diff --git a/tests/ffserver.conf b/tests/ffserver.conf
index 3612843fae..1e7a685b93 100644
--- a/tests/ffserver.conf
+++ b/tests/ffserver.conf
@@ -57,7 +57,7 @@ FileMaxSize 100M
 
 # Fire up ffmpeg pointing at this stream
 
-Launch ./ffmpeg -v 0 -y -f pgmyuv -i tests/vsynth1/%02d.pgm
+Launch ./ffmpeg -v 0 -y -f image2 -i tests/vsynth1/%02d.pgm
 
 ACL allow localhost
 </Feed>