/* pngrtran.c - transforms the data in a row for PNG readers
*
- * libpng version 1.2.8 - December 3, 2004
+ * Last changed in libpng 1.2.27 [April 29, 2008]
* For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * 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.)
*
#define PNG_INTERNAL
#include "png.h"
+#if defined(PNG_READ_SUPPORTED)
+
/* Set the action on getting a CRC error for an ancillary or critical chunk. */
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");
/* 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 */
int need_expand, double background_gamma)
{
png_debug(1, "in png_set_background\n");
+ 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->background_gamma = (float)background_gamma;
png_ptr->background_gamma_type = (png_byte)(background_gamma_code);
png_ptr->transformations |= (need_expand ? PNG_BACKGROUND_EXPAND : 0);
-
- /* Note: if need_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 ((need_expand && !(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) ||
- (!need_expand && background_color->red == background_color->green &&
- background_color->red == background_color->blue))
- png_ptr->mode |= PNG_BACKGROUND_IS_GRAY;
}
#endif
png_set_strip_16(png_structp png_ptr)
{
png_debug(1, "in png_set_strip_16\n");
+ if(png_ptr == NULL) return;
png_ptr->transformations |= PNG_16_TO_8;
}
#endif
png_set_strip_alpha(png_structp png_ptr)
{
png_debug(1, "in png_set_strip_alpha\n");
+ if(png_ptr == NULL) return;
png_ptr->flags |= PNG_FLAG_STRIP_ALPHA;
}
#endif
int full_dither)
{
png_debug(1, "in png_set_dither\n");
+ if(png_ptr == NULL) return;
png_ptr->transformations |= PNG_DITHER;
if (!full_dither)
png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma)
{
png_debug(1, "in png_set_gamma\n");
+ 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_set_expand(png_structp png_ptr)
{
png_debug(1, "in png_set_expand\n");
- png_ptr->transformations |= PNG_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
*
* 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_expand\n");
+ png_debug(1, "in png_set_palette_to_rgb\n");
+ 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\n");
+ 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_expand\n");
- png_ptr->transformations |= PNG_EXPAND;
+ png_debug(1, "in png_set_gray_1_2_4_to_8\n");
+ 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_expand\n");
- png_ptr->transformations |= PNG_EXPAND;
+ png_debug(1, "in png_set_tRNS_to_alpha\n");
+ png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
+ png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
}
#endif /* defined(PNG_READ_EXPAND_SUPPORTED) */
{
png_debug(1, "in png_set_gray_to_rgb\n");
png_ptr->transformations |= PNG_GRAY_TO_RGB;
+ png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
}
#endif
{
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
png_fixed_point red, png_fixed_point green)
{
png_debug(1, "in png_set_rgb_to_gray\n");
+ if(png_ptr == NULL) return;
switch(error_action)
{
case 1: png_ptr->transformations |= PNG_RGB_TO_GRAY;
read_user_transform_fn)
{
png_debug(1, "in png_set_read_user_transform_fn\n");
+ 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
#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
+
+#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)
+ {
+ 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;
+ 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;
+ 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;
+ 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:
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
k=1; /* partial transparency is present */
}
if (k == 0)
- png_ptr->transformations &= (~PNG_GAMMA);
+ png_ptr->transformations &= ~PNG_GAMMA;
}
- if (png_ptr->transformations & (PNG_GAMMA | PNG_RGB_TO_GRAY))
+ 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)
{
- /* could skip if no transparency and
+ /* could skip if no transparency and
*/
png_color back, back_1;
png_colorp palette = png_ptr->palette;
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) */
else
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)
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 /* PNG_READ_BACKGROUND_SUPPORTED */
{
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;
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)
{
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 (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
info_ptr->channels = 1;
else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
png_do_read_transformations(png_structp png_ptr)
{
png_debug(1, "in png_do_read_transformations\n");
-#if !defined(PNG_USELESS_TESTS_SUPPORTED)
if (png_ptr->row_buf == NULL)
{
#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", 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)
}
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
if(rgb_error)
{
png_ptr->rgb_to_gray_status=1;
- if(png_ptr->transformations == PNG_RGB_TO_GRAY_WARN)
+ 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_ERR)
+ 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");
}
}
}
}
-/* 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 /* PRIVATE */
png_do_expand(png_row_infop row_info, png_bytep row,
{
case 1:
{
- gray = (png_uint_16)(gray*0xff);
+ 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);
}
case 2:
{
- gray = (png_uint_16)(gray*0x55);
+ 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);
}
case 4:
{
- gray = (png_uint_16)(gray*0x11);
+ 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);
{
if (row_info->bit_depth == 8)
{
+ 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++)
}
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_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;
{
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_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_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;
#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
png_build_gamma_table(png_structp png_ptr)
{
png_debug(1, "in png_build_gamma_table\n");
- if(png_ptr->gamma != 0.0)
+
+ if (png_ptr->bit_depth <= 8)
{
- if (png_ptr->bit_depth <= 8)
- {
- int i;
- double g;
+ int i;
+ double g;
- if (png_ptr->screen_gamma > .000001)
- g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
- else
- g = 1.0;
+ if (png_ptr->screen_gamma > .000001)
+ g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+ else
+ g = 1.0;
- png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr,
- (png_uint_32)256);
+ png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)256);
- for (i = 0; i < 256; i++)
- {
- png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0,
- g) * 255.0 + .5);
- }
+ for (i = 0; i < 256; i++)
+ {
+ png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0,
+ g) * 255.0 + .5);
+ }
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
- defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
- if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY))
- {
+ defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY))
+ {
- g = 1.0 / (png_ptr->gamma);
+ g = 1.0 / (png_ptr->gamma);
- png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr,
- (png_uint_32)256);
+ png_ptr->gamma_to_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_to_1[i] = (png_byte)(pow((double)i / 255.0,
+ g) * 255.0 + .5);
+ }
- png_ptr->gamma_from_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);
- 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->screen_gamma > 0.000001)
+ g = 1.0 / png_ptr->screen_gamma;
+ else
+ g = png_ptr->gamma; /* probably doing rgb_to_gray */
- for (i = 0; i < 256; i++)
- {
- png_ptr->gamma_from_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_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
- }
- else
- {
- double g;
- int i, j, shift, num;
- int sig_bit;
- png_uint_32 ig;
+ }
+ 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 (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 (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 (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;
+ if (shift > 8)
+ shift = 8;
+ if (shift < 0)
+ shift = 0;
- png_ptr->gamma_shift = (png_byte)shift;
+ png_ptr->gamma_shift = (png_byte)shift;
- num = (1 << (8 - 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;
+ 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)));
+ 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;
+ 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)));
- }
+ 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)));
+ }
- 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)));
+ 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)));
- 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);
- }
- }
- }
+ 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);
+ }
+ }
+ }
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
- defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
- if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY))
- {
+ defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+ if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY))
+ {
- g = 1.0 / (png_ptr->gamma);
+ g = 1.0 / (png_ptr->gamma);
- png_ptr->gamma_16_to_1 = (png_uint_16pp)png_malloc(png_ptr,
- (png_uint_32)(num * png_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 )));
- 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_to_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_to_1[i][j] =
- (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
- 65535.0, g) * 65535.0 + .5);
- }
- }
+ 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);
+ }
+ }
- 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->screen_gamma > 0.000001)
+ g = 1.0 / png_ptr->screen_gamma;
+ else
+ g = png_ptr->gamma; /* probably doing rgb_to_gray */
- png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr,
- (png_uint_32)(num * png_sizeof (png_uint_16p)));
+ png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr,
+ (png_uint_32)(num * png_sizeof (png_uint_16p)));
- 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)));
+ 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);
- }
- }
- }
+ 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 /* PNG_MNG_FEATURES_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED */
projects / opencv / blobdiff