#include "impng.h"
#include "png.h"
+#include <stdlib.h>
/* this is a way to get number of channels from color space
* Color code to channel number */
static i_img *
read_bilevel(png_structp png_ptr, png_infop info_ptr, i_img_dim width, i_img_dim height);
+static int
+write_direct8(png_structp png_ptr, png_infop info_ptr, i_img *im);
+
+static int
+write_direct16(png_structp png_ptr, png_infop info_ptr, i_img *im);
+
+static int
+write_paletted(png_structp png_ptr, png_infop info_ptr, i_img *im, int bits);
+
+static int
+write_bilevel(png_structp png_ptr, png_infop info_ptr, i_img *im);
+
+static void
+get_png_tags(i_img *im, png_structp png_ptr, png_infop info_ptr, int bit_depth, int color_type);
+
+static int
+set_png_tags(i_img *im, png_structp png_ptr, png_infop info_ptr);
+
+static const char *
+get_string2(i_img_tags *tags, const char *name, char *buf, size_t *size);
+
unsigned
i_png_lib_version(void) {
return png_access_version_number();
static void
wiol_flush_data(png_structp png_ptr) {
- /* XXX : This needs to be added to the io layer */
+ io_glue *ig = png_get_io_ptr(png_ptr);
+ if (!i_io_flush(ig))
+ png_error(png_ptr, "Error flushing output");
}
static void
i_writepng_wiol(i_img *im, io_glue *ig) {
png_structp png_ptr;
png_infop info_ptr = NULL;
- i_img_dim width,height,y;
+ i_img_dim width,height;
volatile int cspace,channels;
- double xres, yres;
- int aspect_only, have_res;
- unsigned char *data;
- unsigned char * volatile vdata = NULL;
+ int bits;
+ int is_bilevel = 0, zero_is_white;
mm_log((1,"i_writepng(im %p ,ig %p)\n", im, ig));
channels=im->channels;
- if (channels > 2) { cspace = PNG_COLOR_TYPE_RGB; channels-=3; }
- else { cspace=PNG_COLOR_TYPE_GRAY; channels--; }
-
- if (channels) cspace|=PNG_COLOR_MASK_ALPHA;
- mm_log((1,"cspace=%d\n",cspace));
+ if (i_img_is_monochrome(im, &zero_is_white)) {
+ is_bilevel = 1;
+ bits = 1;
+ cspace = PNG_COLOR_TYPE_GRAY;
+ mm_log((1, "i_writepng: bilevel output\n"));
+ }
+ else if (im->type == i_palette_type) {
+ int colors = i_colorcount(im);
- channels = im->channels;
+ cspace = PNG_COLOR_TYPE_PALETTE;
+ bits = 1;
+ while ((1 << bits) < colors) {
+ bits += bits;
+ }
+ mm_log((1, "i_writepng: paletted output\n"));
+ }
+ else {
+ switch (channels) {
+ case 1:
+ cspace = PNG_COLOR_TYPE_GRAY;
+ break;
+ case 2:
+ cspace = PNG_COLOR_TYPE_GRAY_ALPHA;
+ break;
+ case 3:
+ cspace = PNG_COLOR_TYPE_RGB;
+ break;
+ case 4:
+ cspace = PNG_COLOR_TYPE_RGB_ALPHA;
+ break;
+ default:
+ fprintf(stderr, "Internal error, channels = %d\n", channels);
+ abort();
+ }
+ bits = im->bits > 8 ? 16 : 8;
+ mm_log((1, "i_writepng: direct output\n"));
+ }
+
+ mm_log((1,"i_writepng: cspace=%d, bits=%d\n",cspace, bits));
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
*/
if (setjmp(png_jmpbuf(png_ptr))) {
png_destroy_write_struct(&png_ptr, &info_ptr);
- if (vdata)
- myfree(vdata);
return(0);
}
*/
png_set_user_limits(png_ptr, width, height);
- png_set_IHDR(png_ptr, info_ptr, width, height, 8, cspace,
+ png_set_IHDR(png_ptr, info_ptr, width, height, bits, cspace,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
- have_res = 1;
- if (i_tags_get_float(&im->tags, "i_xres", 0, &xres)) {
- if (i_tags_get_float(&im->tags, "i_yres", 0, &yres))
- ; /* nothing to do */
- else
- yres = xres;
+ if (!set_png_tags(im, png_ptr, info_ptr)) {
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ return 0;
}
- else {
- if (i_tags_get_float(&im->tags, "i_yres", 0, &yres))
- xres = yres;
- else
- have_res = 0;
+
+ if (is_bilevel) {
+ if (!write_bilevel(png_ptr, info_ptr, im)) {
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ return 0;
+ }
}
- if (have_res) {
- aspect_only = 0;
- i_tags_get_int(&im->tags, "i_aspect_only", 0, &aspect_only);
- xres /= 0.0254;
- yres /= 0.0254;
- png_set_pHYs(png_ptr, info_ptr, xres + 0.5, yres + 0.5,
- aspect_only ? PNG_RESOLUTION_UNKNOWN : PNG_RESOLUTION_METER);
+ else if (im->type == i_palette_type) {
+ if (!write_paletted(png_ptr, info_ptr, im, bits)) {
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ return 0;
+ }
}
-
- png_write_info(png_ptr, info_ptr);
-
- vdata = data = mymalloc(im->xsize * im->channels);
- for (y = 0; y < height; y++) {
- i_gsamp(im, 0, im->xsize, y, data, NULL, im->channels);
- png_write_row(png_ptr, (png_bytep)data);
+ else if (bits == 16) {
+ if (!write_direct16(png_ptr, info_ptr, im)) {
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ return 0;
+ }
+ }
+ else {
+ if (!write_direct8(png_ptr, info_ptr, im)) {
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ return 0;
+ }
}
- myfree(data);
png_write_end(png_ptr, info_ptr);
return(1);
}
-static void
-get_png_tags(i_img *im, png_structp png_ptr, png_infop info_ptr, int bit_depth);
-
typedef struct {
char *warnings;
} i_png_read_state, *i_png_read_statep;
png_read_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL);
- mm_log((1,
- "png_get_IHDR results: width %d, height %d, bit_depth %d, color_type %d, interlace_type %d\n",
- width,height,bit_depth,color_type,interlace_type));
+ mm_log((1, "png_get_IHDR results: width %u, height %u, bit_depth %d, color_type %d, interlace_type %d\n",
+ (unsigned)width, (unsigned)height, bit_depth,color_type,interlace_type));
CC2C[PNG_COLOR_TYPE_GRAY]=1;
CC2C[PNG_COLOR_TYPE_PALETTE]=3;
}
if (im)
- get_png_tags(im, png_ptr, info_ptr, bit_depth);
+ get_png_tags(im, png_ptr, info_ptr, bit_depth, color_type);
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);
return im;
}
+struct png_text_name {
+ const char *keyword;
+ const char *tagname;
+};
+
+static const struct png_text_name
+text_tags[] = {
+ { "Author", "png_author" },
+ { "Comment", "i_comment" },
+ { "Copyright", "png_copyright" },
+ { "Creation Time", "png_creation_time" },
+ { "Description", "png_description" },
+ { "Disclaimer", "png_disclaimer" },
+ { "Software", "png_software" },
+ { "Source", "png_source" },
+ { "Title", "png_title" },
+ { "Warning", "png_warning" }
+};
+
+static const int text_tags_count = sizeof(text_tags) / sizeof(*text_tags);
+
+static const char * const
+chroma_tags[] = {
+ "png_chroma_white_x",
+ "png_chroma_white_y",
+ "png_chroma_red_x",
+ "png_chroma_red_y",
+ "png_chroma_green_x",
+ "png_chroma_green_y",
+ "png_chroma_blue_x",
+ "png_chroma_blue_y"
+};
+
+static const int chroma_tag_count = sizeof(chroma_tags) / sizeof(*chroma_tags);
+
static void
-get_png_tags(i_img *im, png_structp png_ptr, png_infop info_ptr, int bit_depth) {
+get_png_tags(i_img *im, png_structp png_ptr, png_infop info_ptr,
+ int bit_depth, int color_type) {
png_uint_32 xres, yres;
int unit_type;
i_tags_set(&im->tags, "i_format", "png", -1);
if (png_get_pHYs(png_ptr, info_ptr, &xres, &yres, &unit_type)) {
- mm_log((1,"pHYs (%d, %d) %d\n", xres, yres, unit_type));
+ mm_log((1,"pHYs (%u, %u) %d\n", (unsigned)xres, (unsigned)yres, unit_type));
if (unit_type == PNG_RESOLUTION_METER) {
i_tags_set_float2(&im->tags, "i_xres", 0, xres * 0.0254, 5);
i_tags_set_float2(&im->tags, "i_yres", 0, yres * 0.0254, 5);
/* the various readers can call png_set_expand(), libpng will make
it's internal record of bit_depth at least 8 in that case */
i_tags_setn(&im->tags, "png_bits", bit_depth);
+
+ if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sRGB)) {
+ int intent;
+ if (png_get_sRGB(png_ptr, info_ptr, &intent)) {
+ i_tags_setn(&im->tags, "png_srgb_intent", intent);
+ }
+ }
+ else {
+ /* Ignore these if there's an sRGB chunk, libpng simulates
+ their existence if there's an sRGB chunk, and the PNG spec says
+ that these are ignored if the sRGB is present, so ignore them.
+ */
+ double gamma;
+ double chroma[8];
+
+ if (png_get_gAMA(png_ptr, info_ptr, &gamma)) {
+ i_tags_set_float2(&im->tags, "png_gamma", 0, gamma, 4);
+ }
+
+ if (png_get_cHRM(png_ptr, info_ptr, chroma+0, chroma+1,
+ chroma+2, chroma+3, chroma+4, chroma+5,
+ chroma+6, chroma+7)) {
+ int i;
+
+ for (i = 0; i < chroma_tag_count; ++i)
+ i_tags_set_float2(&im->tags, chroma_tags[i], 0, chroma[i], 4);
+ }
+ }
+
+ {
+ int num_text;
+ png_text *text;
+
+ if (png_get_text(png_ptr, info_ptr, &text, &num_text)) {
+ int i;
+ int custom_index = 0;
+ for (i = 0; i < num_text; ++i) {
+ int j;
+ int found = 0;
+ int compressed = text[i].compression == PNG_ITXT_COMPRESSION_zTXt
+ || text[i].compression == PNG_TEXT_COMPRESSION_zTXt;
+
+ for (j = 0; j < text_tags_count; ++j) {
+ if (strcmp(text_tags[j].keyword, text[i].key) == 0) {
+ char tag_name[50];
+ i_tags_set(&im->tags, text_tags[j].tagname, text[i].text, -1);
+ if (compressed) {
+ sprintf(tag_name, "%s_compressed", text_tags[j].tagname);
+ i_tags_setn(&im->tags, tag_name, 1);
+ }
+ found = 1;
+ break;
+ }
+ }
+
+ if (!found) {
+ char tag_name[50];
+ sprintf(tag_name, "png_text%d_key", custom_index);
+ i_tags_set(&im->tags, tag_name, text[i].key, -1);
+ sprintf(tag_name, "png_text%d_text", custom_index);
+ i_tags_set(&im->tags, tag_name, text[i].text, -1);
+ sprintf(tag_name, "png_text%d_type", custom_index);
+ i_tags_set(&im->tags, tag_name,
+ (text[i].compression == PNG_TEXT_COMPRESSION_NONE
+ || text[i].compression == PNG_TEXT_COMPRESSION_zTXt) ?
+ "text" : "itxt", -1);
+ if (compressed) {
+ sprintf(tag_name, "png_text%d_compressed", custom_index);
+ i_tags_setn(&im->tags, tag_name, 1);
+ }
+ ++custom_index;
+ }
+ }
+ }
+ }
+
+ {
+ png_time *mod_time;
+
+ if (png_get_tIME(png_ptr, info_ptr, &mod_time)) {
+ char time_formatted[80];
+
+ sprintf(time_formatted, "%d-%02d-%02dT%02d:%02d:%02d",
+ mod_time->year, mod_time->month, mod_time->day,
+ mod_time->hour, mod_time->minute, mod_time->second);
+ i_tags_set(&im->tags, "png_time", time_formatted, -1);
+ }
+ }
+
+ {
+ png_color_16 *back;
+ i_color c;
+
+ if (png_get_bKGD(png_ptr, info_ptr, &back)) {
+ switch (color_type) {
+ case PNG_COLOR_TYPE_GRAY:
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ {
+ /* lib png stores the raw gray value rather than scaling it
+ to 16-bit (or 8), we use 8-bit color for i_background */
+
+ int gray;
+ switch (bit_depth) {
+ case 16:
+ gray = back->gray >> 8;
+ break;
+ case 8:
+ gray = back->gray;
+ break;
+ case 4:
+ gray = 0x11 * back->gray;
+ break;
+ case 2:
+ gray = 0x55 * back->gray;
+ break;
+ case 1:
+ gray = back->gray ? 0xFF : 0;
+ break;
+ default:
+ gray = 0;
+ }
+ c.rgb.r = c.rgb.g = c.rgb.b = gray;
+ break;
+ }
+
+ case PNG_COLOR_TYPE_RGB:
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ {
+ c.rgb.r = bit_depth == 16 ? (back->red >> 8) : back->red;
+ c.rgb.g = bit_depth == 16 ? (back->green >> 8) : back->green;
+ c.rgb.b = bit_depth == 16 ? (back->blue >> 8) : back->blue;
+ break;
+ }
+
+ case PNG_COLOR_TYPE_PALETTE:
+ c.rgb.r = back->red;
+ c.rgb.g = back->green;
+ c.rgb.b = back->blue;
+ break;
+ }
+
+ c.rgba.a = 255;
+ i_tags_set_color(&im->tags, "i_background", 0, &c);
+ }
+ }
+}
+
+#define GET_STR_BUF_SIZE 40
+
+static int
+set_png_tags(i_img *im, png_structp png_ptr, png_infop info_ptr) {
+ double xres, yres;
+ int aspect_only, have_res = 1;
+
+ if (i_tags_get_float(&im->tags, "i_xres", 0, &xres)) {
+ if (i_tags_get_float(&im->tags, "i_yres", 0, &yres))
+ ; /* nothing to do */
+ else
+ yres = xres;
+ }
+ else {
+ if (i_tags_get_float(&im->tags, "i_yres", 0, &yres))
+ xres = yres;
+ else
+ have_res = 0;
+ }
+ if (have_res) {
+ aspect_only = 0;
+ i_tags_get_int(&im->tags, "i_aspect_only", 0, &aspect_only);
+ xres /= 0.0254;
+ yres /= 0.0254;
+ png_set_pHYs(png_ptr, info_ptr, xres + 0.5, yres + 0.5,
+ aspect_only ? PNG_RESOLUTION_UNKNOWN : PNG_RESOLUTION_METER);
+ }
+
+ {
+ int intent;
+ if (i_tags_get_int(&im->tags, "png_srgb_intent", 0, &intent)) {
+ if (intent < 0 || intent >= PNG_sRGB_INTENT_LAST) {
+ i_push_error(0, "tag png_srgb_intent out of range");
+ return 0;
+ }
+ png_set_sRGB(png_ptr, info_ptr, intent);
+ }
+ else {
+ double chroma[8], gamma;
+ int i;
+ int found_chroma_count = 0;
+
+ for (i = 0; i < chroma_tag_count; ++i) {
+ if (i_tags_get_float(&im->tags, chroma_tags[i], 0, chroma+i))
+ ++found_chroma_count;
+ }
+
+ if (found_chroma_count) {
+ if (found_chroma_count != chroma_tag_count) {
+ i_push_error(0, "all png_chroma_* tags must be supplied or none");
+ return 0;
+ }
+
+ png_set_cHRM(png_ptr, info_ptr, chroma[0], chroma[1], chroma[2],
+ chroma[3], chroma[4], chroma[5], chroma[6], chroma[7]);
+ }
+
+ if (i_tags_get_float(&im->tags, "png_gamma", 0, &gamma)) {
+ png_set_gAMA(png_ptr, info_ptr, gamma);
+ }
+ }
+ }
+
+ {
+ /* png_set_text() is sparsely documented, it isn't indicated whether
+ multiple calls add to or replace the lists of texts, and
+ whether the text/keyword data is copied or not.
+
+ Examining the linpng code reveals that png_set_text() adds to
+ the list and that the text is copied.
+ */
+ int i;
+
+ /* do our standard tags */
+ for (i = 0; i < text_tags_count; ++i) {
+ char buf[GET_STR_BUF_SIZE];
+ size_t size;
+ const char *data;
+
+ data = get_string2(&im->tags, text_tags[i].tagname, buf, &size);
+ if (data) {
+ png_text text;
+ int compression = size > 1000;
+ char compress_tag[40];
+
+ if (memchr(data, '\0', size)) {
+ i_push_errorf(0, "tag %s may not contain NUL characters", text_tags[i].tagname);
+ return 0;
+ }
+
+ sprintf(compress_tag, "%s_compressed", text_tags[i].tagname);
+ i_tags_get_int(&im->tags, compress_tag, 0, &compression);
+
+ text.compression = compression ? PNG_TEXT_COMPRESSION_zTXt
+ : PNG_TEXT_COMPRESSION_NONE;
+ text.key = (char *)text_tags[i].keyword;
+ text.text_length = size;
+ text.text = (char *)data;
+#ifdef PNG_iTXt_SUPPORTED
+ text.itxt_length = 0;
+ text.lang = NULL;
+ text.lang_key = NULL;
+#endif
+
+ png_set_text(png_ptr, info_ptr, &text, 1);
+ }
+ }
+
+ /* for non-standard tags ensure keywords are limited to 1 to 79
+ characters */
+ i = 0;
+ while (1) {
+ char tag_name[50];
+ char key_buf[GET_STR_BUF_SIZE], value_buf[GET_STR_BUF_SIZE];
+ const char *key, *value;
+ size_t key_size, value_size;
+
+ sprintf(tag_name, "png_text%d_key", i);
+ key = get_string2(&im->tags, tag_name, key_buf, &key_size);
+
+ if (key) {
+ size_t k;
+ if (key_size < 1 || key_size > 79) {
+ i_push_errorf(0, "tag %s must be between 1 and 79 characters in length", tag_name);
+ return 0;
+ }
+
+ if (key[0] == ' ' || key[key_size-1] == ' ') {
+ i_push_errorf(0, "tag %s may not contain leading or trailing spaces", tag_name);
+ return 0;
+ }
+
+ if (strstr(key, " ")) {
+ i_push_errorf(0, "tag %s may not contain consecutive spaces", tag_name);
+ return 0;
+ }
+
+ for (k = 0; k < key_size; ++k) {
+ if (key[k] < 32 || (key[k] > 126 && key[k] < 161)) {
+ i_push_errorf(0, "tag %s may only contain Latin1 characters 32-126, 161-255", tag_name);
+ return 0;
+ }
+ }
+ }
+
+ sprintf(tag_name, "png_text%d_text", i);
+ value = get_string2(&im->tags, tag_name, value_buf, &value_size);
+
+ if (value) {
+ if (memchr(value, '\0', value_size)) {
+ i_push_errorf(0, "tag %s may not contain NUL characters", tag_name);
+ return 0;
+ }
+ }
+
+ if (key && value) {
+ png_text text;
+ int compression = value_size > 1000;
+
+ sprintf(tag_name, "png_text%d_compressed", i);
+ i_tags_get_int(&im->tags, tag_name, 0, &compression);
+
+ text.compression = compression ? PNG_TEXT_COMPRESSION_zTXt
+ : PNG_TEXT_COMPRESSION_NONE;
+ text.key = (char *)key;
+ text.text_length = value_size;
+ text.text = (char *)value;
+#ifdef PNG_iTXt_SUPPORTED
+ text.itxt_length = 0;
+ text.lang = NULL;
+ text.lang_key = NULL;
+#endif
+
+ png_set_text(png_ptr, info_ptr, &text, 1);
+ }
+ else if (key) {
+ i_push_errorf(0, "tag png_text%d_key found but not png_text%d_text", i, i);
+ return 0;
+ }
+ else if (value) {
+ i_push_errorf(0, "tag png_text%d_text found but not png_text%d_key", i, i);
+ return 0;
+ }
+ else {
+ break;
+ }
+ ++i;
+ }
+ }
+
+ {
+ char buf[GET_STR_BUF_SIZE];
+ size_t time_size;
+ const char *timestr = get_string2(&im->tags, "png_time", buf, &time_size);
+
+ if (timestr) {
+ int year, month, day, hour, minute, second;
+ png_time mod_time;
+
+ if (sscanf(timestr, "%d-%d-%dT%d:%d:%d", &year, &month, &day, &hour, &minute, &second) == 6) {
+ /* rough validation */
+ if (month < 1 || month > 12
+ || day < 1 || day > 31
+ || hour < 0 || hour > 23
+ || minute < 0 || minute > 59
+ || second < 0 || second > 60) {
+ i_push_error(0, "invalid date/time for png_time");
+ return 0;
+ }
+ mod_time.year = year;
+ mod_time.month = month;
+ mod_time.day = day;
+ mod_time.hour = hour;
+ mod_time.minute = minute;
+ mod_time.second = second;
+
+ png_set_tIME(png_ptr, info_ptr, &mod_time);
+ }
+ else {
+ i_push_error(0, "png_time must be formatted 'y-m-dTh:m:s'");
+ return 0;
+ }
+ }
+ }
+
+ {
+ /* no bKGD support yet, maybe later
+ it may be simpler to do it in the individual writers
+ */
+ }
+
+ return 1;
+}
+
+static const char *
+get_string2(i_img_tags *tags, const char *name, char *buf, size_t *size) {
+ int index;
+
+ if (i_tags_find(tags, name, 0, &index)) {
+ const i_img_tag *entry = tags->tags + index;
+
+ if (entry->data) {
+ *size = entry->size;
+
+ return entry->data;
+ }
+ else {
+ *size = sprintf(buf, "%d", entry->idata);
+
+ return buf;
+ }
+ }
+ return NULL;
+}
+
+static int
+write_direct8(png_structp png_ptr, png_infop info_ptr, i_img *im) {
+ unsigned char *data, *volatile vdata = NULL;
+ i_img_dim y;
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ if (vdata)
+ myfree(vdata);
+
+ return 0;
+ }
+
+ png_write_info(png_ptr, info_ptr);
+
+ vdata = data = mymalloc(im->xsize * im->channels);
+ for (y = 0; y < im->ysize; y++) {
+ i_gsamp(im, 0, im->xsize, y, data, NULL, im->channels);
+ png_write_row(png_ptr, (png_bytep)data);
+ }
+ myfree(data);
+
+ return 1;
+}
+
+static int
+write_direct16(png_structp png_ptr, png_infop info_ptr, i_img *im) {
+ unsigned *data, *volatile vdata = NULL;
+ unsigned char *tran_data, * volatile vtran_data = NULL;
+ i_img_dim samples_per_row = im->xsize * im->channels;
+
+ i_img_dim y;
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ if (vdata)
+ myfree(vdata);
+ if (vtran_data)
+ myfree(vtran_data);
+
+ return 0;
+ }
+
+ png_write_info(png_ptr, info_ptr);
+
+ vdata = data = mymalloc(samples_per_row * sizeof(unsigned));
+ vtran_data = tran_data = mymalloc(samples_per_row * 2);
+ for (y = 0; y < im->ysize; y++) {
+ i_img_dim i;
+ unsigned char *p = tran_data;
+ i_gsamp_bits(im, 0, im->xsize, y, data, NULL, im->channels, 16);
+ for (i = 0; i < samples_per_row; ++i) {
+ p[0] = data[i] >> 8;
+ p[1] = data[i] & 0xff;
+ p += 2;
+ }
+ png_write_row(png_ptr, (png_bytep)tran_data);
+ }
+ myfree(tran_data);
+ myfree(data);
+
+ return 1;
+}
+
+static int
+write_paletted(png_structp png_ptr, png_infop info_ptr, i_img *im, int bits) {
+ unsigned char *data, *volatile vdata = NULL;
+ i_img_dim y;
+ unsigned char pal_map[256];
+ png_color pcolors[256];
+ i_color colors[256];
+ int count = i_colorcount(im);
+ int i;
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ if (vdata)
+ myfree(vdata);
+
+ return 0;
+ }
+
+ i_getcolors(im, 0, colors, count);
+ if (im->channels < 3) {
+ /* convert the greyscale palette to color */
+ int i;
+ for (i = 0; i < count; ++i) {
+ i_color *c = colors + i;
+ c->channel[3] = c->channel[1];
+ c->channel[2] = c->channel[1] = c->channel[0];
+ }
+ }
+
+ if (i_img_has_alpha(im)) {
+ int i;
+ int bottom_index = 0, top_index = count-1;
+
+ /* fill out the palette map */
+ for (i = 0; i < count; ++i)
+ pal_map[i] = i;
+
+ /* the PNG spec suggests sorting the palette by alpha, but that's
+ unnecessary - all we want to do is move the opaque entries to
+ the end */
+ while (bottom_index < top_index) {
+ if (colors[bottom_index].rgba.a == 255) {
+ pal_map[bottom_index] = top_index;
+ pal_map[top_index--] = bottom_index;
+ }
+ ++bottom_index;
+ }
+ }
+
+ for (i = 0; i < count; ++i) {
+ int srci = i_img_has_alpha(im) ? pal_map[i] : i;
+
+ pcolors[i].red = colors[srci].rgb.r;
+ pcolors[i].green = colors[srci].rgb.g;
+ pcolors[i].blue = colors[srci].rgb.b;
+ }
+
+ png_set_PLTE(png_ptr, info_ptr, pcolors, count);
+
+ if (i_img_has_alpha(im)) {
+ unsigned char trans[256];
+ int i;
+
+ for (i = 0; i < count && colors[pal_map[i]].rgba.a != 255; ++i) {
+ trans[i] = colors[pal_map[i]].rgba.a;
+ }
+ png_set_tRNS(png_ptr, info_ptr, trans, i, NULL);
+ }
+
+ png_write_info(png_ptr, info_ptr);
+
+ png_set_packing(png_ptr);
+
+ vdata = data = mymalloc(im->xsize);
+ for (y = 0; y < im->ysize; y++) {
+ i_gpal(im, 0, im->xsize, y, data);
+ if (i_img_has_alpha(im)) {
+ i_img_dim x;
+ for (x = 0; x < im->xsize; ++x)
+ data[x] = pal_map[data[x]];
+ }
+ png_write_row(png_ptr, (png_bytep)data);
+ }
+ myfree(data);
+
+ return 1;
+}
+
+static int
+write_bilevel(png_structp png_ptr, png_infop info_ptr, i_img *im) {
+ unsigned char *data, *volatile vdata = NULL;
+ i_img_dim y;
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ if (vdata)
+ myfree(vdata);
+
+ return 0;
+ }
+
+ png_write_info(png_ptr, info_ptr);
+
+ png_set_packing(png_ptr);
+
+ vdata = data = mymalloc(im->xsize);
+ for (y = 0; y < im->ysize; y++) {
+ i_gsamp(im, 0, im->xsize, y, data, NULL, 1);
+ png_write_row(png_ptr, (png_bytep)data);
+ }
+ myfree(data);
+
+ return 1;
}
static void
projects / imager.git / blobdiff