hi, maybe this should go to the ffmpeg list... i uploaded the file mpeg4-vop-not-coded.avi (1MB) to mplayerhq/MPlayer/incoming. it's encoded with xvid, and it works fine if i specify -vfm xvid. (i have xvid-1.0.0-beta3 here). but if i start it normally (-vfm lavc), then: 1. visually: if there is some movement in the video (basically like scrolling the background), then it's not smooth. 2. output: mplayer outputs a warning: [mpeg4 @ 0x852d050]vop not coded approximately 4x every second. mplayer and libavcodec are from CVS today. mplayer log attached, is this a problem in lavc, or the video was encoded with another shouldnt-use-this-version-for-anything-but-testing xvid? gabor