[MPlayer-users] Slow playback of x264 video in mkv

[Fredrik Eriksson]

Fredrik Eriksson wrote:

> So, I created a x264 video with mplayer using the following command:
>
> mencoder-cvs -dvd-device koikoi7.dvd2.real.iso dvd://1 -chapter 1-1 
> -ofps 24000/1001 -vf pullup=::::1:,softskip,hqdn3d=4:2:2 -nosound -ovc 
> x264 -of rawvideo -x264encopts 
> subq=6:frameref=7:me=3:4x4mv:bframes=4:b_adapt:b_pyramid:qcomp=0.7:keyint=300:8x8dct:pass=3:bitrate=1400 
> -o koikoi7.intro.x264.h264
>
> then I muxed the video to a mp4 container:
>
> MP4Box -fps 23.976 -add koikoi7.intro.x264.h264 koikoi7.intro.x264.mp4
>
> the video plays just fine with mplayer-cvs, with about 20% CPU usage.
> But then I mux it to a mkv container:
>
> mkvmerge -o koikoi7.intro.x264.mkv --timecodes 1:timecode.tmc 
> --vtracks 1 koikoi7.intro.x264.mp4 -a 0 koikoi7.intro.audio.ogg
>
> now the video playback is too slow and jaggy, the audio gets quickly 
> out of sync, although the CPU usage is about the same as with the mp4 
> file. I tried the file on my laptop, and the special build of ffmpeg 
> included in CCCP (http://cccp.kickassanime.org/) could play the file 
> just fine, so it's most likely not a problem with the file.
>
> does anyone know what the problem might be?

It appears that it's the b_pyramid option that is the culprit here, the 
same file encoded exactly the same way, except for the b_pyramid option 
plays just fine. Well, this solves the problem for me, but it might be 
something for the devs to look in to.

Fredrik Eriksson