The quest for batch conversion

[ku71]

I am looking for an automated way to convert the files produced by the PVR250 to one of the newer mpeg-4 based formats. I basically want to be able to drop files in a directory, wait a day, and retrieve the converted files. I am not (very) concerned with the file format, whatever works.

This is what I have tried:

Windows Media 9: Comes with a batch encoder, which I run like this

start /low cmd /k cscript.exe "c:\program files\windows media components\encoder\wmcmd.
vbs" -input d:\Video\Conversion\In -output d:\Video\Conversion\Out -v_mode 3 -v_bitrate 10000000
-v_preproc 1 -a_mode 2 -a_setting Q75_48_2

Caveat: Error opening mpeg2 files. I can work around this by playing the file simultaneously with a dvd player software. (but that's not automated)
Very slow conversion speed.

VirtualDub/DivX: Error opening files. (packet sync error)

ulead video studio demo: Has a batch mode, but no support for WM9. Hangs when opening dialog to choose codec for AVI format
Too expensive.

Dr. DivX/DivX: Has a batch mode. Sounds promising but does not have a command line mode.

[mlar]

ffmpeg. It works great. I use it on my slow EPIA M-9000 to convert MPEG-2 files into MPEG-4. On my EPIA it takes about 1 hour to convert a 30 minute show to MPEG-4.

http://ffmpeg.sourceforge.net/

You might have to write some shell scripts to do the batch processing, but since it is a command line application, it shouldn't be much of a problem.

[ku71]

Interesting, thanks :-)

What are the settings you are using? I tried this, however despite the generous bitrate the video dissolves into blocks occasionally (during fast motion).

$ ./ffmpeg.exe -i /cygdrive/e/in.mpg -vcodec mpeg4 -b 1200 -g 300 -bf 2 -s 480x360 -acodec mp3 -ab 128 /cygdrive/e/out.avi

[mlar]

Try adding a -hq on there for starters. I do my transcoding to very low resolutions (to be watched on my PocketPC), so I haven't really spent too much time on the parameters. Initially I did some testing with higher resolutions, and I believe it was the motion compensation settings that was the key. I know too little about MPEG-4 to be of much help though. ffmpeg should also be able to handle multipass encoding, which should help with fast moving scenes.