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[libpng16] Imported from libpng-1.6.0beta05.tar

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Glenn Randers-Pehrson
2012-02-02 23:11:45 -06:00
parent 96cf4bde0e
commit f3af706c2a
186 changed files with 8544 additions and 20666 deletions
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86
example.c
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@@ -2,8 +2,8 @@
#if 0 /* in case someone actually tries to compile this */
/* example.c - an example of using libpng
* Last changed in libpng 1.6.0 [February 14, 2013]
* Maintained 1998-2013 Glenn Randers-Pehrson
* Last changed in libpng 1.6.0 [(PENDING RELEASE)]
* Maintained 1998-2012 Glenn Randers-Pehrson
* Maintained 1996, 1997 Andreas Dilger)
* Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
* To the extent possible under law, the authors have waived
@@ -48,8 +48,7 @@ int main(int argc, const char **argv)
png_image image; /* The control structure used by libpng */
/* Initialize the 'png_image' structure. */
memset(&image, 0, (sizeof image));
image.version = PNG_IMAGE_VERSION;
memset(&image, 0, sizeof image);
/* The first argument is the file to read: */
if (png_image_begin_read_from_file(&image, argv[1]))
@@ -76,28 +75,16 @@ int main(int argc, const char **argv)
* be supplied or the output buffer would have to be initialized to the
* actual background of the image.
*
* The fourth argument to png_image_finish_read is the 'row_stride' -
* The final argument to png_image_finish_read is the 'row_stride' -
* this is the number of components allocated for the image in each
* row. It has to be at least as big as the value returned by
* PNG_IMAGE_ROW_STRIDE, but if you just allocate space for the
* default, minimum, size using PNG_IMAGE_SIZE as above you can pass
* zero.
*
* The final argument is a pointer to a buffer for the colormap;
* colormaps have exactly the same format as a row of image pixels (so
* you choose what format to make the colormap by setting
* image.format). A colormap is only returned if
* PNG_FORMAT_FLAG_COLORMAP is also set in image.format, so in this
* case NULL is passed as the final argument. If you do want to force
* all images into an index/color-mapped format then you can use:
*
* PNG_IMAGE_COLORMAP_SIZE(image)
*
* to find the maximum size of the colormap in bytes.
*/
if (buffer != NULL &&
png_image_finish_read(&image, NULL/*background*/, buffer,
0/*row_stride*/, NULL/*colormap*/))
0/*row_stride*/))
{
/* Now write the image out to the second argument. In the write
* call 'convert_to_8bit' allows 16-bit data to be squashed down to
@@ -105,7 +92,7 @@ int main(int argc, const char **argv)
* to the 8-bit format.
*/
if (png_image_write_to_file(&image, argv[2], 0/*convert_to_8bit*/,
buffer, 0/*row_stride*/, NULL/*colormap*/))
buffer, 0/*row_stride*/))
{
/* The image has been written successfully. */
exit(0);
@@ -846,7 +833,7 @@ void write_png(char *file_name /* , ... other image information ... */)
/* Set the palette if there is one. REQUIRED for indexed-color images */
palette = (png_colorp)png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH
* (sizeof (png_color)));
* png_sizeof(png_color));
/* ... Set palette colors ... */
png_set_PLTE(png_ptr, info_ptr, palette, PNG_MAX_PALETTE_LENGTH);
/* You must not free palette here, because png_set_PLTE only makes a link to
@@ -877,38 +864,25 @@ void write_png(char *file_name /* , ... other image information ... */)
png_set_gAMA(png_ptr, info_ptr, gamma);
/* Optionally write comments into the image */
{
png_text text_ptr[3];
char key0[]="Title";
char text0[]="Mona Lisa";
text_ptr[0].key = key0;
text_ptr[0].text = text0;
text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[0].itxt_length = 0;
text_ptr[0].lang = NULL;
text_ptr[0].lang_key = NULL;
char key1[]="Author";
char text1[]="Leonardo DaVinci";
text_ptr[1].key = key1;
text_ptr[1].text = text1;
text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[1].itxt_length = 0;
text_ptr[1].lang = NULL;
text_ptr[1].lang_key = NULL;
char key2[]="Description";
char text2[]="<long text>";
text_ptr[2].key = key2;
text_ptr[2].text = text2;
text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
text_ptr[2].itxt_length = 0;
text_ptr[2].lang = NULL;
text_ptr[2].lang_key = NULL;
png_set_text(write_ptr, write_info_ptr, text_ptr, 3);
}
text_ptr[0].key = "Title";
text_ptr[0].text = "Mona Lisa";
text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[0].itxt_length = 0;
text_ptr[0].lang = NULL;
text_ptr[0].lang_key = NULL;
text_ptr[1].key = "Author";
text_ptr[1].text = "Leonardo DaVinci";
text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[1].itxt_length = 0;
text_ptr[1].lang = NULL;
text_ptr[1].lang_key = NULL;
text_ptr[2].key = "Description";
text_ptr[2].text = "<long text>";
text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
text_ptr[2].itxt_length = 0;
text_ptr[2].lang = NULL;
text_ptr[2].lang_key = NULL;
png_set_text(png_ptr, info_ptr, text_ptr, 3);
/* Other optional chunks like cHRM, bKGD, tRNS, tIME, oFFs, pHYs */
@@ -981,16 +955,12 @@ void write_png(char *file_name /* , ... other image information ... */)
* use the first method if you aren't handling interlacing yourself.
*/
png_uint_32 k, height, width;
/* In this example, "image" is a one-dimensional array of bytes */
png_byte image[height*width*bytes_per_pixel];
png_byte image[height][width*bytes_per_pixel];
png_bytep row_pointers[height];
if (height > PNG_UINT_32_MAX/(sizeof (png_bytep)))
if (height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
png_error (png_ptr, "Image is too tall to process in memory");
/* Set up pointers into your "image" byte array */
for (k = 0; k < height; k++)
row_pointers[k] = image + k*width*bytes_per_pixel;