libpng: fix bug on count of files generated

libpng/png.c

@@ -29,7 +29,7 @@ int main(int argc, char** argv){
 
 	srand48(1000);
 	
-	for (count=0; count<(1000);count++){
+	for (count=0; count<(c);count++){
 
 		for (i=0;i<width;i++){
 			rows[i].p = malloc (height * sizeof(pix));