler type has changed in v0.95 to allow future 2-byte fillers
- * for 48-bit input data, as well as avoiding problems with some compilers
- * which don't like bytes as parameters.
+ * for 48-bit input data, as well as to avoid problems with some compilers
+ * that don't like bytes as parameters.
*/
-void
+void PNGAPI
png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc)
{
- png_debug(1, "in png_set_filler\n");
+ png_debug(1, "in png_set_filler");
+
+ if (png_ptr == NULL)
+ return;
png_ptr->transformations |= PNG_FILLER;
- png_ptr->filler = (png_byte)filler;
+ png_ptr->filler = (png_uint_16)filler;
if (filler_loc == PNG_FILLER_AFTER)
png_ptr->flags |= PNG_FLAG_FILLER_AFTER;
else
png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER;
- /* This should probably go in the "do_filler" routine */
- if (png_ptr->color_type == PNG_COLOR_TYPE_RGB && png_ptr->bit_depth == 8)
+ /* This should probably go in the "do_read_filler" routine.
+ * I attempted to do that in libpng-1.0.1a but that caused problems
+ * so I restored it in libpng-1.0.2a
+ */
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
{
png_ptr->usr_channels = 4;
}
+
+ /* Also I added this in libpng-1.0.2a (what happens when we expand
+ * a less-than-8-bit grayscale to GA? */
+
+ if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8)
+ {
+ png_ptr->usr_channels = 2;
+ }
+}
+
+/* Added to libpng-1.2.7 */
+void PNGAPI
+png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc)
+{
+ png_debug(1, "in png_set_add_alpha");
+
+ if (png_ptr == NULL)
+ return;
+ png_set_filler(png_ptr, filler, filler_loc);
+ png_ptr->transformations |= PNG_ADD_ALPHA;
}
+
#endif
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-void
+void PNGAPI
png_set_swap_alpha(png_structp png_ptr)
{
- png_debug(1, "in png_set_swap_alpha\n");
+ png_debug(1, "in png_set_swap_alpha");
+
+ if (png_ptr == NULL)
+ return;
png_ptr->transformations |= PNG_SWAP_ALPHA;
}
#endif
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-void
+void PNGAPI
png_set_invert_alpha(png_structp png_ptr)
{
- png_debug(1, "in png_set_invert_alpha\n");
+ png_debug(1, "in png_set_invert_alpha");
+
+ if (png_ptr == NULL)
+ return;
png_ptr->transformations |= PNG_INVERT_ALPHA;
}
#endif
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-void
+void PNGAPI
png_set_invert_mono(png_structp png_ptr)
{
- png_debug(1, "in png_set_invert_mono\n");
+ png_debug(1, "in png_set_invert_mono");
+
+ if (png_ptr == NULL)
+ return;
png_ptr->transformations |= PNG_INVERT_MONO;
}
-/* invert monocrome grayscale data */
-void
+/* Invert monochrome grayscale data */
+void /* PRIVATE */
png_do_invert(png_row_infop row_info, png_bytep row)
{
- png_debug(1, "in png_do_invert\n");
- if (row_info->bit_depth == 1 &&
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- row != NULL && row_info != NULL &&
-#endif
- row_info->color_type == PNG_COLOR_TYPE_GRAY)
+ png_debug(1, "in png_do_invert");
+
+ /* This test removed from libpng version 1.0.13 and 1.2.0:
+ * if (row_info->bit_depth == 1 &&
+ */
+ if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
+ {
+ png_bytep rp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+
+ for (i = 0; i < istop; i++)
+ {
+ *rp = (png_byte)(~(*rp));
+ rp++;
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+ row_info->bit_depth == 8)
{
- png_bytep rp;
+ png_bytep rp = row;
png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
- for (i = 0, rp = row; i < row_info->rowbytes; i++, rp++)
+ for (i = 0; i < istop; i+=2)
{
*rp = (png_byte)(~(*rp));
+ rp+=2;
+ }
+ }
+ else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+ row_info->bit_depth == 16)
+ {
+ png_bytep rp = row;
+ png_uint_32 i;
+ png_uint_32 istop = row_info->rowbytes;
+
+ for (i = 0; i < istop; i+=4)
+ {
+ *rp = (png_byte)(~(*rp));
+ *(rp+1) = (png_byte)(~(*(rp+1)));
+ rp+=4;
}
}
}
#endif
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* swaps byte order on 16 bit depth images */
-void
+/* Swaps byte order on 16 bit depth images */
+void /* PRIVATE */
png_do_swap(png_row_infop row_info, png_bytep row)
{
- png_debug(1, "in png_do_swap\n");
+ png_debug(1, "in png_do_swap");
+
if (
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- row != NULL && row_info != NULL &&
-#endif
row_info->bit_depth == 16)
{
- png_bytep rp;
- png_byte t;
+ png_bytep rp = row;
png_uint_32 i;
+ png_uint_32 istop= row_info->width * row_info->channels;
- for (i = 0, rp = row;
- i < row_info->width * row_info->channels;
- i++, rp += 2)
+ for (i = 0; i < istop; i++, rp += 2)
{
- t = *rp;
+ png_byte t = *rp;
*rp = *(rp + 1);
*(rp + 1) = t;
}
#endif
#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-static png_byte onebppswaptable[256] = {
+static PNG_CONST png_byte onebppswaptable[256] = {
0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
};
-static png_byte twobppswaptable[256] = {
+static PNG_CONST png_byte twobppswaptable[256] = {
0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0,
0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0,
0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4,
0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF
};
-static png_byte fourbppswaptable[256] = {
+static PNG_CONST png_byte fourbppswaptable[256] = {
0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70,
0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0,
0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71,
0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF
};
-/* swaps pixel packing order within bytes */
-void
+/* Swaps pixel packing order within bytes */
+void /* PRIVATE */
png_do_packswap(png_row_infop row_info, png_bytep row)
{
- png_debug(1, "in png_do_packswap\n");
+ png_debug(1, "in png_do_packswap");
+
if (
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- row != NULL && row_info != NULL &&
-#endif
row_info->bit_depth < 8)
{
png_bytep rp, end, table;
end = row + row_info->rowbytes;
if (row_info->bit_depth == 1)
- table = onebppswaptable;
+ table = (png_bytep)onebppswaptable;
else if (row_info->bit_depth == 2)
- table = twobppswaptable;
+ table = (png_bytep)twobppswaptable;
else if (row_info->bit_depth == 4)
- table = fourbppswaptable;
+ table = (png_bytep)fourbppswaptable;
else
return;
#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-/* remove filler or alpha byte(s) */
-void
+/* Remove filler or alpha byte(s) */
+void /* PRIVATE */
png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags)
{
- png_debug(1, "in png_do_strip_filler\n");
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- if (row != NULL && row_info != NULL)
-#endif
+ png_debug(1, "in png_do_strip_filler");
+
{
-/*
- if (row_info->color_type == PNG_COLOR_TYPE_RGB ||
- row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-*/
- if (row_info->channels == 4)
+ png_bytep sp=row;
+ png_bytep dp=row;
+ png_uint_32 row_width=row_info->width;
+ png_uint_32 i;
+
+ if ((row_info->color_type == PNG_COLOR_TYPE_RGB ||
+ (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
+ (flags & PNG_FLAG_STRIP_ALPHA))) &&
+ row_info->channels == 4)
{
if (row_info->bit_depth == 8)
{
/* This converts from RGBX or RGBA to RGB */
if (flags & PNG_FLAG_FILLER_AFTER)
{
- png_bytep sp, dp;
- png_uint_32 i;
-
- for (i = 1, sp = row + 4, dp = row + 3; i < row_info->width; i++)
+ dp+=3; sp+=4;
+ for (i = 1; i < row_width; i++)
{
*dp++ = *sp++;
*dp++ = *sp++;
/* This converts from XRGB or ARGB to RGB */
else
{
- png_bytep sp, dp;
- png_uint_32 i;
-
- for (i = 0, sp = row, dp = row; i < row_info->width; i++)
+ for (i = 0; i < row_width; i++)
{
sp++;
*dp++ = *sp++;
}
}
row_info->pixel_depth = 24;
- row_info->rowbytes = row_info->width * 3;
+ row_info->rowbytes = row_width * 3;
}
else /* if (row_info->bit_depth == 16) */
{
if (flags & PNG_FLAG_FILLER_AFTER)
{
- png_bytep sp, dp;
- png_uint_32 i;
-
/* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */
- for (i = 1, sp = row + 8, dp = row + 6; i < row_info->width; i++)
+ sp += 8; dp += 6;
+ for (i = 1; i < row_width; i++)
{
- /* This could be (although memcpy is probably slower):
+ /* This could be (although png_memcpy is probably slower):
png_memcpy(dp, sp, 6);
sp += 8;
dp += 6;
*/
+
*dp++ = *sp++;
*dp++ = *sp++;
*dp++ = *sp++;
}
else
{
- png_bytep sp, dp;
- png_uint_32 i;
-
/* This converts from XXRRGGBB or AARRGGBB to RRGGBB */
- for (i = 0, sp = row + 2, dp = row; i < row_info->width; i++)
+ for (i = 0; i < row_width; i++)
{
- /* This could be (although memcpy is probably slower):
+ /* This could be (although png_memcpy is probably slower):
png_memcpy(dp, sp, 6);
sp += 8;
dp += 6;
*/
+
+ sp+=2;
*dp++ = *sp++;
*dp++ = *sp++;
*dp++ = *sp++;
}
}
row_info->pixel_depth = 48;
- row_info->rowbytes = row_info->width * 6;
+ row_info->rowbytes = row_width * 6;
}
row_info->channels = 3;
}
-/*
- else if (row_info->color_type == PNG_COLOR_TYPE_GRAY ||
- row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-*/
- else if (row_info->channels == 2)
+ else if ((row_info->color_type == PNG_COLOR_TYPE_GRAY ||
+ (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+ (flags & PNG_FLAG_STRIP_ALPHA))) &&
+ row_info->channels == 2)
{
if (row_info->bit_depth == 8)
{
/* This converts from GX or GA to G */
if (flags & PNG_FLAG_FILLER_AFTER)
{
- png_bytep sp, dp;
- png_uint_32 i;
-
- for (i = 1, sp = row + 2, dp = row + 1; i < row_info->width; i++)
+ for (i = 0; i < row_width; i++)
{
*dp++ = *sp++;
sp++;
/* This converts from XG or AG to G */
else
{
- png_bytep sp, dp;
- png_uint_32 i;
-
- for (i = 0, sp = row, dp = row; i < row_info->width; i++)
+ for (i = 0; i < row_width; i++)
{
sp++;
*dp++ = *sp++;
}
}
row_info->pixel_depth = 8;
- row_info->rowbytes = row_info->width;
+ row_info->rowbytes = row_width;
}
else /* if (row_info->bit_depth == 16) */
{
if (flags & PNG_FLAG_FILLER_AFTER)
{
- png_bytep sp, dp;
- png_uint_32 i;
-
/* This converts from GGXX or GGAA to GG */
- for (i = 1, sp = row + 4, dp = row + 2; i < row_info->width; i++)
+ sp += 4; dp += 2;
+ for (i = 1; i < row_width; i++)
{
*dp++ = *sp++;
*dp++ = *sp++;
}
else
{
- png_bytep sp, dp;
- png_uint_32 i;
-
/* This converts from XXGG or AAGG to GG */
- for (i = 0, sp = row, dp = row; i < row_info->width; i++)
+ for (i = 0; i < row_width; i++)
{
sp += 2;
*dp++ = *sp++;
}
}
row_info->pixel_depth = 16;
- row_info->rowbytes = row_info->width * 2;
+ row_info->rowbytes = row_width * 2;
}
row_info->channels = 1;
}
+ if (flags & PNG_FLAG_STRIP_ALPHA)
+ row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
}
}
#endif
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* swaps red and blue bytes within a pixel */
-void
+/* Swaps red and blue bytes within a pixel */
+void /* PRIVATE */
png_do_bgr(png_row_infop row_info, png_bytep row)
{
- png_debug(1, "in png_do_bgr\n");
+ png_debug(1, "in png_do_bgr");
+
if (
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- row != NULL && row_info != NULL &&
-#endif
(row_info->color_type & PNG_COLOR_MASK_COLOR))
{
+ png_uint_32 row_width = row_info->width;
if (row_info->bit_depth == 8)
{
if (row_info->color_type == PNG_COLOR_TYPE_RGB)
{
png_bytep rp;
- png_byte save;
png_uint_32 i;
- for (i = 0, rp = row; i < row_info->width; i++, rp += 3)
+ for (i = 0, rp = row; i < row_width; i++, rp += 3)
{
- save = *rp;
+ png_byte save = *rp;
*rp = *(rp + 2);
*(rp + 2) = save;
}
else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
{
png_bytep rp;
- png_byte save;
png_uint_32 i;
- for (i = 0, rp = row; i < row_info->width; i++, rp += 4)
+ for (i = 0, rp = row; i < row_width; i++, rp += 4)
{
- save = *rp;
+ png_byte save = *rp;
*rp = *(rp + 2);
*(rp + 2) = save;
}
if (row_info->color_type == PNG_COLOR_TYPE_RGB)
{
png_bytep rp;
- png_byte save[2];
png_uint_32 i;
- for (i = 0, rp = row; i < row_info->width; i++, rp += 6)
+ for (i = 0, rp = row; i < row_width; i++, rp += 6)
{
- save[0] = *rp;
- save[1] = *(rp + 1);
+ png_byte save = *rp;
*rp = *(rp + 4);
+ *(rp + 4) = save;
+ save = *(rp + 1);
*(rp + 1) = *(rp + 5);
- *(rp + 4) = save[0];
- *(rp + 5) = save[1];
+ *(rp + 5) = save;
}
}
else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
{
png_bytep rp;
- png_byte save[2];
png_uint_32 i;
- for (i = 0, rp = row; i < row_info->width; i++, rp += 8)
+ for (i = 0, rp = row; i < row_width; i++, rp += 8)
{
- save[0] = *rp;
- save[1] = *(rp + 1);
+ png_byte save = *rp;
*rp = *(rp + 4);
+ *(rp + 4) = save;
+ save = *(rp + 1);
*(rp + 1) = *(rp + 5);
- *(rp + 4) = save[0];
- *(rp + 5) = save[1];
+ *(rp + 5) = save;
}
}
}
}
#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+void PNGAPI
+png_set_user_transform_info(png_structp png_ptr, png_voidp
+ user_transform_ptr, int user_transform_depth, int user_transform_channels)
+{
+ png_debug(1, "in png_set_user_transform_info");
+
+ if (png_ptr == NULL)
+ return;
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
+ png_ptr->user_transform_ptr = user_transform_ptr;
+ png_ptr->user_transform_depth = (png_byte)user_transform_depth;
+ png_ptr->user_transform_channels = (png_byte)user_transform_channels;
+#else
+ if (user_transform_ptr || user_transform_depth || user_transform_channels)
+ png_warning(png_ptr,
+ "This version of libpng does not support user transform info");
+#endif
+}
+
+/* This function returns a pointer to the user_transform_ptr associated with
+ * the user transform functions. The application should free any memory
+ * associated with this pointer before png_write_destroy and png_read_destroy
+ * are called.
+ */
+png_voidp PNGAPI
+png_get_user_transform_ptr(png_structp png_ptr)
+{
+ if (png_ptr == NULL)
+ return (NULL);
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
+ return ((png_voidp)png_ptr->user_transform_ptr);
+#else
+ return (NULL);
+#endif
+}
+#endif /* PNG_READ_USER_TRANSFORM_SUPPORTED ||
+ PNG_WRITE_USER_TRANSFORM_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */