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Imported from libpng-1.0.5h.tar

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This commit is contained in:
Glenn Randers-Pehrson
1999-12-10 09:43:02 -06:00
parent 074af5e9ca
commit 166c5a397e
62 changed files with 3740 additions and 1045 deletions
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45
pngrtran.c
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@@ -1,7 +1,7 @@
/* pngrtran.c - transforms the data in a row for PNG readers
*
* libpng 1.0.5d - November 29, 1999
* libpng 1.0.5h - December 10, 1999
* 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
@@ -69,7 +69,8 @@ png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action)
}
}
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
defined(PNG_FLOATING_POINT_SUPPORTED)
/* handle alpha and tRNS via a background color */
void
png_set_background(png_structp png_ptr,
@@ -504,7 +505,7 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
}
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED)
#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
/* Transform the image from the file_gamma to the screen_gamma. We
* only do transformations on images where the file_gamma and screen_gamma
* are not close reciprocals, otherwise it slows things down slightly, and
@@ -581,7 +582,8 @@ png_set_gray_to_rgb(png_structp png_ptr)
}
#endif
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) && \
defined(PNG_FLOATING_POINT_SUPPORTED)
/* Convert a RGB image to a grayscale of the same width. This allows us,
* for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image.
*/
@@ -718,7 +720,7 @@ png_init_read_transformations(png_structp png_ptr)
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
png_ptr->background_1 = png_ptr->background;
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED)
#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
if (png_ptr->transformations & (PNG_GAMMA | PNG_RGB_TO_GRAY))
{
png_build_gamma_table(png_ptr);
@@ -731,7 +733,6 @@ png_init_read_transformations(png_structp png_ptr)
png_colorp palette = png_ptr->palette;
int num_palette = png_ptr->num_palette;
int i;
if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE)
{
back.red = png_ptr->gamma_table[png_ptr->background.red];
@@ -789,7 +790,6 @@ png_init_read_transformations(png_structp png_ptr)
back_1.blue = (png_byte)(pow(
(double)png_ptr->background.blue/255, g) * 255.0 + .5);
}
for (i = 0; i < num_palette; i++)
{
if (i < (int)png_ptr->num_trans && png_ptr->trans[i] != 0xff)
@@ -998,8 +998,15 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
#if defined(PNG_READ_GAMMA_SUPPORTED)
if (png_ptr->transformations & PNG_GAMMA)
{
#ifdef PNG_FLOATING_POINT_SUPPORTED
info_ptr->gamma = png_ptr->gamma;
#endif
#ifdef PNG_FIXED_POINT_SUPPORTED
info_ptr->int_gamma = png_ptr->int_gamma;
#endif
}
#endif
#if defined(PNG_READ_16_TO_8_SUPPORTED)
if ((png_ptr->transformations & PNG_16_TO_8) && info_ptr->bit_depth == 16)
@@ -1290,7 +1297,7 @@ From Andreas Dilger e-mail to png-implement, 26 March 1998:
png_ptr->row_info.channels = png_ptr->user_transform_channels;
png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
png_ptr->row_info.channels);
png_ptr->row_info.rowbytes = (png_ptr->row_info.width *
png_ptr->row_info.rowbytes = (png_ptr->row_info.width *
png_ptr->row_info.pixel_depth+7)>>3;
}
#endif
@@ -1988,7 +1995,7 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
#endif
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
/* reduce RGB files to grayscale, with or without alpha
/* reduce RGB files to grayscale, with or without alpha
* using the equation given in Poynton's ColorFAQ at
* <http://www.inforamp.net/~poynton/>
* Copyright (c) 1998-01-04 Charles Poynton poynton@inforamp.net
@@ -1996,7 +2003,7 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
* Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
*
* We approximate this with
*
*
* Y = 0.211 * R + 0.715 * G + 0.074 * B
*
* which can be expressed with integers as
@@ -2072,7 +2079,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
}
}
}
else /* RGB bit_depth == 16 */
{
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
@@ -2097,7 +2104,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
png_ptr->gamma_shift][red>>8];
png_uint_16 green_1 = png_ptr->gamma_16_to_1[(green&0xff) >>
png_ptr->gamma_shift][green>>8];
png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >>
png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >>
png_ptr->gamma_shift][blue>>8];
png_uint_16 gray16 = (png_uint_16)((rc*red_1 + gc*green_1
+ bc*blue_1)>>8);
@@ -2105,7 +2112,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
png_ptr->gamma_shift][gray16 >> 8];
rgb_error |= 1;
}
*(dp++) = (png_byte)((w>>8) & 0xff);
*(dp++) = (png_byte)(w & 0xff);
}
@@ -2194,7 +2201,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
png_ptr->gamma_shift][red>>8];
png_uint_16 green_1 = png_ptr->gamma_16_to_1[(green&0xff) >>
png_ptr->gamma_shift][green>>8];
png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >>
png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >>
png_ptr->gamma_shift][blue>>8];
png_uint_16 gray16 = (png_uint_16)((rc * red_1
+ gc * green_1 + bc * blue_1)>>8);
@@ -2202,7 +2209,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
png_ptr->gamma_shift][gray16 >> 8];
rgb_error |= 1;
}
*(dp++) = (png_byte)((w>>8) & 0xff);
*(dp++) = (png_byte)(w & 0xff);
*(dp++) = *(sp++); /* alpha */
@@ -2298,7 +2305,8 @@ png_correct_palette(png_structp png_ptr, png_colorp palette,
int num_palette)
{
png_debug(1, "in png_correct_palette\n");
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
if (png_ptr->transformations & (PNG_GAMMA | PNG_BACKGROUND))
{
png_color back, back_1;
@@ -3764,6 +3772,7 @@ png_do_dither(png_row_infop row_info, png_bytep row,
}
#endif
#ifdef PNG_FLOATING_POINT_SUPPORTED
#if defined(PNG_READ_GAMMA_SUPPORTED)
static int png_gamma_shift[] =
{0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0};
@@ -3814,7 +3823,7 @@ png_build_gamma_table(png_structp png_ptr)
g) * 255.0 + .5);
}
png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr,
(png_uint_32)256);
@@ -3983,4 +3992,6 @@ png_build_gamma_table(png_structp png_ptr)
}
}
#endif
/* To do: install integer version of png_build_gamma_table here */
#endif