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authorKarl Berry <karl@freefriends.org>2021-02-25 19:22:25 +0000
committerKarl Berry <karl@freefriends.org>2021-02-25 19:22:25 +0000
commitad547a6b5986815fda458221149728d9d9ab1d87 (patch)
tree16296910eb3eca724371474ea9aea3994dc69614 /Build/source/libs/gd/libgd-src/src/gd_png.c
parent947b43de3dd21d58ccc2ffadefc4441ea1c2a813 (diff)
restore Build,TODO from r57911
git-svn-id: svn://tug.org/texlive/trunk@57915 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/libs/gd/libgd-src/src/gd_png.c')
-rw-r--r--Build/source/libs/gd/libgd-src/src/gd_png.c1145
1 files changed, 1145 insertions, 0 deletions
diff --git a/Build/source/libs/gd/libgd-src/src/gd_png.c b/Build/source/libs/gd/libgd-src/src/gd_png.c
new file mode 100644
index 00000000000..8119cf39c05
--- /dev/null
+++ b/Build/source/libs/gd/libgd-src/src/gd_png.c
@@ -0,0 +1,1145 @@
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+#include <stdlib.h>
+#include "gd.h"
+#include "gd_errors.h"
+
+/* JCE: Arrange HAVE_LIBPNG so that it can be set in gd.h */
+#ifdef HAVE_LIBPNG
+
+#include "gdhelpers.h"
+#include "png.h" /* includes zlib.h and setjmp.h */
+
+#define TRUE 1
+#define FALSE 0
+
+/*---------------------------------------------------------------------------
+
+ gd_png.c Copyright 1999 Greg Roelofs and Thomas Boutell
+
+ The routines in this file, gdImagePng*() and gdImageCreateFromPng*(),
+ are drop-in replacements for gdImageGif*() and gdImageCreateFromGif*(),
+ except that these functions are noisier in the case of errors (comment
+ out all fprintf() statements to disable that).
+
+ GD 2.0 supports RGBA truecolor and will read and write truecolor PNGs.
+ GD 2.0 supports 8 bits of color resolution per channel and
+ 7 bits of alpha channel resolution. Images with more than 8 bits
+ per channel are reduced to 8 bits. Images with an alpha channel are
+ only able to resolve down to '1/128th opaque' instead of '1/256th',
+ and this conversion is also automatic. I very much doubt you can see it.
+ Both tRNS and true alpha are supported.
+
+ Gamma is ignored, and there is no support for text annotations.
+
+ Last updated: 9 February 2001
+
+ ---------------------------------------------------------------------------*/
+
+/**
+ * File: PNG IO
+ *
+ * Read and write PNG images.
+ */
+
+#ifdef PNG_SETJMP_SUPPORTED
+typedef struct _jmpbuf_wrapper {
+ jmp_buf jmpbuf;
+}
+jmpbuf_wrapper;
+
+static void
+gdPngErrorHandler (png_structp png_ptr, png_const_charp msg)
+{
+ jmpbuf_wrapper *jmpbuf_ptr;
+
+ /* This function, aside from the extra step of retrieving the "error
+ * pointer" (below) and the fact that it exists within the application
+ * rather than within libpng, is essentially identical to libpng's
+ * default error handler. The second point is critical: since both
+ * setjmp() and longjmp() are called from the same code, they are
+ * guaranteed to have compatible notions of how big a jmp_buf is,
+ * regardless of whether _BSD_SOURCE or anything else has (or has not)
+ * been defined. */
+
+ gd_error_ex(GD_WARNING, "gd-png: fatal libpng error: %s\n", msg);
+
+ jmpbuf_ptr = png_get_error_ptr (png_ptr);
+ if (jmpbuf_ptr == NULL) { /* we are completely hosed now */
+ gd_error_ex(GD_ERROR, "gd-png: EXTREMELY fatal error: jmpbuf unrecoverable; terminating.\n");
+ exit (99);
+ }
+
+ longjmp (jmpbuf_ptr->jmpbuf, 1);
+}
+#endif
+
+static void
+gdPngReadData (png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ int check;
+ check = gdGetBuf (data, length, (gdIOCtx *) png_get_io_ptr (png_ptr));
+ if (check != (int)length) {
+ png_error(png_ptr, "Read Error: truncated data");
+ }
+}
+
+static void
+gdPngWriteData (png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ gdPutBuf (data, length, (gdIOCtx *) png_get_io_ptr (png_ptr));
+}
+
+static void
+gdPngFlushData (png_structp png_ptr)
+{
+ (void)png_ptr;
+}
+
+/*
+ Function: gdImageCreateFromPng
+
+ <gdImageCreateFromPng> is called to load images from PNG format
+ files. Invoke <gdImageCreateFromPng> with an already opened
+ pointer to a FILE containing the desired
+ image. <gdImageCreateFromPng> returns a <gdImagePtr> to the new
+ image, or NULL if unable to load the image (most often because the
+ file is corrupt or does not contain a PNG
+ image). <gdImageCreateFromPng> does not close the file. You can
+ inspect the sx and sy members of the image to determine its
+ size. The image must eventually be destroyed using
+ gdImageDestroy().
+
+ If the PNG image being loaded is a truecolor image, the resulting
+ gdImagePtr will refer to a truecolor image. If the PNG image being
+ loaded is a palette or grayscale image, the resulting gdImagePtr
+ will refer to a palette image. gd retains only 8 bits of
+ resolution for each of the red, green and blue channels, and only
+ 7 bits of resolution for the alpha channel. The former restriction
+ affects only a handful of very rare 48-bit color and 16-bit
+ grayscale PNG images. The second restriction affects all
+ semitransparent PNG images, but the difference is essentially
+ invisible to the eye. 7 bits of alpha channel resolution is, in
+ practice, quite a lot.
+
+ Variants:
+
+ <gdImageCreateFromPngPtr> creates an image from PNG data (i.e. the
+ contents of a PNG file) already in memory.
+
+ <gdImageCreateFromPngCtx> reads in an image using the functions in
+ a <gdIOCtx> struct.
+
+ <gdImageCreateFromPngSource> is similar to
+ <gdImageCreateFromPngCtx> but uses the old <gdSource> interface.
+ It is *obsolete*.
+
+ Parameters:
+
+ infile - The input FILE pointer.
+
+ Returns:
+
+ A pointer to the new image or NULL if an error occurred.
+
+ Example:
+ (start code)
+
+ gdImagePtr im;
+ ... inside a function ...
+ FILE *in;
+ in = fopen("mypng.png", "rb");
+ im = gdImageCreateFromPng(in);
+ fclose(in);
+ // ... Use the image ...
+ gdImageDestroy(im);
+
+ (end code)
+ */
+BGD_DECLARE(gdImagePtr) gdImageCreateFromPng (FILE * inFile)
+{
+ gdImagePtr im;
+ gdIOCtx *in = gdNewFileCtx (inFile);
+ if (in == NULL) return NULL;
+ im = gdImageCreateFromPngCtx (in);
+ in->gd_free (in);
+ return im;
+}
+
+/*
+ Function: gdImageCreateFromPngPtr
+
+ See <gdImageCreateFromPng>.
+*/
+BGD_DECLARE(gdImagePtr) gdImageCreateFromPngPtr (int size, void *data)
+{
+ gdImagePtr im;
+ gdIOCtx *in = gdNewDynamicCtxEx (size, data, 0);
+ if(!in)
+ return 0;
+ im = gdImageCreateFromPngCtx (in);
+ in->gd_free (in);
+ return im;
+}
+
+
+
+/* This routine is based in part on the Chapter 13 demo code in
+ * "PNG: The Definitive Guide" (http://www.libpng.org/pub/png/book/).
+ */
+
+/*
+ Function: gdImageCreateFromPngCtx
+
+ See <gdImageCreateFromPng>.
+*/
+BGD_DECLARE(gdImagePtr) gdImageCreateFromPngCtx (gdIOCtx * infile)
+{
+ png_byte sig[8];
+#ifdef PNG_SETJMP_SUPPORTED
+ jmpbuf_wrapper jbw;
+#endif
+ png_structp png_ptr;
+ png_infop info_ptr;
+ png_uint_32 width, height, rowbytes, w, h, res_x, res_y;
+ int bit_depth, color_type, interlace_type, unit_type;
+ int num_palette = 0, num_trans;
+ png_colorp palette;
+ png_color_16p trans_gray_rgb;
+ png_color_16p trans_color_rgb;
+ png_bytep trans;
+ png_bytep image_data = NULL;
+ png_bytepp row_pointers = NULL;
+ gdImagePtr im = NULL;
+ int i, j, *open = NULL;
+ volatile int transparent = -1;
+ volatile int palette_allocated = FALSE;
+
+ /* Make sure the signature can't match by dumb luck -- TBB */
+ /* GRR: isn't sizeof(infile) equal to the size of the pointer? */
+ memset (sig, 0, sizeof (sig));
+
+ /* first do a quick check that the file really is a PNG image; could
+ * have used slightly more general png_sig_cmp() function instead */
+ if (gdGetBuf (sig, 8, infile) < 8) {
+ return NULL;
+ }
+
+ if (png_sig_cmp(sig, 0, 8) != 0) { /* bad signature */
+ return NULL; /* bad signature */
+ }
+
+#ifdef PNG_SETJMP_SUPPORTED
+ png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, &jbw, gdPngErrorHandler, NULL);
+#else
+ png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+#endif
+ if (png_ptr == NULL) {
+ gd_error("gd-png error: cannot allocate libpng main struct\n");
+ return NULL;
+ }
+
+ info_ptr = png_create_info_struct (png_ptr);
+ if (info_ptr == NULL) {
+ gd_error("gd-png error: cannot allocate libpng info struct\n");
+ png_destroy_read_struct (&png_ptr, NULL, NULL);
+
+ return NULL;
+ }
+
+ /* we could create a second info struct here (end_info), but it's only
+ * useful if we want to keep pre- and post-IDAT chunk info separated
+ * (mainly for PNG-aware image editors and converters)
+ */
+
+ /* setjmp() must be called in every non-callback function that calls a
+ * PNG-reading libpng function. We must reset it everytime we get a
+ * new allocation that we save in a stack variable.
+ */
+#ifdef PNG_SETJMP_SUPPORTED
+ if (setjmp(jbw.jmpbuf)) {
+ gd_error("gd-png error: setjmp returns error condition 1\n");
+ png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+
+ return NULL;
+ }
+#endif
+
+ png_set_sig_bytes (png_ptr, 8); /* we already read the 8 signature bytes */
+
+ png_set_read_fn (png_ptr, (void *) infile, gdPngReadData);
+ png_read_info (png_ptr, info_ptr); /* read all PNG info up to image data */
+
+ png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL);
+ if ((color_type == PNG_COLOR_TYPE_RGB) || (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+ || color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
+ im = gdImageCreateTrueColor ((int) width, (int) height);
+ } else {
+ im = gdImageCreate ((int) width, (int) height);
+ }
+ if (im == NULL) {
+ gd_error("gd-png error: cannot allocate gdImage struct\n");
+ goto error;
+ }
+
+ if (bit_depth == 16) {
+ png_set_strip_16 (png_ptr);
+ } else if (bit_depth < 8) {
+ png_set_packing (png_ptr); /* expand to 1 byte per pixel */
+ }
+
+ /* setjmp() must be called in every non-callback function that calls a
+ * PNG-reading libpng function. We must reset it everytime we get a
+ * new allocation that we save in a stack variable.
+ */
+#ifdef PNG_SETJMP_SUPPORTED
+ if (setjmp(jbw.jmpbuf)) {
+ gd_error("gd-png error: setjmp returns error condition 2\n");
+ goto error;
+ }
+#endif
+
+#ifdef PNG_pHYs_SUPPORTED
+ /* check if the resolution is specified */
+ if (png_get_valid(png_ptr, info_ptr, PNG_INFO_pHYs)) {
+ if (png_get_pHYs(png_ptr, info_ptr, &res_x, &res_y, &unit_type)) {
+ switch (unit_type) {
+ case PNG_RESOLUTION_METER:
+ im->res_x = DPM2DPI(res_x);
+ im->res_y = DPM2DPI(res_y);
+ break;
+ }
+ }
+ }
+#endif
+
+ switch (color_type) {
+ case PNG_COLOR_TYPE_PALETTE:
+ png_get_PLTE (png_ptr, info_ptr, &palette, &num_palette);
+#ifdef DEBUG
+ gd_error("gd-png color_type is palette, colors: %d\n", num_palette);
+#endif /* DEBUG */
+ if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS)) {
+ /* gd 2.0: we support this rather thoroughly now. Grab the
+ * first fully transparent entry, if any, as the value of
+ * the simple-transparency index, mostly for backwards
+ * binary compatibility. The alpha channel is where it's
+ * really at these days.
+ */
+ int firstZero = 1;
+ png_get_tRNS (png_ptr, info_ptr, &trans, &num_trans, NULL);
+ for (i = 0; i < num_trans; ++i) {
+ im->alpha[i] = gdAlphaMax - (trans[i] >> 1);
+ if ((trans[i] == 0) && (firstZero)) {
+ /* 2.0.5: long-forgotten patch from Wez Furlong */
+ transparent = i;
+ firstZero = 0;
+ }
+ }
+ }
+ break;
+
+ case PNG_COLOR_TYPE_GRAY:
+ /* create a fake palette and check for single-shade transparency */
+ if ((palette = (png_colorp) gdMalloc (256 * sizeof (png_color))) == NULL) {
+ gd_error("gd-png error: cannot allocate gray palette\n");
+ goto error;
+ }
+ palette_allocated = TRUE;
+ if (bit_depth < 8) {
+ num_palette = 1 << bit_depth;
+ for (i = 0; i < 256; ++i) {
+ j = (255 * i) / (num_palette - 1);
+ palette[i].red = palette[i].green = palette[i].blue = j;
+ }
+ } else {
+ num_palette = 256;
+ for (i = 0; i < 256; ++i) {
+ palette[i].red = palette[i].green = palette[i].blue = i;
+ }
+ }
+ if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS)) {
+ png_get_tRNS (png_ptr, info_ptr, NULL, NULL, &trans_gray_rgb);
+ if (bit_depth == 16) { /* png_set_strip_16() not yet in effect */
+ transparent = trans_gray_rgb->gray >> 8;
+ } else {
+ transparent = trans_gray_rgb->gray;
+ }
+ /* Note slight error in 16-bit case: up to 256 16-bit shades
+ * may get mapped to a single 8-bit shade, and only one of them
+ * is supposed to be transparent. IOW, both opaque pixels and
+ * transparent pixels will be mapped into the transparent entry.
+ * There is no particularly good way around this in the case
+ * that all 256 8-bit shades are used, but one could write some
+ * custom 16-bit code to handle the case where there are gdFree
+ * palette entries. This error will be extremely rare in
+ * general, though. (Quite possibly there is only one such
+ * image in existence.) */
+ }
+ break;
+
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ png_set_gray_to_rgb(png_ptr);
+
+ case PNG_COLOR_TYPE_RGB:
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ /* gd 2.0: we now support truecolor. See the comment above
+ for a rare situation in which the transparent pixel may not
+ work properly with 16-bit channels. */
+ if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS)) {
+ png_get_tRNS (png_ptr, info_ptr, NULL, NULL, &trans_color_rgb);
+ if (bit_depth == 16) { /* png_set_strip_16() not yet in effect */
+ transparent = gdTrueColor (trans_color_rgb->red >> 8,
+ trans_color_rgb->green >> 8,
+ trans_color_rgb->blue >> 8);
+ } else {
+ transparent = gdTrueColor (trans_color_rgb->red,
+ trans_color_rgb->green,
+ trans_color_rgb->blue);
+ }
+ }
+ break;
+ default:
+ gd_error("gd-png color_type is unknown: %d\n", color_type);
+ goto error;
+ }
+
+ png_read_update_info (png_ptr, info_ptr);
+
+ /* allocate space for the PNG image data */
+ rowbytes = png_get_rowbytes (png_ptr, info_ptr);
+ if (overflow2(rowbytes, height))
+ goto error;
+ image_data = (png_bytep) gdMalloc (rowbytes * height);
+ if (!image_data) {
+ gd_error("gd-png error: cannot allocate image data\n");
+ goto error;
+ }
+ if (overflow2(height, sizeof (png_bytep)))
+ goto error;
+
+ row_pointers = (png_bytepp) gdMalloc (height * sizeof (png_bytep));
+ if (!row_pointers) {
+ gd_error("gd-png error: cannot allocate row pointers\n");
+ goto error;
+ }
+
+ /* setjmp() must be called in every non-callback function that calls a
+ * PNG-reading libpng function. We must reset it everytime we get a
+ * new allocation that we save in a stack variable.
+ */
+#ifdef PNG_SETJMP_SUPPORTED
+ if (setjmp(jbw.jmpbuf)) {
+ gd_error("gd-png error: setjmp returns error condition 3\n");
+ goto error;
+ }
+#endif
+
+ /* set the individual row_pointers to point at the correct offsets */
+ for (h = 0; h < height; ++h) {
+ row_pointers[h] = image_data + h * rowbytes;
+ }
+
+ png_read_image (png_ptr, row_pointers); /* read whole image... */
+ png_read_end (png_ptr, NULL); /* ...done! */
+
+ if (!im->trueColor) {
+ im->colorsTotal = num_palette;
+ /* load the palette and mark all entries "open" (unused) for now */
+ open = im->open;
+ for (i = 0; i < num_palette; ++i) {
+ im->red[i] = palette[i].red;
+ im->green[i] = palette[i].green;
+ im->blue[i] = palette[i].blue;
+ open[i] = 1;
+ }
+ for (i = num_palette; i < gdMaxColors; ++i) {
+ open[i] = 1;
+ }
+ }
+ /* 2.0.12: Slaven Rezic: palette images are not the only images
+ with a simple transparent color setting */
+ im->transparent = transparent;
+ im->interlace = (interlace_type == PNG_INTERLACE_ADAM7);
+
+ /* can't nuke structs until done with palette */
+ png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+ switch (color_type) {
+ case PNG_COLOR_TYPE_RGB:
+ for (h = 0; h < height; h++) {
+ int boffset = 0;
+ for (w = 0; w < width; w++) {
+ register png_byte r = row_pointers[h][boffset++];
+ register png_byte g = row_pointers[h][boffset++];
+ register png_byte b = row_pointers[h][boffset++];
+ im->tpixels[h][w] = gdTrueColor (r, g, b);
+ }
+ }
+ break;
+
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ for (h = 0; h < height; h++) {
+ int boffset = 0;
+ for (w = 0; w < width; w++) {
+ register png_byte r = row_pointers[h][boffset++];
+ register png_byte g = row_pointers[h][boffset++];
+ register png_byte b = row_pointers[h][boffset++];
+
+ /* gd has only 7 bits of alpha channel resolution, and
+ * 127 is transparent, 0 opaque. A moment of convenience,
+ * a lifetime of compatibility.
+ */
+
+ register png_byte a = gdAlphaMax - (row_pointers[h][boffset++] >> 1);
+ im->tpixels[h][w] = gdTrueColorAlpha(r, g, b, a);
+ }
+ }
+ break;
+ default:
+ if (!im->trueColor) {
+ /* Palette image, or something coerced to be one */
+ for (h = 0; h < height; ++h) {
+ for (w = 0; w < width; ++w) {
+ register png_byte idx = row_pointers[h][w];
+ im->pixels[h][w] = idx;
+ open[idx] = 0;
+ }
+ }
+ }
+ }
+#ifdef DEBUG
+ if (!im->trueColor) {
+ for (i = num_palette; i < gdMaxColors; ++i) {
+ if (!open[i]) {
+ fprintf (stderr,
+ "gd-png warning: image data references out-of-range"
+ " color index (%d)\n", i);
+ }
+ }
+ }
+#endif
+
+ done:
+ if (palette_allocated) {
+ gdFree (palette);
+ }
+ if (image_data)
+ gdFree(image_data);
+ if (row_pointers)
+ gdFree(row_pointers);
+
+ return im;
+
+ error:
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ if (im) {
+ gdImageDestroy(im);
+ im = NULL;
+ }
+ goto done;
+}
+
+
+/*
+ Function: gdImagePngEx
+
+ <gdImagePngEx> outputs the specified image to the specified file in
+ PNG format. The file must be open for writing. Under MSDOS and all
+ versions of Windows, it is important to use "wb" as opposed to
+ simply "w" as the mode when opening the file, and under Unix there
+ is no penalty for doing so. <gdImagePngEx> does not close the file;
+ your code must do so.
+
+ In addition, <gdImagePngEx> allows the level of compression to be
+ specified. A compression level of 0 means "no compression." A
+ compression level of 1 means "compressed, but as quickly as
+ possible." A compression level of 9 means "compressed as much as
+ possible to produce the smallest possible file." A compression level
+ of -1 will use the default compression level at the time zlib was
+ compiled on your system.
+
+ Variants:
+
+ <gdImagePng> is equivalent to calling <gdImagePngEx> with
+ compression of -1.
+
+ <gdImagePngCtx> and <gdImagePngCtxEx> write via a <gdIOCtx>
+ instead of a file handle.
+
+ <gdImagePngPtr> and <gdImagePngPtrEx> store the image file to
+ memory.
+
+ Parameters:
+
+ im - the image to write
+ outFile - the output FILE* object.
+ level - compression level: 0 -> none, 1-9 -> level, -1 -> default
+
+ Returns:
+
+ Nothing.
+
+ Example:
+ (start code)
+
+ gdImagePtr im;
+ int black, white;
+ FILE *out;
+
+ im = gdImageCreate(100, 100); // Create the image
+ white = gdImageColorAllocate(im, 255, 255, 255); // Alloc background
+ black = gdImageColorAllocate(im, 0, 0, 0); // Allocate drawing color
+ gdImageRectangle(im, 0, 0, 99, 99, black); // Draw rectangle
+ out = fopen("rect.png", "wb"); // Open output file (binary)
+ gdImagePngEx(im, out, 9); // Write PNG, max compression
+ fclose(out); // Close file
+ gdImageDestroy(im); // Destroy image
+
+ (end code)
+*/
+BGD_DECLARE(void) gdImagePngEx (gdImagePtr im, FILE * outFile, int level)
+{
+ gdIOCtx *out = gdNewFileCtx (outFile);
+ if (out == NULL) return;
+ gdImagePngCtxEx (im, out, level);
+ out->gd_free (out);
+}
+
+/*
+ Function: gdImagePng
+
+ Equivalent to calling <gdImagePngEx> with compression of -1.
+
+ Parameters:
+
+ im - the image to save.
+ outFile - the output FILE*.
+
+ Returns:
+
+ Nothing.
+*/
+BGD_DECLARE(void) gdImagePng (gdImagePtr im, FILE * outFile)
+{
+ gdIOCtx *out = gdNewFileCtx (outFile);
+ if (out == NULL) return;
+ gdImagePngCtxEx (im, out, -1);
+ out->gd_free (out);
+}
+
+static int _gdImagePngCtxEx(gdImagePtr im, gdIOCtx * outfile, int level);
+
+/*
+ Function: gdImagePngPtr
+
+ Equivalent to calling <gdImagePngPtrEx> with compression of -1.
+
+ See <gdImagePngEx> for more information.
+
+ Parameters:
+
+ im - the image to save.
+ size - Output: size in bytes of the result.
+
+ Returns:
+
+ A pointer to memory containing the image data or NULL on error.
+
+*/
+BGD_DECLARE(void *) gdImagePngPtr (gdImagePtr im, int *size)
+{
+ void *rv;
+ gdIOCtx *out = gdNewDynamicCtx (2048, NULL);
+ if (out == NULL) return NULL;
+ if (!_gdImagePngCtxEx (im, out, -1)) {
+ rv = gdDPExtractData (out, size);
+ } else {
+ rv = NULL;
+ }
+ out->gd_free (out);
+ return rv;
+}
+
+/*
+ Function: gdImagePngPtrEx
+
+ Identical to <gdImagePngEx> except that it returns a pointer to a
+ memory area with the PNG data. This memory must be freed by the
+ caller when it is no longer needed. **The caller must invoke
+ gdFree(), not free()**
+
+ The 'size' parameter receives the total size of the block of
+ memory.
+
+ See <gdImagePngEx> for more information.
+
+ Parameters:
+
+ im - the image to save.
+ size - Output: size in bytes of the result.
+ level - compression level: 0 -> none, 1-9 -> level, -1 -> default
+
+ Returns:
+
+ A pointer to memory containing the image data or NULL on error.
+
+*/
+BGD_DECLARE(void *) gdImagePngPtrEx (gdImagePtr im, int *size, int level)
+{
+ void *rv;
+ gdIOCtx *out = gdNewDynamicCtx (2048, NULL);
+ if (out == NULL) return NULL;
+ if (!_gdImagePngCtxEx (im, out, level)) {
+ rv = gdDPExtractData (out, size);
+ } else {
+ rv = NULL;
+ }
+ out->gd_free (out);
+ return rv;
+}
+
+
+
+/*
+ Function: gdImagePngCtx
+
+ Equivalent to calling <gdImagePngCtxEx> with compression of -1.
+ See <gdImagePngEx> for more information.
+
+ Parameters:
+
+ im - the image to save.
+ outfile - the <gdIOCtx> to write to.
+
+ Returns:
+
+ Nothing.
+
+*/
+BGD_DECLARE(void) gdImagePngCtx (gdImagePtr im, gdIOCtx * outfile)
+{
+ /* 2.0.13: 'return' here was an error, thanks to Kevin Smith */
+ gdImagePngCtxEx (im, outfile, -1);
+}
+
+
+
+
+/*
+ Function: gdImagePngCtxEx
+
+ Outputs the given image as PNG data, but using a <gdIOCtx> instead
+ of a file. See <gdIamgePnEx>.
+
+ Parameters:
+
+ im - the image to save.
+ outfile - the <gdIOCtx> to write to.
+ level - compression level: 0 -> none, 1-9 -> level, -1 -> default
+
+ Returns:
+
+ Nothing.
+
+*/
+BGD_DECLARE(void) gdImagePngCtxEx (gdImagePtr im, gdIOCtx * outfile, int level)
+{
+ _gdImagePngCtxEx(im, outfile, level);
+}
+
+/* This routine is based in part on code from Dale Lutz (Safe Software Inc.)
+ * and in part on demo code from Chapter 15 of "PNG: The Definitive Guide"
+ * (http://www.libpng.org/pub/png/book/).
+ */
+/* returns 0 on success, 1 on failure */
+static int _gdImagePngCtxEx(gdImagePtr im, gdIOCtx * outfile, int level)
+{
+ int i, j, bit_depth = 0, interlace_type;
+ int width = im->sx;
+ int height = im->sy;
+ int colors = im->colorsTotal;
+ int *open = im->open;
+ int mapping[gdMaxColors]; /* mapping[gd_index] == png_index */
+ png_byte trans_values[256];
+ png_color_16 trans_rgb_value;
+ png_color palette[gdMaxColors];
+ png_structp png_ptr;
+ png_infop info_ptr;
+ png_bytep *row_pointers = NULL;
+ volatile int transparent = im->transparent;
+ volatile int remap = FALSE;
+#ifdef PNG_SETJMP_SUPPORTED
+ jmpbuf_wrapper jbw;
+#endif
+ int ret = 0;
+
+ /* width or height of value 0 is invalid in IHDR;
+ see http://www.w3.org/TR/PNG-Chunks.html */
+ if (width == 0 || height ==0) return 1;
+
+#ifdef PNG_SETJMP_SUPPORTED
+ png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING,
+ &jbw, gdPngErrorHandler,
+ NULL);
+#else
+ png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+#endif
+ if (png_ptr == NULL) {
+ gd_error("gd-png error: cannot allocate libpng main struct\n");
+ return 1;
+ }
+
+ info_ptr = png_create_info_struct (png_ptr);
+ if (info_ptr == NULL) {
+ gd_error("gd-png error: cannot allocate libpng info struct\n");
+ png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+ return 1;
+ }
+
+#ifdef PNG_SETJMP_SUPPORTED
+ if (setjmp(jbw.jmpbuf)) {
+ gd_error("gd-png error: setjmp returns error condition\n");
+ png_destroy_write_struct (&png_ptr, &info_ptr);
+
+ if (row_pointers) {
+ for (i = 0; i < height; ++i)
+ gdFree(row_pointers[i]);
+ gdFree(row_pointers);
+ }
+
+ return 1;
+ }
+#endif
+
+ png_set_write_fn (png_ptr, (void *) outfile, gdPngWriteData,
+ gdPngFlushData);
+
+ /* This is best for palette images, and libpng defaults to it for
+ palette images anyway, so we don't need to do it explicitly.
+ What to ideally do for truecolor images depends, alas, on the image.
+ gd is intentionally imperfect and doesn't spend a lot of time
+ fussing with such things. */
+
+ /* Faster if this is uncommented, but may produce larger truecolor files.
+ Wait for gdImagePngCtxEx. */
+#if 0
+ png_set_filter (png_ptr, 0, PNG_FILTER_NONE);
+#endif
+
+ /* 2.0.12: this is finally a parameter */
+ png_set_compression_level (png_ptr, level);
+
+#ifdef PNG_pHYs_SUPPORTED
+ /* 2.1.0: specify the resolution */
+ png_set_pHYs(png_ptr, info_ptr, DPI2DPM(im->res_x), DPI2DPM(im->res_y),
+ PNG_RESOLUTION_METER);
+#endif
+
+ /* can set this to a smaller value without compromising compression if all
+ * image data is 16K or less; will save some decoder memory [min == 8] */
+ /* png_set_compression_window_bits(png_ptr, 15); */
+
+ if (!im->trueColor) {
+ if (transparent >= im->colorsTotal ||
+ (transparent >= 0 && open[transparent]))
+ transparent = -1;
+ }
+ if (!im->trueColor) {
+ for (i = 0; i < gdMaxColors; ++i)
+ mapping[i] = -1;
+ }
+ if (!im->trueColor) {
+ /* count actual number of colors used (colorsTotal == high-water mark) */
+ colors = 0;
+ for (i = 0; i < im->colorsTotal; ++i) {
+ if (!open[i]) {
+ mapping[i] = colors;
+ ++colors;
+ }
+ }
+ if (colors == 0) {
+ gd_error("gd-png error: no colors in palette\n");
+ ret = 1;
+ goto bail;
+ }
+ if (colors < im->colorsTotal) {
+ remap = TRUE;
+ }
+ if (colors <= 2)
+ bit_depth = 1;
+ else if (colors <= 4)
+ bit_depth = 2;
+ else if (colors <= 16)
+ bit_depth = 4;
+ else
+ bit_depth = 8;
+ }
+ interlace_type = im->interlace ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE;
+
+ if (im->trueColor) {
+ if (im->saveAlphaFlag) {
+ png_set_IHDR (png_ptr, info_ptr, width, height, 8,
+ PNG_COLOR_TYPE_RGB_ALPHA, interlace_type,
+ PNG_COMPRESSION_TYPE_DEFAULT,
+ PNG_FILTER_TYPE_DEFAULT);
+ } else {
+ png_set_IHDR (png_ptr, info_ptr, width, height, 8,
+ PNG_COLOR_TYPE_RGB, interlace_type,
+ PNG_COMPRESSION_TYPE_DEFAULT,
+ PNG_FILTER_TYPE_DEFAULT);
+ }
+ } else {
+ png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth,
+ PNG_COLOR_TYPE_PALETTE, interlace_type,
+ PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+ }
+ if (im->trueColor && (!im->saveAlphaFlag) && (transparent >= 0)) {
+ /* 2.0.9: fixed by Thomas Winzig */
+ trans_rgb_value.red = gdTrueColorGetRed (im->transparent);
+ trans_rgb_value.green = gdTrueColorGetGreen (im->transparent);
+ trans_rgb_value.blue = gdTrueColorGetBlue (im->transparent);
+ png_set_tRNS (png_ptr, info_ptr, 0, 0, &trans_rgb_value);
+ }
+ if (!im->trueColor) {
+ /* Oy veh. Remap the PNG palette to put the
+ entries with interesting alpha channel
+ values first. This minimizes the size
+ of the tRNS chunk and thus the size
+ of the PNG file as a whole. */
+ int tc = 0;
+ int i;
+ int j;
+ int k;
+ for (i = 0; (i < im->colorsTotal); i++) {
+ if ((!im->open[i]) && (im->alpha[i] != gdAlphaOpaque)) {
+ tc++;
+ }
+ }
+ if (tc) {
+#if 0
+ for (i = 0; (i < im->colorsTotal); i++) {
+ trans_values[i] = 255 -
+ ((im->alpha[i] << 1) + (im->alpha[i] >> 6));
+ }
+ png_set_tRNS (png_ptr, info_ptr, trans_values, 256, NULL);
+#endif
+ if (!remap) {
+ remap = TRUE;
+ }
+ /* (Semi-)transparent indexes come up from the bottom
+ of the list of real colors; opaque
+ indexes come down from the top */
+ j = 0;
+ k = colors - 1;
+ for (i = 0; (i < im->colorsTotal); i++) {
+ if (!im->open[i]) {
+ if (im->alpha[i] != gdAlphaOpaque) {
+ /* Andrew Hull: >> 6, not >> 7! (gd 2.0.5) */
+ trans_values[j] = 255 -
+ ((im->alpha[i] << 1) + (im->alpha[i] >> 6));
+ mapping[i] = j++;
+ } else {
+ mapping[i] = k--;
+ }
+ }
+ }
+ png_set_tRNS (png_ptr, info_ptr, trans_values, tc, NULL);
+ }
+ }
+
+ /* convert palette to libpng layout */
+ if (!im->trueColor) {
+ if (remap)
+ for (i = 0; i < im->colorsTotal; ++i) {
+ if (mapping[i] < 0)
+ continue;
+ palette[mapping[i]].red = im->red[i];
+ palette[mapping[i]].green = im->green[i];
+ palette[mapping[i]].blue = im->blue[i];
+ }
+ else
+ for (i = 0; i < colors; ++i) {
+ palette[i].red = im->red[i];
+ palette[i].green = im->green[i];
+ palette[i].blue = im->blue[i];
+ }
+ png_set_PLTE (png_ptr, info_ptr, palette, colors);
+ }
+
+ /* write out the PNG header info (everything up to first IDAT) */
+ png_write_info (png_ptr, info_ptr);
+
+ /* make sure < 8-bit images are packed into pixels as tightly as possible */
+ png_set_packing (png_ptr);
+
+ /* This code allocates a set of row buffers and copies the gd image data
+ * into them only in the case that remapping is necessary; in gd 1.3 and
+ * later, the im->pixels array is laid out identically to libpng's row
+ * pointers and can be passed to png_write_image() function directly.
+ * The remapping case could be accomplished with less memory for non-
+ * interlaced images, but interlacing causes some serious complications. */
+ if (im->trueColor) {
+ /* performance optimizations by Phong Tran */
+ int channels = im->saveAlphaFlag ? 4 : 3;
+ /* Our little 7-bit alpha channel trick costs us a bit here. */
+ unsigned char *pOutputRow;
+ int **ptpixels = im->tpixels;
+ int *pThisRow;
+ unsigned char a;
+ int thisPixel;
+ png_bytep *prow_pointers;
+ int saveAlphaFlag = im->saveAlphaFlag;
+ if (overflow2(sizeof (png_bytep), height)) {
+ ret = 1;
+ goto bail;
+ }
+ /* Need to use calloc so we can clean it up sanely in the error handler. */
+ row_pointers = gdCalloc(height, sizeof (png_bytep));
+ if (row_pointers == NULL) {
+ gd_error("gd-png error: unable to allocate row_pointers\n");
+ ret = 1;
+ goto bail;
+ }
+ prow_pointers = row_pointers;
+ for (j = 0; j < height; ++j) {
+ if (overflow2(width, channels) || ((*prow_pointers =
+ (png_bytep) gdMalloc (width * channels)) == NULL)) {
+ gd_error("gd-png error: unable to allocate rows\n");
+ for (i = 0; i < j; ++i)
+ gdFree (row_pointers[i]);
+ /* 2.0.29: memory leak TBB */
+ gdFree(row_pointers);
+ ret = 1;
+ goto bail;
+ }
+ pOutputRow = *prow_pointers++;
+ pThisRow = *ptpixels++;
+ for (i = 0; i < width; ++i) {
+ thisPixel = *pThisRow++;
+ *pOutputRow++ = gdTrueColorGetRed (thisPixel);
+ *pOutputRow++ = gdTrueColorGetGreen (thisPixel);
+ *pOutputRow++ = gdTrueColorGetBlue (thisPixel);
+
+ if (saveAlphaFlag) {
+ /* convert the 7-bit alpha channel to an 8-bit alpha channel.
+ We do a little bit-flipping magic, repeating the MSB
+ as the LSB, to ensure that 0 maps to 0 and
+ 127 maps to 255. We also have to invert to match
+ PNG's convention in which 255 is opaque. */
+ a = gdTrueColorGetAlpha (thisPixel);
+ /* Andrew Hull: >> 6, not >> 7! (gd 2.0.5) */
+ *pOutputRow++ = 255 - ((a << 1) + (a >> 6));
+ }
+ }
+ }
+
+ png_write_image (png_ptr, row_pointers);
+ png_write_end (png_ptr, info_ptr);
+
+ for (j = 0; j < height; ++j)
+ gdFree (row_pointers[j]);
+ gdFree (row_pointers);
+ } else {
+ if (remap) {
+ png_bytep *row_pointers;
+ if (overflow2(sizeof (png_bytep), height)) {
+ ret = 1;
+ goto bail;
+ }
+ row_pointers = gdMalloc (sizeof (png_bytep) * height);
+ if (row_pointers == NULL) {
+ gd_error("gd-png error: unable to allocate row_pointers\n");
+ ret = 1;
+ goto bail;
+ }
+ for (j = 0; j < height; ++j) {
+ if ((row_pointers[j] = (png_bytep) gdMalloc (width)) == NULL) {
+ gd_error("gd-png error: unable to allocate rows\n");
+ for (i = 0; i < j; ++i)
+ gdFree (row_pointers[i]);
+ /* TBB: memory leak */
+ gdFree (row_pointers);
+ ret = 1;
+ goto bail;
+ }
+ for (i = 0; i < width; ++i)
+ row_pointers[j][i] = mapping[im->pixels[j][i]];
+ }
+
+ png_write_image (png_ptr, row_pointers);
+ png_write_end (png_ptr, info_ptr);
+
+ for (j = 0; j < height; ++j)
+ gdFree (row_pointers[j]);
+ gdFree (row_pointers);
+ } else {
+ png_write_image (png_ptr, im->pixels);
+ png_write_end (png_ptr, info_ptr);
+ }
+ }
+ /* 1.6.3: maybe we should give that memory BACK! TBB */
+bail:
+ png_destroy_write_struct (&png_ptr, &info_ptr);
+ return ret;
+}
+
+#else /* !HAVE_LIBPNG */
+
+static void _noPngError(void)
+{
+ gd_error("PNG image support has been disabled\n");
+}
+
+BGD_DECLARE(gdImagePtr) gdImageCreateFromPng (FILE * inFile)
+{
+ _noPngError();
+ return NULL;
+}
+
+BGD_DECLARE(gdImagePtr) gdImageCreateFromPngPtr (int size, void *data)
+{
+ return NULL;
+}
+
+BGD_DECLARE(gdImagePtr) gdImageCreateFromPngCtx (gdIOCtx * infile)
+{
+ return NULL;
+}
+
+BGD_DECLARE(void) gdImagePngEx (gdImagePtr im, FILE * outFile, int level)
+{
+ _noPngError();
+}
+
+BGD_DECLARE(void) gdImagePng (gdImagePtr im, FILE * outFile)
+{
+ _noPngError();
+}
+
+BGD_DECLARE(void *) gdImagePngPtr (gdImagePtr im, int *size)
+{
+ return NULL;
+}
+
+BGD_DECLARE(void *) gdImagePngPtrEx (gdImagePtr im, int *size, int level)
+{
+ return NULL;
+}
+
+BGD_DECLARE(void) gdImagePngCtx (gdImagePtr im, gdIOCtx * outfile)
+{
+ _noPngError();
+}
+
+BGD_DECLARE(void) gdImagePngCtxEx (gdImagePtr im, gdIOCtx * outfile, int level)
+{
+ _noPngError();
+}
+
+#endif /* HAVE_LIBPNG */