diff --git a/tests/ffmpeg.regression.ref b/tests/ffmpeg.regression.ref
index 834fc8a738..21dd3f7892 100644
--- a/tests/ffmpeg.regression.ref
+++ b/tests/ffmpeg.regression.ref
@@ -23,9 +23,9 @@ stddev:  8.18 bytes:7602176
 496df9fe47c457144aac4178c960ad66 *./data/a-h263p.avi
 79649b61321beaaaa6413af8c18e4696 *./data/out.yuv
 stddev:  2.05 bytes:7602176
-74ab22f444b7f68f81624cabd69847be *./data/a-odivx.avi
-e48114a50ef4cfb4fe2016fa5b34ae4c *./data/out.yuv
-stddev:  8.02 bytes:7602176
+a8cc41cd5016bbb821e7c2691f5090ea *./data/a-odivx.mp4
+f890bc8bd9297f6eebeba98e58692ea7 *./data/out.yuv
+stddev:  8.02 bytes:7450624
 5704a082cc5c5970620123ae20566286 *./data/a-huffyuv.avi
 799d3db687f6cdd7a837ec156efc171f *./data/out.yuv
 stddev:  0.00 bytes:7602176
diff --git a/tests/regression.sh b/tests/regression.sh
index 06b25969a4..f4f20bf8d4 100755
--- a/tests/regression.sh
+++ b/tests/regression.sh
@@ -199,7 +199,7 @@ fi
 ###################################
 if [ -n "$do_mpeg4" ] ; then
 # mpeg4
-file=${outfile}odivx.avi
+file=${outfile}odivx.mp4
 do_ffmpeg $file -y -4mv -qscale 10 -f pgmyuv -i $raw_src -an -vcodec mpeg4 $file
 
 # mpeg4 decoding
diff --git a/tests/rotozoom.regression.ref b/tests/rotozoom.regression.ref
index bffc429fbe..629bf32845 100644
--- a/tests/rotozoom.regression.ref
+++ b/tests/rotozoom.regression.ref
@@ -23,9 +23,9 @@ stddev:  5.41 bytes:7602176
 c7683a914f7377dd0d3c2d0be6892fe9 *./data/a-h263p.avi
 a63dcff871fd46481a4a7260aebbcdb5 *./data/out.yuv
 stddev:  1.89 bytes:7602176
-108cb3071067f24571b2e5f0f5d4b234 *./data/a-odivx.avi
-ff7ddb57d9038b94f08c43bae7e1329f *./data/out.yuv
-stddev:  5.28 bytes:7602176
+f17dc7346f5d1d4307ecf4507f10fcc6 *./data/a-odivx.mp4
+a59dce32cce7a30ab3570e3e6280ba37 *./data/out.yuv
+stddev:  5.28 bytes:7450624
 242a7a18c2793e115007bc163861ef4e *./data/a-huffyuv.avi
 dde5895817ad9d219f79a52d0bdfb001 *./data/out.yuv
 stddev:  0.00 bytes:7602176