--- /dev/null
+/* png.c
+
+ Copyright (c) 2003/2004/2005 Matthias Kramm <kramm@quiss.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <fcntl.h>
+#include <zlib.h>
+#include "png.h"
+
+typedef unsigned char U8;
+typedef unsigned long U32;
+typedef struct _COL {
+ U8 a,r,g,b;
+} COL;
+
+#define REVERSESWAP16(s) ((((s)>>8)&0x00ff)|(((s)<<8)&0xff00))
+#define REVERSESWAP32(s) (REVERSESWAP16(((s)>>16)&0x0000ffff)|((REVERSESWAP16(s)<<16)&0xffff0000))
+
+int png_read_chunk(char (*head)[4], int*destlen, U8**destdata, FILE*fi)
+{
+ unsigned int len;
+ if(destlen) *destlen=0;
+ if(destdata) *destdata=0;
+ if(!fread(&len, 4, 1, fi)) {
+ return 0;
+ }
+ if(!fread(head, 4, 1, fi)) {
+ return 0;
+ }
+ len = REVERSESWAP32(len);
+ if(destlen) *destlen = len;
+ if(destdata) {
+ if(!len) {
+ *destdata = 0;
+ } else {
+ *destdata = (U8*)malloc(len);
+ if(!fread(*destdata, len, 1, fi)) {
+ *destdata = 0;
+ if(destlen) *destlen=0;
+ return 0;
+ }
+ }
+ fseek(fi, 4, SEEK_CUR);
+
+ } else {
+ fseek(fi, len+4, SEEK_CUR);
+ }
+ return 1;
+}
+
+unsigned int png_get_dword(FILE*fi)
+{
+ unsigned int a;
+ fread(&a,4,1,fi);
+ return REVERSESWAP32(a);
+}
+
+struct png_header
+{
+ int width;
+ int height;
+ int bpp;
+ int mode;
+};
+
+int png_read_header(FILE*fi, struct png_header*header)
+{
+ char id[4];
+ int len;
+ int ok=0;
+ U8 head[8] = {137,80,78,71,13,10,26,10};
+ U8 head2[8];
+ U8*data;
+ fread(head2,8,1,fi);
+ if(strncmp((const char*)head,(const char*)head2,4))
+ return 0;
+
+ while(png_read_chunk(&id, &len, &data, fi))
+ {
+ //printf("Chunk: %c%c%c%c (len:%d)\n", id[0],id[1],id[2],id[3], len);
+ if(!strncasecmp(id, "IHDR", 4)) {
+ char a,b,c,f,i;
+ if(len < 8) exit(1);
+ header->width = REVERSESWAP32(*(U32*)&data[0]);
+ header->height = REVERSESWAP32(*(U32*)&data[4]);
+ a = data[8]; // should be 8
+ b = data[9]; // should be 3(indexed) or 2(rgb)
+
+ c = data[10]; // compression mode (0)
+ f = data[11]; // filter mode (0)
+ i = data[12]; // interlace mode (0)
+
+ if(b!=0 && b!=2 && b!=3 && b!=6) {
+ fprintf(stderr, "Image mode %d not supported!\n", b);
+ if(b == 4) {
+ fprintf(stderr, "(This is a grayscale image with alpha channel-\n");
+ fprintf(stderr, " try converting it into an RGB image with alpha channel)\n");
+ }
+ return 0;
+ }
+ if(a!=8 && (b==2 || b==6)) {
+ printf("Bpp %d in mode %d not supported!\n", a);
+ return 0;
+ }
+ if(c!=0) {
+ printf("Compression mode %d not supported!\n", c);
+ return 0;
+ }
+ if(f!=0) {
+ printf("Filter mode %d not supported!\n", f);
+ return 0;
+ }
+ if(i!=0) {
+ printf("Interlace mode %d not supported!\n", i);
+ return 0;
+ }
+ //printf("%dx%d bpp:%d mode:%d comp:%d filter:%d interlace:%d\n",header->width, header->height, a,b,c,f,i);
+ header->bpp = a;
+ header->mode = b;
+ ok = 1;
+ }
+
+ free(data);
+ }
+ return ok;
+}
+
+typedef unsigned char byte;
+#define ABS(a) ((a)>0?(a):(-(a)))
+byte inline PaethPredictor (byte a,byte b,byte c)
+{
+ // a = left, b = above, c = upper left
+ int p = a + b - c; // initial estimate
+ int pa = ABS(p - a); // distances to a, b, c
+ int pb = ABS(p - b);
+ int pc = ABS(p - c);
+ // return nearest of a,b,c,
+ // breaking ties in order a,b,c.
+ if (pa <= pb && pa <= pc)
+ return a;
+ else if (pb <= pc)
+ return b;
+ else return c;
+}
+
+void applyfilter1(int mode, U8*src, U8*old, U8*dest, int width)
+{
+ int x;
+ unsigned char last=0;
+ unsigned char upperlast=0;
+
+ if(mode==0) {
+ for(x=0;x<width;x++) {
+ *dest = *src;
+ dest++;
+ src++;
+ }
+ }
+ else if(mode==1) {
+ for(x=0;x<width;x++) {
+ *dest = *src+last;
+ last = *dest;
+ dest++;
+ src++;
+ }
+ }
+ else if(mode==2) {
+ for(x=0;x<width;x++) {
+ *dest = *src+*old;
+ dest++;
+ old++;
+ src++;
+ }
+ }
+ else if(mode==3) {
+ for(x=0;x<width;x++) {
+ *dest = *src+(*old+last)/2;
+ dest++;
+ old++;
+ src++;
+ }
+ }
+ else if(mode==4) {
+ for(x=0;x<width;x++) {
+ *dest = *src+PaethPredictor(last,*old,upperlast);
+ last = *dest;
+ upperlast = *old;
+ dest++;
+ old++;
+ src++;
+ }
+ }
+
+}
+
+void applyfilter2(int mode, U8*src, U8*old, U8*dest, int width)
+{
+ int x;
+ unsigned char lasta=0;
+ unsigned char lastb=0;
+ unsigned char upperlasta=0;
+ unsigned char upperlastb=0;
+
+ if(mode==0) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[0];
+ dest[1] = src[1];
+ dest+=2;
+ src+=2;
+ }
+ }
+ else if(mode==1) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[0]+lasta;
+ dest[1] = src[1]+lastb;
+ lasta = dest[0];
+ lastb = dest[1];
+ dest+=2;
+ src+=2;
+ }
+ }
+ else if(mode==2) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[0]+old[0];
+ dest[1] = src[1]+old[1];
+ dest+=2;
+ old+=2;
+ src+=2;
+ }
+ }
+ else if(mode==3) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[0]+(old[0]+lasta)/2;
+ dest[1] = src[1]+(old[1]+lastb)/2;
+ lasta = dest[0];
+ lastb = dest[1];
+ dest+=2;
+ old+=2;
+ src+=2;
+ }
+ }
+ else if(mode==4) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[0]+PaethPredictor(lasta,old[0],upperlasta);
+ dest[1] = src[1]+PaethPredictor(lastb,old[1],upperlastb);
+ lasta = dest[0];
+ lastb = dest[1];
+ upperlasta = old[0];
+ upperlastb = old[1];
+ dest+=2;
+ old+=2;
+ src+=2;
+ }
+ }
+}
+
+
+/* also performs 24 bit conversion! */
+void applyfilter3(int mode, U8*src, U8*old, U8*dest, int width)
+{
+ int x;
+ unsigned char lastr=0;
+ unsigned char lastg=0;
+ unsigned char lastb=0;
+ unsigned char upperlastr=0;
+ unsigned char upperlastg=0;
+ unsigned char upperlastb=0;
+
+ if(mode==0) {
+ for(x=0;x<width;x++) {
+ dest[0] = 255;
+ dest[1] = src[0];
+ dest[2] = src[1];
+ dest[3] = src[2];
+ dest+=4;
+ src+=3;
+ }
+ }
+ else if(mode==1) {
+ for(x=0;x<width;x++) {
+ dest[0] = 255;
+ dest[1] = src[0]+lastr;
+ dest[2] = src[1]+lastg;
+ dest[3] = src[2]+lastb;
+ lastr = dest[1];
+ lastg = dest[2];
+ lastb = dest[3];
+ dest+=4;
+ src+=3;
+ }
+ }
+ else if(mode==2) {
+ for(x=0;x<width;x++) {
+ dest[0] = 255;
+ dest[1] = src[0]+old[1];
+ dest[2] = src[1]+old[2];
+ dest[3] = src[2]+old[3];
+ dest+=4;
+ old+=4;
+ src+=3;
+ }
+ }
+ else if(mode==3) {
+ for(x=0;x<width;x++) {
+ dest[0] = 255;
+ dest[1] = src[0]+(old[1]+lastr)/2;
+ dest[2] = src[1]+(old[2]+lastg)/2;
+ dest[3] = src[2]+(old[3]+lastb)/2;
+ lastr = dest[1];
+ lastg = dest[2];
+ lastb = dest[3];
+ dest+=4;
+ old+=4;
+ src+=3;
+ }
+ }
+ else if(mode==4) {
+ for(x=0;x<width;x++) {
+ dest[0] = 255;
+ dest[1] = src[0]+PaethPredictor(lastr,old[1],upperlastr);
+ dest[2] = src[1]+PaethPredictor(lastg,old[2],upperlastg);
+ dest[3] = src[2]+PaethPredictor(lastb,old[3],upperlastb);
+ lastr = dest[1];
+ lastg = dest[2];
+ lastb = dest[3];
+ upperlastr = old[1];
+ upperlastg = old[2];
+ upperlastb = old[3];
+ dest+=4;
+ old+=4;
+ src+=3;
+ }
+ }
+}
+
+void inline applyfilter4(int mode, U8*src, U8*old, U8*dest, int width)
+{
+ int x;
+ unsigned char lastr=0;
+ unsigned char lastg=0;
+ unsigned char lastb=0;
+ unsigned char lasta=0;
+ unsigned char upperlastr=0;
+ unsigned char upperlastg=0;
+ unsigned char upperlastb=0;
+ unsigned char upperlasta=0;
+
+ if(mode==0) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[3];
+ dest[1] = src[0];
+ dest[2] = src[1];
+ dest[3] = src[2];
+ dest+=4;
+ src+=4;
+ }
+ }
+ else if(mode==1) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[3]+lasta;
+ dest[1] = src[0]+lastr;
+ dest[2] = src[1]+lastg;
+ dest[3] = src[2]+lastb;
+ lasta = dest[0];
+ lastr = dest[1];
+ lastg = dest[2];
+ lastb = dest[3];
+ dest+=4;
+ src+=4;
+ }
+ }
+ else if(mode==2) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[3]+old[0];
+ dest[1] = src[0]+old[1];
+ dest[2] = src[1]+old[2];
+ dest[3] = src[2]+old[3];
+ dest+=4;
+ old+=4;
+ src+=4;
+ }
+ }
+ else if(mode==3) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[3]+(old[0]+lasta)/2;
+ dest[1] = src[0]+(old[1]+lastr)/2;
+ dest[2] = src[1]+(old[2]+lastg)/2;
+ dest[3] = src[2]+(old[3]+lastb)/2;
+ lasta = dest[0];
+ lastr = dest[1];
+ lastg = dest[2];
+ lastb = dest[3];
+ dest+=4;
+ old+=4;
+ src+=4;
+ }
+ }
+ else if(mode==4) {
+ for(x=0;x<width;x++) {
+ dest[0] = src[3]+PaethPredictor(lasta,old[0],upperlasta);
+ dest[1] = src[0]+PaethPredictor(lastr,old[1],upperlastr);
+ dest[2] = src[1]+PaethPredictor(lastg,old[2],upperlastg);
+ dest[3] = src[2]+PaethPredictor(lastb,old[3],upperlastb);
+ lasta = dest[0];
+ lastr = dest[1];
+ lastg = dest[2];
+ lastb = dest[3];
+ upperlasta = old[0];
+ upperlastr = old[1];
+ upperlastg = old[2];
+ upperlastb = old[3];
+ dest+=4;
+ old+=4;
+ src+=4;
+ }
+ }
+}
+
+
+int getPNGdimensions(char*sname, int*destwidth, int*destheight)
+{
+ FILE*fi;
+ struct png_header header;
+ if ((fi = fopen(sname, "rb")) == NULL) {
+ fprintf(stderr, "Couldn't open %s\n", sname);
+ return 0;
+ }
+ if(!png_read_header(fi, &header)) {
+ fprintf(stderr, "Error reading header from file %s\n", sname);
+ return 0;
+ }
+
+ *destwidth = header.width;
+ *destheight = header.height;
+ return 1;
+}
+
+int getPNG(char*sname, int*destwidth, int*destheight, unsigned char**destdata)
+{
+ char tagid[4];
+ int len;
+ U8*data;
+ U8*imagedata;
+ U8*zimagedata=0;
+ unsigned long int imagedatalen;
+ unsigned long int zimagedatalen=0;
+ U8*palette = 0;
+ int palettelen = 0;
+ U8*alphapalette = 0;
+ int alphapalettelen = 0;
+ struct png_header header;
+ int bypp;
+
+ FILE *fi;
+ U8 *scanline;
+
+ if ((fi = fopen(sname, "rb")) == NULL) {
+ printf("Couldn't open %s\n", sname);
+ return 0;
+ }
+
+ if(!png_read_header(fi, &header)) {
+ printf("Error reading header from file %s\n", sname);
+ return 0;
+ }
+
+ if(header.mode == 3 || header.mode == 0) bypp = 1;
+ else
+ if(header.mode == 2) bypp = 3;
+ else
+ if(header.mode == 6) bypp = 4;
+ else {
+ printf("ERROR: mode:%d\n", header.mode);
+ return 0;
+ }
+
+ imagedatalen = bypp * header.width * header.height + 65536;
+ imagedata = (U8*)malloc(imagedatalen);
+
+ fseek(fi,8,SEEK_SET);
+ while(!feof(fi))
+ {
+ if(!png_read_chunk(&tagid, &len, &data, fi))
+ break;
+ if(!strncmp(tagid, "IEND", 4)) {
+ break;
+ }
+ if(!strncmp(tagid, "PLTE", 4)) {
+ palette = data;
+ palettelen = len/3;
+ data = 0; //don't free data
+ //printf("%d colors in palette\n", palettelen);
+ }
+ if(!strncmp(tagid, "tRNS", 4)) {
+ if(header.mode == 3) {
+ alphapalette = data;
+ alphapalettelen = len;
+ data = 0; //don't free data
+ //printf("found %d alpha colors\n", alphapalettelen);
+ }
+ }
+ if(!strncmp(tagid, "IDAT", 4)) {
+ if(!zimagedata) {
+ zimagedatalen = len;
+ zimagedata = (U8*)malloc(len);
+ memcpy(zimagedata,data,len);
+ } else {
+ zimagedata = (U8*)realloc(zimagedata, zimagedatalen+len);
+ memcpy(&zimagedata[zimagedatalen], data, len);
+ zimagedatalen += len;
+ }
+ }
+ if(!strncmp(tagid, "tEXt", 4)) {
+ /*int t;
+ printf("Image Text: ");
+ for(t=0;t<len;t++) {
+ if(data[t]>=32 && data[t]<128)
+ printf("%c", data[t]);
+ else
+ printf("?");
+ }
+ printf("\n");*/
+ }
+ if(data)
+ free(data);
+ }
+
+ if(!zimagedata || uncompress(imagedata, &imagedatalen, zimagedata, zimagedatalen) != Z_OK) {
+ printf("Couldn't uncompress %s!\n", sname);
+ if(zimagedata)
+ free(zimagedata);
+ return 0;
+ }
+ free(zimagedata);
+ fclose(fi);
+
+ *destwidth = header.width;
+ *destheight = header.height;
+
+ if(header.mode == 6 || header.mode == 2)
+ {
+ U8*data2 = (U8*)malloc(header.width*header.height*4);
+ int i,s=0;
+ int x,y;
+ int pos=0;
+ *destdata = data2;
+ for(y=0;y<header.height;y++) {
+ int mode = imagedata[pos++]; //filter mode
+ U8*src;
+ U8*dest;
+ U8*old;
+ dest = &data2[(y*header.width)*4];
+
+ if(header.bpp == 8)
+ {
+ /* one byte per pixel */
+ src = &imagedata[pos];
+ pos+=header.width*(header.mode==6?4:3);
+ } else {
+ /* not implemented yet */
+ printf("ERROR: bpp:%d\n", header.bpp);
+ free(data2);
+ return 0;
+ }
+
+ if(!y) {
+ memset(data2,0,header.width*4);
+ old = &data2[y*header.width*4];
+ } else {
+ old = &data2[(y-1)*header.width*4];
+ }
+ if(header.mode == 6)
+ applyfilter4(mode, src, old, dest, header.width);
+ else // header.mode = 2
+ applyfilter3(mode, src, old, dest, header.width);
+ }
+ } else if(header.mode == 0 || header.mode == 3) {
+ COL*rgba = 0;
+ U8*data2 = (U8*)malloc(header.width*header.height*4);
+ U8*tmpline = (U8*)malloc(header.width+1);
+ U8*destline = (U8*)malloc(header.width+1);
+ int i,x,y;
+ int pos=0;
+
+ *destdata = data2;
+
+ if(header.mode == 0) { // grayscale palette
+ int mult = (0x1ff>>header.bpp);
+ palettelen = 1<<header.bpp;
+ rgba = (COL*)malloc(palettelen*sizeof(COL));
+ for(i=0;i<palettelen;i++) {
+ rgba[i].a = 255;
+ rgba[i].r = i*mult;
+ rgba[i].g = i*mult;
+ rgba[i].b = i*mult;
+ }
+ } else {
+ if(!palette) {
+ fprintf(stderr, "Error: No palette found!\n");
+ exit(1);
+ }
+ rgba = (COL*)malloc(palettelen*4);
+ /* 24->32 bit conversion */
+ for(i=0;i<palettelen;i++) {
+ rgba[i].r = palette[i*3+0];
+ rgba[i].g = palette[i*3+1];
+ rgba[i].b = palette[i*3+2];
+ if(alphapalette && i<alphapalettelen) {
+ rgba[i].a = alphapalette[i];
+ /*rgba[i].r = ((int)rgba[i].r*rgba[i].a)/255;
+ rgba[i].g = ((int)rgba[i].g*rgba[i].a)/255;
+ rgba[i].b = ((int)rgba[i].b*rgba[i].a)/255;*/
+ } else {
+ rgba[i].a = 255;
+ }
+ }
+ }
+
+ for(y=0;y<header.height;y++) {
+ int mode = imagedata[pos++]; //filter mode
+ int x;
+ U8*old;
+ U8*src;
+ src = &imagedata[pos];
+ if(header.bpp == 8) {
+ pos+=header.width;
+ } else {
+ int x,s=0;
+ int bitpos = 0;
+ U32 v = (1<<header.bpp)-1;
+ for(x=0;x<header.width;x++) {
+ U32 r = src[s/8]<<8 |
+ src[s/8+1];
+ int t;
+ tmpline[x] = (r>>(16-header.bpp-(s&7)))&v;
+ s+=header.bpp;
+ }
+ src = tmpline;
+ pos+=(header.width*header.bpp+7)/8;
+ }
+
+ if(!y) {
+ memset(destline,0,header.width);
+ old = &destline[y*header.width];
+ } else {
+ old = tmpline;
+ }
+ applyfilter1(mode, src, old, destline, header.width);
+ memcpy(tmpline,destline,header.width);
+ for(x=0;x<header.width;x++) {
+ *(COL*)&data2[y*header.width*4+x*4+0] = rgba[destline[x]];
+ }
+ }
+ free(tmpline);
+ free(destline);
+ free(rgba);
+ } else {
+ printf("expected PNG mode to be 2, 3 or 6 (is:%d)\n", header.mode);
+ return 0;
+ }
+
+ return 1;
+}
+
+static U32 mycrc32;
+
+static U32*crc32_table = 0;
+static void make_crc32_table(void)
+{
+ int t;
+ if(crc32_table)
+ return;
+ crc32_table = (U32*)malloc(1024);
+
+ for (t = 0; t < 256; t++) {
+ U32 c = t;
+ int s;
+ for (s = 0; s < 8; s++) {
+ c = (0xedb88320L*(c&1)) ^ (c >> 1);
+ }
+ crc32_table[t] = c;
+ }
+}
+static inline void png_write_byte(FILE*fi, U8 byte)
+{
+ fwrite(&byte,1,1,fi);
+ mycrc32 = crc32_table[(mycrc32 ^ byte) & 0xff] ^ (mycrc32 >> 8);
+}
+static void png_start_chunk(FILE*fi, char*type, int len)
+{
+ U8 mytype[4]={0,0,0,0};
+ U32 mylen = REVERSESWAP32(len);
+ memcpy(mytype,type,strlen(type));
+ fwrite(&mylen, 4, 1, fi);
+ mycrc32=0xffffffff;
+ png_write_byte(fi,mytype[0]);
+ png_write_byte(fi,mytype[1]);
+ png_write_byte(fi,mytype[2]);
+ png_write_byte(fi,mytype[3]);
+}
+static void png_write_bytes(FILE*fi, U8*bytes, int len)
+{
+ int t;
+ for(t=0;t<len;t++)
+ png_write_byte(fi,bytes[t]);
+}
+static void png_write_dword(FILE*fi, U32 dword)
+{
+ png_write_byte(fi,dword>>24);
+ png_write_byte(fi,dword>>16);
+ png_write_byte(fi,dword>>8);
+ png_write_byte(fi,dword);
+}
+static void png_end_chunk(FILE*fi)
+{
+ U32 tmp = REVERSESWAP32((mycrc32^0xffffffff));
+ fwrite(&tmp,4,1,fi);
+}
+
+void writePNG(char*filename, unsigned char*data, int width, int height)
+{
+ FILE*fi;
+ int crc;
+ int t;
+ U8 format;
+ U8 tmp;
+ U8* data2=0;
+ U8* data3=0;
+ U32 datalen;
+ U32 datalen2;
+ U32 datalen3;
+ U8 head[] = {137,80,78,71,13,10,26,10}; // PNG header
+ int cols;
+ char alpha = 1;
+ int pos = 0;
+ int error;
+ U32 tmp32;
+ int bpp;
+ int ret;
+
+ make_crc32_table();
+
+ bpp = 32;
+ cols = 0;
+ format = 5;
+
+ datalen = (width*height*bpp/8+cols*8);
+
+ fi = fopen(filename, "wb");
+ if(!fi) {
+ perror("open");
+ return;
+ }
+ fwrite(head,sizeof(head),1,fi);
+
+ png_start_chunk(fi, "IHDR", 13);
+ png_write_dword(fi,width);
+ png_write_dword(fi,height);
+ png_write_byte(fi,8);
+ if(format == 3)
+ png_write_byte(fi,3); //indexed
+ else if(format == 5 && alpha==0)
+ png_write_byte(fi,2); //rgb
+ else if(format == 5 && alpha==1)
+ png_write_byte(fi,6); //rgba
+ else return;
+
+ png_write_byte(fi,0); //compression mode
+ png_write_byte(fi,0); //filter mode
+ png_write_byte(fi,0); //interlace mode
+ png_end_chunk(fi);
+
+/* if(format == 3) {
+ png_start_chunk(fi, "PLTE", 768);
+
+ for(t=0;t<256;t++) {
+ png_write_byte(fi,palette[t].r);
+ png_write_byte(fi,palette[t].g);
+ png_write_byte(fi,palette[t].b);
+ }
+ png_end_chunk(fi);
+ }*/
+ {
+ int pos2 = 0;
+ int x,y;
+ int srcwidth = width * (bpp/8);
+ datalen3 = (width*4+5)*height;
+ data3 = (U8*)malloc(datalen3);
+ for(y=0;y<height;y++)
+ {
+ data3[pos2++]=0; //filter type
+ for(x=0;x<width;x++) {
+ data3[pos2++]=data[pos+1];
+ data3[pos2++]=data[pos+2];
+ data3[pos2++]=data[pos+3];
+ data3[pos2++]=data[pos+0]; //alpha
+ pos+=4;
+ }
+ pos+=((srcwidth+3)&~3)-srcwidth; //align
+ }
+ datalen3=pos2;
+ }
+
+ datalen2 = datalen3;
+ data2 = malloc(datalen2);
+
+ if((ret = compress (data2, &datalen2, data3, datalen3)) != Z_OK) {
+ fprintf(stderr, "zlib error in pic %d\n", ret);
+ return;
+ }
+ png_start_chunk(fi, "IDAT", datalen2);
+ png_write_bytes(fi,data2,datalen2);
+ png_end_chunk(fi);
+ png_start_chunk(fi, "IEND", 0);
+ png_end_chunk(fi);
+
+ free(data);
+ free(data2);
+ free(data3);
+}
git.asbjorn.biz / swftools.git / commitdiff