Index: libhb/muxmp4.c
===================================================================
--- libhb/muxmp4.c	(revision 1237)
+++ libhb/muxmp4.c	(working copy)
@@ -234,54 +234,12 @@
 
 	/* apply the anamorphic transformation matrix if needed */
 
-	if( job->pixel_ratio ) {
-
-		uint8_t* val;
-		uint8_t nval[38];
-		uint32_t *ptr32 = (uint32_t*) (nval + 2);
-		uint32_t size;
-
-		MP4GetBytesProperty(m->file, "moov.trak.tkhd.reserved3", &val, &size);
-
-		if (size == 38) {
-
-			memcpy(nval, val, size);
-
+	if( job->pixel_ratio )
+    {
 			float width, height;
 			width = job->pixel_aspect_width;
 			height = job->pixel_aspect_height;
-
-           uint32_t pixelRatioInt;
-           if (width >= height)
-           {
-               pixelRatioInt = (uint32_t)((width / height) * 0x10000);
-
-#ifdef WORDS_BIGENDIAN
-               ptr32[0] = pixelRatioInt;
-#else
-               /* we need to switch the endianness, as the file format expects big endian */
-               ptr32[0] = ((pixelRatioInt & 0x000000FF) << 24) + ((pixelRatioInt & 0x0000FF00) << 8) + ((pixelRatioInt & 0x00FF0000) >> 8) + ((pixelRatioInt & 0xFF000000) >> 24);
-#endif
-
-           }
-           else
-           {
-               pixelRatioInt = (uint32_t)((height / width) * 0x10000);
-#ifdef WORDS_BIGENDIAN
-               ptr32[4] = pixelRatioInt;
-#else
-                /* we need to switch the endianness, as the file format expects big endian */
-                ptr32[4] = ((pixelRatioInt & 0x000000FF) << 24) + ((pixelRatioInt & 0x0000FF00) << 8) + ((pixelRatioInt & 0x00FF0000) >> 8) + ((pixelRatioInt & 0xFF000000) >> 24);
-#endif
-            }
-
-
-			if(!MP4SetBytesProperty(m->file, "moov.trak.tkhd.reserved3", nval, size)) {
-				hb_log("Problem setting transform matrix");
-			}
-			
-		}
-
+            MP4AddPixelAspectRatio(m->file, mux_data->track, (uint32_t)width, (uint32_t)height);
 	}
 
 	/* end of transformation matrix */