mewin/libpng
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Imported from libpng-0.99.tar

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This commit is contained in:
Glenn Randers-Pehrson
1998-01-30 21:45:12 -06:00
parent c4a2ae6cac
commit 46f61e2398
25 changed files with 856 additions and 187 deletions
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10
example.c
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@@ -204,7 +204,7 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
/* If we don't have another value */
else
{
screen_gamma = 2.2; /* A good guess for a PC monitors in a brightly
screen_gamma = 2.2; /* A good guess for a PC monitors in a dimly
lit room */
screen_gamma = 1.7 or 1.0; /* A good guess for Mac systems */
}
@@ -223,7 +223,7 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
if (png_get_gAMA(png_ptr, info_ptr, &image_gamma)
png_set_gamma(png_ptr, screen_gamma, image_gamma);
else
png_set_gamma(png_ptr, screen_gamma, 0.51);
png_set_gamma(png_ptr, screen_gamma, 0.50);
/* Dither RGB files down to 8 bit palette or reduce palettes
* to the number of colors available on your screen.
@@ -255,7 +255,7 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
}
/* invert monocrome files to have 0 as white and 1 as black */
png_set_invert(png_ptr);
png_set_invert_mono(png_ptr);
/* If you want to shift the pixel values from the range [0,255] or
* [0,65535] to the original [0,7] or [0,31], or whatever range the
@@ -549,7 +549,7 @@ void write_png(char *file_name, ... other image information ...)
PNG_INTERLACE_????, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
/* set the palette if there is one. REQUIRED for indexed-color images */
palette = png_malloc(png_ptr, 256 * sizeof (png_color));
palette = (png_colorp)png_malloc(png_ptr, 256 * sizeof (png_color));
... set palette colors ...
png_set_PLTE(png_ptr, info_ptr, palette, 256);
@@ -600,7 +600,7 @@ void write_png(char *file_name, ... other image information ...)
*/
/* invert monocrome pixels */
png_set_invert(png_ptr);
png_set_invert_mono(png_ptr);
/* Shift the pixels up to a legal bit depth and fill in
* as appropriate to correctly scale the image.