Dan, I added a new module: avsync. It has one producer and one consumer. The producer generates a stream with a classic blip/flash pattern. The consumer attempts to detect the blip/flash and calculate the audio/video sync. The consumer will report the caluclated lipsync in milliseconds. A positive number indicates that audio leads video. A negative number indicates that audio lags video.
The module can test itself: melt -silent -profile atsc_720p_30 blipflash -consumer blipflash avsync = 0.00 Obviously, 0 is perfect sync. It is interesting to round-trip the pattern through some various encodings: melt -profile atsc_720p_30 blipflash -consumer avformat:test.avi melt -silent test.avi -consumer blipflash avsync = -23.02 melt -profile atsc_720p_30 blipflash -consumer avformat:test.mpg melt -silent test.mpg -consumer blipflash avsync = -10.02 melt -profile atsc_720p_30 blipflash -consumer avformat:test.mkv melt -silent test.mkv -consumer blipflash avsync = 0.00 melt -profile atsc_720p_30 blipflash -consumer avformat:test.mov acodec=ac3 melt -silent test.mov -consumer blipflash avsync = -5.33 melt blipflash -consumer libdv:test.dv melt -silent test.dv -consumer blipflash avsync = -40.00 A sync worse than +/-3ms is pretty bad, in my opinion. Some of these might be worth looking in to. Anyway, the module is obviously up for debate. Let me know your thoughts. I can add, modify or delete as appropriate. ~Brian ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_feb _______________________________________________ Mlt-devel mailing list Mlt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mlt-devel
