...

diff --git a/coders/png.c b/coders/png.c
index 4f7e09896eb153fe359f4f88df81f39fe13b7b0c..7fc2699f482a41a24631fa438923aab6d95aaf17 100644 (file)
--- a/coders/png.c
+++ b/coders/png.c
@@ -11357,6 +11357,7 @@ static MagickBooleanType WriteOnePNGImage(MngInfo *mng_info,
   if (pixel_info == (MemoryInfo *) NULL)
     png_error(ping,"Allocation of memory for pixels failed");
   ping_pixels=(unsigned char *) GetVirtualMemoryBlob(pixel_info);
+  (void) memset(png_pixels,0,rowbytes*sizeof(*ping_pixels));
   /*
     Initialize image scanlines.
   */