/* pngtrans.c - transforms the data in a row (used by both readers and writers)
*
- * Last changed in libpng 1.5.4 [July 7, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.2 [April 25, 2013]
+ * Copyright (c) 1998-2013 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.)
*
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* Turn on BGR-to-RGB mapping */
void PNGAPI
-png_set_bgr(png_structp png_ptr)
+png_set_bgr(png_structrp png_ptr)
{
png_debug(1, "in png_set_bgr");
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* Turn on 16 bit byte swapping */
void PNGAPI
-png_set_swap(png_structp png_ptr)
+png_set_swap(png_structrp png_ptr)
{
png_debug(1, "in png_set_swap");
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
/* Turn on pixel packing */
void PNGAPI
-png_set_packing(png_structp png_ptr)
+png_set_packing(png_structrp png_ptr)
{
png_debug(1, "in png_set_packing");
#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
/* Turn on packed pixel swapping */
void PNGAPI
-png_set_packswap(png_structp png_ptr)
+png_set_packswap(png_structrp png_ptr)
{
png_debug(1, "in png_set_packswap");
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
void PNGAPI
-png_set_shift(png_structp png_ptr, png_const_color_8p true_bits)
+png_set_shift(png_structrp png_ptr, png_const_color_8p true_bits)
{
png_debug(1, "in png_set_shift");
#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
defined(PNG_WRITE_INTERLACING_SUPPORTED)
int PNGAPI
-png_set_interlace_handling(png_structp png_ptr)
+png_set_interlace_handling(png_structrp png_ptr)
{
png_debug(1, "in png_set_interlace handling");
* that don't like bytes as parameters.
*/
void PNGAPI
-png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc)
+png_set_filler(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
{
png_debug(1, "in png_set_filler");
if (png_ptr == NULL)
return;
+ /* In libpng 1.6 it is possible to determine whether this is a read or write
+ * operation and therefore to do more checking here for a valid call.
+ */
+ if (png_ptr->mode & PNG_IS_READ_STRUCT)
+ {
+# ifdef PNG_READ_FILLER_SUPPORTED
+ /* On read png_set_filler is always valid, regardless of the base PNG
+ * format, because other transformations can give a format where the
+ * filler code can execute (basically an 8 or 16-bit component RGB or G
+ * format.)
+ *
+ * NOTE: usr_channels is not used by the read code! (This has led to
+ * confusion in the past.) The filler is only used in the read code.
+ */
+ png_ptr->filler = (png_uint_16)filler;
+# else
+ png_app_error(png_ptr, "png_set_filler not supported on read");
+ PNG_UNUSED(filler) /* not used in the write case */
+ return;
+# endif
+ }
+
+ else /* write */
+ {
+# ifdef PNG_WRITE_FILLER_SUPPORTED
+ /* On write the usr_channels parameter must be set correctly at the
+ * start to record the number of channels in the app-supplied data.
+ */
+ switch (png_ptr->color_type)
+ {
+ case PNG_COLOR_TYPE_RGB:
+ png_ptr->usr_channels = 4;
+ break;
+
+ case PNG_COLOR_TYPE_GRAY:
+ if (png_ptr->bit_depth >= 8)
+ {
+ png_ptr->usr_channels = 2;
+ break;
+ }
+
+ else
+ {
+ /* There simply isn't any code in libpng to strip out bits
+ * from bytes when the components are less than a byte in
+ * size!
+ */
+ png_app_error(png_ptr,
+ "png_set_filler is invalid for low bit depth gray output");
+ return;
+ }
+
+ default:
+ png_app_error(png_ptr,
+ "png_set_filler: inappropriate color type");
+ return;
+ }
+# else
+ png_app_error(png_ptr, "png_set_filler not supported on write");
+ return;
+# endif
+ }
+
+ /* Here on success - libpng supports the operation, set the transformation
+ * and the flag to say where the filler channel is.
+ */
png_ptr->transformations |= PNG_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_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_set_add_alpha(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
{
png_debug(1, "in png_set_add_alpha");
return;
png_set_filler(png_ptr, filler, filler_loc);
- png_ptr->transformations |= PNG_ADD_ALPHA;
+ /* The above may fail to do anything. */
+ if (png_ptr->transformations & PNG_FILLER)
+ png_ptr->transformations |= PNG_ADD_ALPHA;
}
#endif
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
void PNGAPI
-png_set_swap_alpha(png_structp png_ptr)
+png_set_swap_alpha(png_structrp png_ptr)
{
png_debug(1, "in png_set_swap_alpha");
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
void PNGAPI
-png_set_invert_alpha(png_structp png_ptr)
+png_set_invert_alpha(png_structrp png_ptr)
{
png_debug(1, "in png_set_invert_alpha");
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
void PNGAPI
-png_set_invert_mono(png_structp png_ptr)
+png_set_invert_mono(png_structrp png_ptr)
{
png_debug(1, "in png_set_invert_mono");
}
#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+ defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+/* Added at libpng-1.5.10 */
+void /* PRIVATE */
+png_do_check_palette_indexes(png_structrp png_ptr, png_row_infop row_info)
+{
+ if (png_ptr->num_palette < (1 << row_info->bit_depth) &&
+ png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */
+ {
+ /* Calculations moved outside switch in an attempt to stop different
+ * compiler warnings. 'padding' is in *bits* within the last byte, it is
+ * an 'int' because pixel_depth becomes an 'int' in the expression below,
+ * and this calculation is used because it avoids warnings that other
+ * forms produced on either GCC or MSVC.
+ */
+ int padding = (-row_info->pixel_depth * row_info->width) & 7;
+ png_bytep rp = png_ptr->row_buf + row_info->rowbytes;
+
+ switch (row_info->bit_depth)
+ {
+ case 1:
+ {
+ /* in this case, all bytes must be 0 so we don't need
+ * to unpack the pixels except for the rightmost one.
+ */
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ if (*rp >> padding != 0)
+ png_ptr->num_palette_max = 1;
+ padding = 0;
+ }
+
+ break;
+ }
+
+ case 2:
+ {
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ int i = ((*rp >> padding) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 2) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 4) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 6) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ padding = 0;
+ }
+
+ break;
+ }
+
+ case 4:
+ {
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ int i = ((*rp >> padding) & 0x0f);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 4) & 0x0f);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ padding = 0;
+ }
+
+ break;
+ }
+
+ case 8:
+ {
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ if (*rp > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = (int) *rp;
+ }
+
+ break;
+ }
+
+ default:
+ break;
+ }
+ }
+}
+#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */
+
#if defined(PNG_READ_USER_TRANSFORM_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
+png_set_user_transform_info(png_structrp 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_READ_USER_TRANSFORM_SUPPORTED
+ if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
+ (png_ptr->flags & PNG_FLAG_ROW_INIT) != 0)
+ {
+ png_app_error(png_ptr,
+ "info change after png_start_read_image or png_read_update_info");
+ return;
+ }
+#endif
+
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;
*/
#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
png_voidp PNGAPI
-png_get_user_transform_ptr(png_const_structp png_ptr)
+png_get_user_transform_ptr(png_const_structrp png_ptr)
{
if (png_ptr == NULL)
return (NULL);
- return ((png_voidp)png_ptr->user_transform_ptr);
+ return png_ptr->user_transform_ptr;
}
#endif
#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
png_uint_32 PNGAPI
-png_get_current_row_number(png_const_structp png_ptr)
+png_get_current_row_number(png_const_structrp png_ptr)
{
/* See the comments in png.h - this is the sub-image row when reading and
* interlaced image.
}
png_byte PNGAPI
-png_get_current_pass_number(png_const_structp png_ptr)
+png_get_current_pass_number(png_const_structrp png_ptr)
{
if (png_ptr != NULL)
return png_ptr->pass;