Index: libhb/muxmp4.c
===================================================================
--- libhb/muxmp4.c      (revision 1022)
+++ libhb/muxmp4.c      (working copy)
@@ -252,20 +252,31 @@
                        memcpy(nval, val, size);
 
                        float width, height;
-                       float widthRatio;
                        width = job->pixel_aspect_width;
                        height = job->pixel_aspect_height;
-                       widthRatio = (width / height) * 0x10000;
 
-                       uint32_t widthRatioInt;
-                       widthRatioInt = (uint32_t)widthRatio;
+                       uint32_t pixelRatioInt;
 
+                       if (width >= height)
+                       {
+                               pixelRatioInt = (uint32_t)((width / height) * 0x10000);
 #ifdef WORDS_BIGENDIAN
-                       ptr32[0] = widthRatioInt;
+                               ptr32[0] = pixelRatioInt;
 #else
-                       /* we need to switch the endianness, as the file format expects big endian */
-                       ptr32[0] = ((widthRatioInt & 0x000000FF) << 24) + ((widthRatioInt & 0x0000FF00) << 8) + ((widthRatioInt & 0x00FF0000) >> 8) + ((widthRatioInt & 0xFF000000) >> 24);
+                               /* 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[1] = pixelRatioInt;
+#else
+                               /* we need to switch the endianness, as the file format expects big endian */
+                               ptr32[1] = ((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");