[Matroska-users] Re: Multiple AC3 tracks / Matroska Splitter

Christian HJ Wiesner chris at matroska.org
Wed Feb 11 20:08:52 CET 2004


Gonzalo Bermúdez wrote:

>I had the intention of using divx (with a high bitrate) to back up
>DVDs with all the tracks available in them. This way I compressed
>LOTR-Two Towers extended version, which has 6 AC3 and I wanted to keep
>them all. First I tried to use AVI 2.0 for this and I came across this
>problem: video started to stutter and CPU consumption was 100%. That
>would not happen if I just muxed one AC3 with the video. When I had a
>look at the filters being used I found out that there was an AC3
>filter opened per each AC3 track!!! That is simply crazy!!
>(decompressing 8 tracks at the same time + video). Later on I tried a
>MKV file muxed with mkvmerge with the same results.
>
>I guess this is not the AC3 filter's fault but rather a deficiency in
>the AVI and Matroska splitters: they should have the possibility of
>manually/automatically (default in the stream) select what channels to
>demux (not to demux them all by default - although that could be
>useful with multiple hardware outputs). I any case can you give me
>some information about it?
>
You need a good player like TCMP or Zoomplayer with a built in stream 
switcher. The opened ac3 decoders are paused and will not consume CPU 
power this way. Only stupid Windows Mediaplayer doesnt have such a 
stream switcher and will try to decode all present audio tracks at the 
same time.

Christian




More information about the Matroska-users mailing list