/* pngtrans.c - transforms the data in a row (used by both readers and writers)
*
- * libpng 1.2.5rc3 - September 18, 2002
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2002 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.4 [July 7, 2011]
+ * Copyright (c) 1998-2011 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
-#include "png.h"
+#include "pngpriv.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* turn on BGR-to-RGB mapping */
+/* 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 */
+/* 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 */
+/* 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 */
+/* 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;
}
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
void PNGAPI
-png_set_shift(png_structp png_ptr, png_color_8p true_bits)
+png_set_shift(png_structp png_ptr, png_const_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;
}
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);
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.
+ /* 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
*/
}
/* Also I added this in libpng-1.0.2a (what happens when we expand
- * a less-than-8-bit grayscale to GA? */
+ * 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) || \
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
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
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 monochrome grayscale data */
+/* 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");
+ 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 defined(PNG_USELESS_TESTS_SUPPORTED)
- if (row == NULL || row_info == NULL)
- return;
-#endif
if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
{
png_bytep rp = row;
- png_uint_32 i;
- png_uint_32 istop = row_info->rowbytes;
+ png_size_t i;
+ png_size_t istop = row_info->rowbytes;
for (i = 0; i < istop; i++)
{
rp++;
}
}
+
else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
row_info->bit_depth == 8)
{
png_bytep rp = row;
- png_uint_32 i;
- png_uint_32 istop = row_info->rowbytes;
+ png_size_t i;
+ png_size_t istop = row_info->rowbytes;
- for (i = 0; i < istop; i+=2)
+ for (i = 0; i < istop; i += 2)
{
*rp = (png_byte)(~(*rp));
- rp+=2;
+ rp += 2;
}
}
+
+#ifdef PNG_16BIT_SUPPORTED
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;
+ png_size_t i;
+ png_size_t istop = row_info->rowbytes;
- for (i = 0; i < istop; i+=4)
+ for (i = 0; i < istop; i += 4)
{
*rp = (png_byte)(~(*rp));
- *(rp+1) = (png_byte)(~(*(rp+1)));
- rp+=4;
+ *(rp + 1) = (png_byte)(~(*(rp + 1)));
+ rp += 4;
}
}
+#endif
}
#endif
+#ifdef PNG_16BIT_SUPPORTED
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* swaps byte order on 16 bit depth images */
+/* 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");
- if (
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- row != NULL && row_info != NULL &&
-#endif
- row_info->bit_depth == 16)
+ png_debug(1, "in png_do_swap");
+
+ if (row_info->bit_depth == 16)
{
png_bytep rp = row;
png_uint_32 i;
}
}
#endif
+#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 */
+/* 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");
- if (
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- row != NULL && row_info != NULL &&
-#endif
- row_info->bit_depth < 8)
+ png_debug(1, "in png_do_packswap");
+
+ if (row_info->bit_depth < 8)
{
- png_bytep rp, end, table;
+ png_bytep rp;
+ png_const_bytep end, table;
end = row + row_info->rowbytes;
if (row_info->bit_depth == 1)
table = onebppswaptable;
+
else if (row_info->bit_depth == 2)
table = twobppswaptable;
+
else if (row_info->bit_depth == 4)
table = fourbppswaptable;
+
else
return;
#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-/* remove filler or alpha byte(s) */
+/* Remove a channel - this used to be 'png_do_strip_filler' but it used a
+ * somewhat weird combination of flags to determine what to do. All the calls
+ * to png_do_strip_filler are changed in 1.5.2 to call this instead with the
+ * correct arguments.
+ *
+ * The routine isn't general - the channel must be the channel at the start or
+ * end (not in the middle) of each pixel.
+ */
void /* PRIVATE */
-png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags)
+png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
{
- png_debug(1, "in png_do_strip_filler\n");
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- if (row != NULL && row_info != NULL)
-#endif
+ png_bytep sp = row; /* source pointer */
+ png_bytep dp = row; /* destination pointer */
+ png_bytep ep = row + row_info->rowbytes; /* One beyond end of row */
+
+ /* At the start sp will point to the first byte to copy and dp to where
+ * it is copied to. ep always points just beyond the end of the row, so
+ * the loop simply copies (channels-1) channels until sp reaches ep.
+ *
+ * at_start: 0 -- convert AG, XG, ARGB, XRGB, AAGG, XXGG, etc.
+ * nonzero -- convert GA, GX, RGBA, RGBX, GGAA, RRGGBBXX, etc.
+ */
+
+ /* GA, GX, XG cases */
+ if (row_info->channels == 2)
{
-/*
- if (row_info->color_type == PNG_COLOR_TYPE_RGB ||
- row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-*/
- png_bytep sp=row;
- png_bytep dp=row;
- png_uint_32 row_width=row_info->width;
- png_uint_32 i;
+ if (row_info->bit_depth == 8)
+ {
+ if (at_start) /* Skip initial filler */
+ ++sp;
+ else /* Skip initial channel and, for sp, the filler */
+ sp += 2, ++dp;
+
+ /* For a 1 pixel wide image there is nothing to do */
+ while (sp < ep)
+ *dp++ = *sp, sp += 2;
- if (row_info->channels == 4)
+ row_info->pixel_depth = 8;
+ }
+
+ else if (row_info->bit_depth == 16)
{
- if (row_info->bit_depth == 8)
- {
- /* This converts from RGBX or RGBA to RGB */
- if (flags & PNG_FLAG_FILLER_AFTER)
- {
- dp+=3; sp+=4;
- for (i = 1; i < row_width; i++)
- {
- *dp++ = *sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- sp++;
- }
- }
- /* This converts from XRGB or ARGB to RGB */
- else
- {
- for (i = 0; i < row_width; i++)
- {
- sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- }
- }
- row_info->pixel_depth = 24;
- row_info->rowbytes = row_width * 3;
- }
- else /* if (row_info->bit_depth == 16) */
- {
- if (flags & PNG_FLAG_FILLER_AFTER)
- {
- /* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */
- sp += 8; dp += 6;
- for (i = 1; i < row_width; i++)
- {
- /* This could be (although png_memcpy is probably slower):
- png_memcpy(dp, sp, 6);
- sp += 8;
- dp += 6;
- */
-
- *dp++ = *sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- sp += 2;
- }
- }
- else
- {
- /* This converts from XXRRGGBB or AARRGGBB to RRGGBB */
- for (i = 0; i < row_width; i++)
- {
- /* 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++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- *dp++ = *sp++;
- }
- }
- row_info->pixel_depth = 48;
- row_info->rowbytes = row_width * 6;
- }
- row_info->channels = 3;
- row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
+ if (at_start) /* Skip initial filler */
+ sp += 2;
+ else /* Skip initial channel and, for sp, the filler */
+ sp += 4, dp += 2;
+
+ while (sp < ep)
+ *dp++ = *sp++, *dp++ = *sp, sp += 3;
+
+ row_info->pixel_depth = 16;
+ }
+
+ else
+ return; /* bad bit depth */
+
+ row_info->channels = 1;
+
+ /* Finally fix the color type if it records an alpha channel */
+ if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ row_info->color_type = PNG_COLOR_TYPE_GRAY;
+ }
+
+ /* RGBA, RGBX, XRGB cases */
+ else if (row_info->channels == 4)
+ {
+ if (row_info->bit_depth == 8)
+ {
+ if (at_start) /* Skip initial filler */
+ ++sp;
+ else /* Skip initial channels and, for sp, the filler */
+ sp += 4, dp += 3;
+
+ /* Note that the loop adds 3 to dp and 4 to sp each time. */
+ while (sp < ep)
+ *dp++ = *sp++, *dp++ = *sp++, *dp++ = *sp, sp += 2;
+
+ row_info->pixel_depth = 24;
}
-/*
- 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->bit_depth == 16)
{
- if (row_info->bit_depth == 8)
- {
- /* This converts from GX or GA to G */
- if (flags & PNG_FLAG_FILLER_AFTER)
- {
- for (i = 0; i < row_width; i++)
- {
- *dp++ = *sp++;
- sp++;
- }
- }
- /* This converts from XG or AG to G */
- else
- {
- for (i = 0; i < row_width; i++)
- {
- sp++;
- *dp++ = *sp++;
- }
- }
- row_info->pixel_depth = 8;
- row_info->rowbytes = row_width;
- }
- else /* if (row_info->bit_depth == 16) */
+ if (at_start) /* Skip initial filler */
+ sp += 2;
+ else /* Skip initial channels and, for sp, the filler */
+ sp += 8, dp += 6;
+
+ while (sp < ep)
{
- if (flags & PNG_FLAG_FILLER_AFTER)
- {
- /* This converts from GGXX or GGAA to GG */
- sp += 4; dp += 2;
- for (i = 1; i < row_width; i++)
- {
- *dp++ = *sp++;
- *dp++ = *sp++;
- sp += 2;
- }
- }
- else
- {
- /* This converts from XXGG or AAGG to GG */
- for (i = 0; i < row_width; i++)
- {
- sp += 2;
- *dp++ = *sp++;
- *dp++ = *sp++;
- }
- }
- row_info->pixel_depth = 16;
- row_info->rowbytes = row_width * 2;
+ /* Copy 6 bytes, skip 2 */
+ *dp++ = *sp++, *dp++ = *sp++;
+ *dp++ = *sp++, *dp++ = *sp++;
+ *dp++ = *sp++, *dp++ = *sp, sp += 3;
}
- row_info->channels = 1;
- row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
+
+ row_info->pixel_depth = 48;
}
+
+ else
+ return; /* bad bit depth */
+
+ row_info->channels = 3;
+
+ /* Finally fix the color type if it records an alpha channel */
+ if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ row_info->color_type = PNG_COLOR_TYPE_RGB;
}
+
+ else
+ return; /* The filler channel has gone already */
+
+ /* Fix the rowbytes value. */
+ row_info->rowbytes = dp-row;
}
#endif
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* swaps red and blue bytes within a pixel */
+/* 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");
- if (
-#if defined(PNG_USELESS_TESTS_SUPPORTED)
- row != NULL && row_info != NULL &&
-#endif
- (row_info->color_type & PNG_COLOR_MASK_COLOR))
+ png_debug(1, "in png_do_bgr");
+
+ if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
{
png_uint_32 row_width = row_info->width;
if (row_info->bit_depth == 8)
*(rp + 2) = save;
}
}
+
else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
{
png_bytep rp;
}
}
}
+
+#ifdef PNG_16BIT_SUPPORTED
else if (row_info->bit_depth == 16)
{
if (row_info->color_type == PNG_COLOR_TYPE_RGB)
*(rp + 5) = save;
}
}
+
else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
{
png_bytep rp;
}
}
}
+#endif
}
}
#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
- defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
- defined(PNG_LEGACY_SUPPORTED)
+ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+#ifdef PNG_USER_TRANSFORM_PTR_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\n");
-#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+ png_debug(1, "in png_set_user_transform_info");
+
+ if (png_ptr == NULL)
+ return;
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
}
#endif
* associated with this pointer before png_write_destroy and png_read_destroy
* are called.
*/
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
png_voidp PNGAPI
-png_get_user_transform_ptr(png_structp png_ptr)
+png_get_user_transform_ptr(png_const_structp png_ptr)
{
-#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+ if (png_ptr == NULL)
+ return (NULL);
+
return ((png_voidp)png_ptr->user_transform_ptr);
-#else
- if(png_ptr)
- return (NULL);
- return (NULL);
+}
#endif
+
+#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
+png_uint_32 PNGAPI
+png_get_current_row_number(png_const_structp png_ptr)
+{
+ /* See the comments in png.h - this is the sub-image row when reading and
+ * interlaced image.
+ */
+ if (png_ptr != NULL)
+ return png_ptr->row_number;
+
+ return PNG_UINT_32_MAX; /* help the app not to fail silently */
+}
+
+png_byte PNGAPI
+png_get_current_pass_number(png_const_structp png_ptr)
+{
+ if (png_ptr != NULL)
+ return png_ptr->pass;
+ return 8; /* invalid */
}
+#endif /* PNG_USER_TRANSFORM_INFO_SUPPORTED */
+#endif /* PNG_READ_USER_TRANSFORM_SUPPORTED ||
+ PNG_WRITE_USER_TRANSFORM_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
projects / wxWidgets.git / blobdiff