X-Git-Url: http://git.asbjorn.biz/?p=swftools.git;a=blobdiff_plain;f=lib%2Fpng.c;h=4aa4ddb41435cb0e9b9a6d1e7048a20426e0581f;hp=7190553ce51bbfe2f3ffc2b12361a7073f7347df;hb=5a4a20931aade60f0e99df0819fbd1c007a705da;hpb=27fe979dab6d4d058d5e608b8057f698804c93bf

diff --git a/lib/png.c b/lib/png.c
index 7190553..4aa4ddb 100644
--- a/lib/png.c
+++ b/lib/png.c
@@ -85,8 +85,8 @@ static unsigned int png_get_dword(FILE*fi)
 
 struct png_header
 {
-    int width;
-    int height;
+    unsigned width;
+    unsigned height;
     int bpp;
     int mode;
 };
@@ -167,7 +167,7 @@ static inline byte PaethPredictor (byte a,byte b,byte c)
         else return c;
 }
 
-static void applyfilter1(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, int width)
+static void applyfilter1(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, unsigned width)
 {
     int x;
     unsigned char last=0;
@@ -218,7 +218,7 @@ static void applyfilter1(int mode, unsigned char*src, unsigned char*old, unsigne
 
 }
 
-static void applyfilter2(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, int width)
+static void applyfilter2(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, unsigned width)
 {
     int x;
     unsigned char lasta=0;
@@ -281,7 +281,7 @@ static void applyfilter2(int mode, unsigned char*src, unsigned char*old, unsigne
 
 
 /* also performs 24 bit conversion! */
-static void applyfilter3(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, int width)
+static void applyfilter3(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, unsigned width)
 {
     int x;
     unsigned char lastr=0;
@@ -358,7 +358,7 @@ static void applyfilter3(int mode, unsigned char*src, unsigned char*old, unsigne
     }    
 }
 
-static void inline applyfilter4(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, int width)
+void png_inverse_filter_32(int mode, unsigned char*src, unsigned char*old, unsigned char*dest, unsigned width)
 {
     int x;
     unsigned char lastr=0;
@@ -441,8 +441,7 @@ static void inline applyfilter4(int mode, unsigned char*src, unsigned char*old,
     }    
 }
 
-
-EXPORT int getPNGdimensions(const char*sname, int*destwidth, int*destheight)
+EXPORT int getPNGdimensions(const char*sname, unsigned*destwidth, unsigned*destheight)
 {
     FILE*fi;
     struct png_header header;
@@ -456,17 +455,17 @@ EXPORT int getPNGdimensions(const char*sname, int*destwidth, int*destheight)
 
     *destwidth = header.width;
     *destheight = header.height;
+    fclose(fi);
     return 1;
 }
 
-EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char**destdata)
+EXPORT int getPNG(const char*sname, unsigned*destwidth, unsigned*destheight, unsigned char**destdata)
 {
     char tagid[4];
     int len;
     unsigned char*data;
     unsigned char*imagedata;
     unsigned char*zimagedata=0;
-    unsigned long int imagedatalen;
     unsigned long int zimagedatalen=0;
     unsigned char*palette = 0;
     int palettelen = 0;
@@ -500,7 +499,10 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
 	return 0;
     }
 
-    imagedatalen = bypp * header.width * header.height + 65536;
+    unsigned long long imagedatalen_64 = ((unsigned long long)header.width + 1) * header.height * bypp;
+    if(imagedatalen_64 > 0xffffffff)
+	return 0;
+    unsigned long imagedatalen = (unsigned long)imagedatalen_64;
     imagedata = (unsigned char*)malloc(imagedatalen);
 
     fseek(fi,8,SEEK_SET);
@@ -562,6 +564,7 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
         }
     }
     
+    fclose(fi);
     if(!zimagedata || uncompress(imagedata, &imagedatalen, zimagedata, zimagedatalen) != Z_OK) {
 	printf("Couldn't uncompress %s!\n", sname);
 	if(zimagedata)
@@ -569,7 +572,6 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
 	return 0;
     }
     free(zimagedata);
-    fclose(fi);
 
     *destwidth = header.width;
     *destheight = header.height;
@@ -649,7 +651,7 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
 		old = &data2[(y-1)*header.width*4];
 	    }
 	    if(header.mode == 6) { 
-		applyfilter4(mode, src, old, dest, header.width);
+		png_inverse_filter_32(mode, src, old, dest, header.width);
 	    } else { // header.mode = 2
 		applyfilter3(mode, src, old, dest, header.width);
 		/* replace alpha color */
@@ -1151,7 +1153,7 @@ static inline u32 color_hash(COL*col)
     return hash;
 }
 
-static int png_get_number_of_palette_entries(COL*img, int width, int height, COL*palette, char*has_alpha)
+static int png_get_number_of_palette_entries(COL*img, unsigned width, unsigned height, COL*palette, char*has_alpha)
 {
     int len = width*height;
     int t;
@@ -1266,11 +1268,11 @@ static void png_map_to_palette(COL*src, unsigned char*dest, int size, COL*palett
     }
 }
 
-static int png_apply_specific_filter_8(int filtermode, unsigned char*dest, unsigned char*src, int width)
+static int png_apply_specific_filter_8(int filtermode, unsigned char*dest, unsigned char*src, unsigned width)
 {
     int pos2 = 0;
     int pos = 0;
-    int srcwidth = width;
+    unsigned srcwidth = width;
     int x;
     if(filtermode == 0) {
 	for(x=0;x<width;x++) {
@@ -1309,11 +1311,11 @@ static int png_apply_specific_filter_8(int filtermode, unsigned char*dest, unsig
     return filtermode;
 }
 
-static int png_apply_specific_filter_32(int filtermode, unsigned char*dest, unsigned char*src, int width)
+static int png_apply_specific_filter_32(int filtermode, unsigned char*dest, unsigned char*src, unsigned width)
 {
     int pos2 = 0;
     int pos = 0;
-    int srcwidth = width*4;
+    unsigned srcwidth = width*4;
     int x;
     if(filtermode == 0) {
 	for(x=0;x<width;x++) {
@@ -1377,7 +1379,7 @@ static int png_apply_specific_filter_32(int filtermode, unsigned char*dest, unsi
     }
     return filtermode;
 }
-    
+
 static int*num_bits_table = 0;
 
 static void make_num_bits_table()
@@ -1396,14 +1398,82 @@ static void make_num_bits_table()
     }
 }
 
-static int png_apply_filter(unsigned char*dest, unsigned char*src, int width, int y, int bpp)
+static int png_find_best_filter(unsigned char*src, unsigned width, int bpp, int y)
 {
     make_num_bits_table();
-
+    
     int num_filters = y>0?5:2; //don't apply y-direction filter in first line
+
+    int bytes_per_pixel = bpp>>3;
+    int w = width*bytes_per_pixel;
+    int back_x = bytes_per_pixel;
+    int back_y = y?width*bytes_per_pixel:0;
+
+    unsigned char*pairs[5];
+    pairs[0] = calloc(1, 8192);
+    pairs[1] = calloc(1, 8192);
+    pairs[2] = calloc(1, 8192);
+    pairs[3] = calloc(1, 8192);
+    pairs[4] = calloc(1, 8192);
+    
+    unsigned char old[5];
+    int l = bytes_per_pixel - 1;
+    old[0] = src[l];
+    old[1] = src[l];
+    old[2] = src[l] - src[l-back_y];
+    old[3] = src[l] - src[l-back_y];
+    old[4] = src[l] - PaethPredictor(0, src[l-back_y], 0);
+
+    int different_pairs[5] = {0,0,0,0,0};
+
+    int x;
+    for(x=bytes_per_pixel;x<w;x++) {
+	unsigned char dest[5];
+	dest[0] = src[x];
+	dest[1] = src[x] - src[x-back_x];
+	dest[2] = src[x] - src[x-back_y];
+	dest[3] = src[x] - (src[x-back_x] + src[x-back_y])/2;
+	dest[4] = src[x] - PaethPredictor(src[x-back_x], src[x-back_y], src[x-back_x-back_y]);
+
+	int i;
+	for(i=0;i<5;i++) {
+	    int v = dest[i]<<8|old[i];
+	    int p = v>>3;
+	    int b = 1<<(v&7);
+	    if(!pairs[i][p]&b) {
+		pairs[i][p]|=b;
+		different_pairs[i]++;
+	    }
+	}
+	memcpy(old, dest, sizeof(old));
+    }
     int f;
     int best_nr = 0;
     int best_energy = INT_MAX;
+    for(f=0;f<num_filters;f++) {
+	int energy = different_pairs[f];
+	if(energy<best_energy) {
+	    best_nr = f;
+	    best_energy = energy;
+	}
+    }
+    free(pairs[0]);
+    free(pairs[1]);
+    free(pairs[2]);
+    free(pairs[3]);
+    free(pairs[4]);
+    return best_nr;
+}
+    
+    
+static int png_apply_filter(unsigned char*dest, unsigned char*src, unsigned width, int y, int bpp)
+{
+    int best_nr = 0;
+#if 0
+    make_num_bits_table();
+    int num_filters = y>0?5:2; //don't apply y-direction filter in first line
+    int f;
+    int best_energy = INT_MAX;
     int w = width*(bpp/8);
     unsigned char* pairs = malloc(8192);
     assert(bpp==8 || bpp==32);
@@ -1433,24 +1503,27 @@ static int png_apply_filter(unsigned char*dest, unsigned char*src, int width, in
 	    best_energy = energy;
 	}
     }
+    free(pairs);
+#else
+    best_nr = png_find_best_filter(src, width, bpp, y);
+#endif
     if(bpp==8)
 	png_apply_specific_filter_8(best_nr, dest, src, width);
     else
 	png_apply_specific_filter_32(best_nr, dest, src, width);
-    free(pairs);
     return best_nr;
 }
 
-int png_apply_filter_8(unsigned char*dest, unsigned char*src, int width, int y)
+int png_apply_filter_8(unsigned char*dest, unsigned char*src, unsigned width, int y)
 {
-    png_apply_filter(dest, src, width, y, 8);
+    return png_apply_filter(dest, src, width, y, 8);
 }
-int png_apply_filter_32(unsigned char*dest, unsigned char*src, int width, int y)
+int png_apply_filter_32(unsigned char*dest, unsigned char*src, unsigned width, int y)
 {
-    png_apply_filter(dest, src, width, y, 32);
+    return png_apply_filter(dest, src, width, y, 32);
 }
 
-EXPORT void savePNG(const char*filename, unsigned char*data, int width, int height, int numcolors)
+EXPORT void savePNG(const char*filename, unsigned char*data, unsigned width, unsigned height, int numcolors)
 {
     FILE*fi;
     int crc;
@@ -1458,8 +1531,6 @@ EXPORT void savePNG(const char*filename, unsigned char*data, int width, int heig
     unsigned char format;
     unsigned char tmp;
     unsigned char* data2=0;
-    u32 datalen;
-    u32 datalen2;
     unsigned char head[] = {137,80,78,71,13,10,26,10}; // PNG header
     int cols;
     char alpha = 1;
@@ -1496,8 +1567,6 @@ EXPORT void savePNG(const char*filename, unsigned char*data, int width, int heig
         png_quantize_image(data, width*height, numcolors, &data, palette);
     }
 
-    datalen = (width*height*bpp/8+cols*8);
-    
     fi = fopen(filename, "wb");
     if(!fi) {
 	perror("open");
@@ -1559,8 +1628,8 @@ EXPORT void savePNG(const char*filename, unsigned char*data, int width, int heig
     {
 	int x,y;
         int bypp = bpp/8;
-	int srcwidth = width * bypp;
-	int linelen = 1 + srcwidth;
+	unsigned srcwidth = width * bypp;
+	unsigned linelen = 1 + srcwidth;
         if(bypp==2) 
             linelen = 1 + ((srcwidth+1)&~1);
         else if(bypp==3) 
@@ -1620,11 +1689,11 @@ EXPORT void savePNG(const char*filename, unsigned char*data, int width, int heig
     fclose(fi);
 }
 
-EXPORT void writePNG(const char*filename, unsigned char*data, int width, int height)
+EXPORT void writePNG(const char*filename, unsigned char*data, unsigned width, unsigned height)
 {
     savePNG(filename, data, width, height, 0);
 }
-EXPORT void writePalettePNG(const char*filename, unsigned char*data, int width, int height)
+EXPORT void writePalettePNG(const char*filename, unsigned char*data, unsigned width, unsigned height)
 {
     savePNG(filename, data, width, height, 256);
 }