/* pngwtran.c - transforms the data in a row for PNG writers
*
- * libpng 1.0.3 - January 14, 1999
+ * Last changed in libpng 1.2.9 April 14, 2006
* 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, 1999 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2006 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.)
*/
#define PNG_INTERNAL
#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
/* Transform the data according to the user's wishes. The order of
* transformations is significant.
*/
-void
+void /* PRIVATE */
png_do_write_transformations(png_structp png_ptr)
{
png_debug(1, "in png_do_write_transformations\n");
+ if (png_ptr == NULL)
+ return;
+
#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
if (png_ptr->transformations & PNG_USER_TRANSFORM)
if(png_ptr->write_user_transform_fn != NULL)
png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1,
&(png_ptr->shift));
#endif
-#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
- if (png_ptr->transformations & PNG_INVERT_ALPHA)
- png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
-#endif
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
if (png_ptr->transformations & PNG_SWAP_ALPHA)
png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
#endif
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+ if (png_ptr->transformations & PNG_INVERT_ALPHA)
+ png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
#if defined(PNG_WRITE_BGR_SUPPORTED)
if (png_ptr->transformations & PNG_BGR)
png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
* row_info bit depth should be 8 (one pixel per byte). The channels
* should be 1 (this only happens on grayscale and paletted images).
*/
-void
+void /* PRIVATE */
png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
{
png_debug(1, "in png_do_pack\n");
{
png_byte value;
- value = (png_byte)(*sp & 0x3);
+ value = (png_byte)(*sp & 0x03);
v |= (value << shift);
if (shift == 0)
{
{
png_byte value;
- value = (png_byte)(*sp & 0xf);
+ value = (png_byte)(*sp & 0x0f);
v |= (value << shift);
if (shift == 0)
}
row_info->bit_depth = (png_byte)bit_depth;
row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels);
- row_info->rowbytes =
- ((row_info->width * row_info->pixel_depth + 7) >> 3);
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+ row_info->width);
}
}
#endif
* would pass 3 as bit_depth, and this routine would translate the
* data to 0 to 15.
*/
-void
+void /* PRIVATE */
png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
{
png_debug(1, "in png_do_shift\n");
png_uint_16 value, v;
int j;
- v = ((png_uint_16)(*bp) << 8) + *(bp + 1);
+ v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1));
value = 0;
for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
{
#endif
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-void
+void /* PRIVATE */
png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
{
png_debug(1, "in png_do_write_swap_alpha\n");
#endif
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-void
+void /* PRIVATE */
png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
{
png_debug(1, "in png_do_write_invert_alpha\n");
png_uint_32 row_width = row_info->width;
for (i = 0, sp = dp = row; i < row_width; i++)
{
+ /* does nothing
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
- *(dp++) = 255 - *(sp++);
+ */
+ sp+=3; dp = sp;
+ *(dp++) = (png_byte)(255 - *(sp++));
}
}
/* This inverts the alpha channel in RRGGBBAA */
for (i = 0, sp = dp = row; i < row_width; i++)
{
+ /* does nothing
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
- *(dp++) = 255 - *(sp++);
- *(dp++) = 255 - *(sp++);
+ */
+ sp+=6; dp = sp;
+ *(dp++) = (png_byte)(255 - *(sp++));
+ *(dp++) = (png_byte)(255 - *(sp++));
}
}
}
for (i = 0, sp = dp = row; i < row_width; i++)
{
*(dp++) = *(sp++);
- *(dp++) = 255 - *(sp++);
+ *(dp++) = (png_byte)(255 - *(sp++));
}
}
/* This inverts the alpha channel in GGAA */
for (i = 0, sp = dp = row; i < row_width; i++)
{
+ /* does nothing
*(dp++) = *(sp++);
*(dp++) = *(sp++);
- *(dp++) = 255 - *(sp++);
- *(dp++) = 255 - *(sp++);
+ */
+ sp+=2; dp = sp;
+ *(dp++) = (png_byte)(255 - *(sp++));
+ *(dp++) = (png_byte)(255 - *(sp++));
}
}
}
}
}
#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+/* undoes intrapixel differencing */
+void /* PRIVATE */
+png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
+{
+ png_debug(1, "in png_do_write_intrapixel\n");
+ 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)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ 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, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ *(rp) = (png_byte)((*rp - *(rp+1))&0xff);
+ *(rp+2) = (png_byte)((*(rp+2) - *(rp+1))&0xff);
+ }
+ }
+ else if (row_info->bit_depth == 16)
+ {
+ png_bytep rp;
+ png_uint_32 i;
+
+ 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, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+ {
+ png_uint_32 s0 = (*(rp ) << 8) | *(rp+1);
+ png_uint_32 s1 = (*(rp+2) << 8) | *(rp+3);
+ png_uint_32 s2 = (*(rp+4) << 8) | *(rp+5);
+ png_uint_32 red = (png_uint_32)((s0-s1) & 0xffffL);
+ png_uint_32 blue = (png_uint_32)((s2-s1) & 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_MNG_FEATURES_SUPPORTED */
+#endif /* PNG_WRITE_SUPPORTED */
projects / wxWidgets.git / blobdiff