MKV/H264 problems

[Alexstarfire]

Yea, I know there are a few threads about this, but none of them have helped me. I seem to have a rather interesting problem that I simply can't figure out. I have tried several ways to convert this MKV file, which has an h.264 video file, an aac audio file, and 2 .ass subtitle files. Naturally I've tried splitting the MKV to get all the files, which I have to do for the subtitle files anyway, and converting the video and audio separately then adding the subtitles. It seems that the video and subtitles are synced, but that the audio is messed up. Started off synced but then ends up off after just 20 seconds, which is when they first talk. I can't seem to get this fixed no matter what I try. I've used VirtualDub /w AVISynth and AVIDemux but to no avail.

I think it is worth noting that when I try to play the h264 file after extracting it from the MKV that it seems to skip and lag. Not sure why, but I feel it's not supposed to do that. Ohhh, and it's also worth noting that I've tried just doing direct stream copy in VirtualDub and still get the same issues. So it doesn't seem to be an actual conversion issue. Any ideas cause I'm stumped?

[Baldrick]

Is the MKV in sync before you try convert anything?

[Alexstarfire]

Yep.

[Alexstarfire]

Hmmm, after extracting the files from the MKV and using AVISynth to play them it seems that the audio is still off. I have no idea what that means or why the MKV works fine but isn't synced properly when they are split.

[poisondeathray]

convert to what format? why don't you just leave it?

might be vfr; not all containers will support that. avi doesn't.

[Alexstarfire]

I'm converting it so I can burn it to DVDs and play on my DVD player. Might be easier to set up my computer to my TV, but they aren't in the same room, I don't have the money for it, and it doesn't allow me to play my videos at other people's houses.

I'm trying to convert to AVI, XVID video and MP3 audio. It seems simple enough but I can't figure out this stupid audio problem for the life of me. Since it's not a conversion problem I have no idea what to do.

I've kinda of assumed it was either VBR or ABR audio, but it still doesn't explain why it won't sync when using AVISynth to just play the separate files. Also, after converting the audio to CBR it still is out of sync. I've tried multiple codecs, different conversions, etc.. but they all come out the same.

Hmmm, just looked at the timecodes for both tracks and it seems that one goes in increments of 33 while the other goes in increments of 21.3333. Seems like that would be a problem to me, is it? If so, any way to fix it?

[poisondeathray]

So your end goal is xvid/mp3/avi burned on a dvd so it can play on standalone dvd players?

If the timecode intervals are the same, it's cfr. If there is variability, it's vfr and you will never get it perfect for avi

Try converting using the container, when you demux you lose timing information and possible delays. If you are hardsubbing, just remove the subs only with mkvextract and use textsub(). Make sure you leave the video & audio intact inside the mkv container

e.g.
DirectShowSource("video.mkv")

Preview that avs in MPC to see if it is in sync first

[Alexstarfire]

I wish it was that simple, but I can't just convert the MKV since the audio is multichannel AAC. VirtualDub won't convert it because the source audio isn't mono or stereo and VirtualDubMod either converts it wrong or crashes depending on the settings. I'm thinking it might be a lot easier for me if I just go find a different version of this video on the net, though it's not something I want to do since I have tons of these types of video files to convert.

Sigh.... why in the hell is this so hard?

Ohh, and loading the AVS shows that it is synced. Though, I already knew the problem starts after I've demuxed the files.

[poisondeathray]

Sure you can. You can downmix the audio to stereo in the avs script, or through ffdshow's mixer.

If you don't want do it all manually, I think xvid4psp or megui can do this for you.

[Alexstarfire]

Actually, I finally figured out that's why it showed up as 6 channel audio in VirtualDub and only 2 channel in just about every other program. FFDShow was set to 5.1 surround sound. Anyway, even after changing that it still does the same thing. I ended up getting really desperate and using Mencoder on the MKV file itself. For some reason it'll convert it properly even though nothing else seems to. Of course I then have to go back and convert it using VirtualDub since I can't see a way to incorporate subs using Mencoder.

Whatever though, at least the damn thing plays properly now.

[Relayerman]

I have used WinAvi to convert the exact same file type as you and it did a wonderful job and everything in sync. It goes to DivX instead of Xvid because for some reason the Xvid quality is worse than Divx with just this software. Minor irritation.