X-Git-Url: http://git.asbjorn.biz/?a=blobdiff_plain;f=lib%2Fpng.c;h=8578d2dbee85551bca002de752f55abe85312b2f;hb=57daf2c90dc409a2aa7030ce6ce996707e99967b;hp=fac4f77347625b116b8fa6d282c694c74192cc1f;hpb=6c3ab5574d31504d24710c2756899d49275c1a37;p=swftools.git

diff --git a/lib/png.c b/lib/png.c
index fac4f77..8578d2d 100644
--- a/lib/png.c
+++ b/lib/png.c
@@ -99,7 +99,7 @@ static int png_read_header(FILE*fi, struct png_header*header)
     unsigned char*data;
     fread(head2,8,1,fi);
     if(strncmp((const char*)head,(const char*)head2,4))
-	return 0;
+	return 0; // not a png file
     
     while(png_read_chunk(&id, &len, &data, fi))
     {
@@ -197,6 +197,7 @@ static void applyfilter1(int mode, unsigned char*src, unsigned char*old, unsigne
     else if(mode==3) {
 	for(x=0;x<width;x++) {
 	    *dest = *src+(*old+last)/2;
+	    last = *dest;
 	    dest++;
 	    old++;
 	    src++;
@@ -448,7 +449,6 @@ EXPORT int getPNGdimensions(const char*sname, int*destwidth, int*destheight)
 	return 0;
     }
     if(!png_read_header(fi, &header)) {
-	fprintf(stderr, "Error reading header from file %s\n", sname);
 	return 0;
     }
 
@@ -485,7 +485,6 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
     }
 
     if(!png_read_header(fi, &header)) {
-	printf("Error reading header from file %s\n", sname);
 	return 0;
     }
 
@@ -619,6 +618,9 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
 	int x,y;
 	int pos=0;
 	*destdata = data2;
+	
+	unsigned char* firstline = malloc(header.width*4);
+	memset(firstline,0,header.width*4);
 	for(y=0;y<header.height;y++) {
 	    int mode = imagedata[pos++]; //filter mode
 	    unsigned char*src;
@@ -639,8 +641,7 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
 	    }
 
 	    if(!y) {
-		memset(data2,0,header.width*4);
-		old = &data2[y*header.width*4];
+		old = firstline;
 	    } else {
 		old = &data2[(y-1)*header.width*4];
 	    }
@@ -661,6 +662,7 @@ EXPORT int getPNG(const char*sname, int*destwidth, int*destheight, unsigned char
 		}
 	    }
 	}
+	free(firstline);
         free(imagedata);
     } else if(header.mode == 0 || header.mode == 3) {
 	COL*rgba = 0;