choppy playback of mono audio in ogm files (w/ 0.9.8.6 filter)

[canadian_fbi]

i saw that in the 0.9.8.6 filters, tobias fixed the bug that caused mono vorbis audio to play back too fast in ogg files. however, i just did a test encode of an iron chef episode with mono audio and had some choppy playback at points. here's a link to a short (1.5 mb) clip that demonstrates some of the problems:
http://www.disconnect.net/temp/choppy.ogm
it wasn't a huge problem in parts, but it was bad enough at times to be very annoying. it's also a worse problem in the clip than it was in the movie (i cut the audio and video separately using virtualdub and vcut and remuxed them), skipping three times in the clip while only once in the same part of the original.

i know it isn't an audio or video problem, because the originals play just fine, and i encountered the problem with both the xvid and divx filters and with different levels of postprocessing. i think maybe just a little bit more tinkering needs to go into the mono audio playback.

oh, and playing it with stereo audio fixed the choppy playback, which is what led me to believe it was a mono bug. the audio quality was a lot better with the mono file though, so i really don't want to have to use stereo, since it really isn't needed for an episode of iron chef ;)

[MaTTeR]

OMG! Here I thought I was the only one that watched the show:D

I downloaded the clip and it definitely has playback issues with 4 different players.

[canadian_fbi]

iron chef is actually what got me started using divx, about five months ago. :) i've got 32 episodes now, three to a cd. let me tell you though, iron chef'll take the pepsi challenge against any movie you can come up with as far as encoding difficulty is concerned. especially for me, because i'm recording off a cable line that's being split four different ways up here among my roommates and myself. so in addition to the noise in the capture, you've got about half the show being rapid movement with handheld cameras, guys running around kitchen stadium, things boiling, frying, flames going up, just total chaos. it's all i can do to get good quality at 320x240, though i'm going to try some new techniques tomorrow. it's getting better as i get some more experience.

but this is a bit off the topic, so i digress :) let me just say though that it would be great if i could switch to doing this from avi to ogg, since vorbis audio is sounding great here at 54 kbps, and xvid + vorbis is really looking promising and delivering exceptional quality already.

[MaTTeR]

That's a good point. Iron Chef as a source looks to be a very hard core encode.

Yes Vorbis is really impressive to say the least. It seems like you could maybe go lower than 54kbps on the quality. I mean I've been getting away with using around 65-70kbps for some DVD source material(Non-Action movies of course). In the Vorbis developer mailing list a thread is entitled "Ogg Vorbis to good!". The user makes a good point about the 0.01 q level still sounding to good. q-0.01 seems to be the bottom but they could possibly fix this in the upcoming RC4.

[canadian_fbi]

i can probably go a bit further, but i'm sort of a stickler for audio quality. i've been encoding mp3s since the days of winamp 1.0, and i'm much more sensitive to artifacts in audio than video i think. also, i think the increase in quality you get from going from 40 to 50 kbps in audio is much more significant than what you get from going from 680 to 690 in video. for me, vorbis in divx movies is just as much a way to increase quality as it is to reduce file size.

[Neo Neko]

I had one or two stutters but it was very watchable. Though I think I had my volume up quite a bit! My ears are still ringing a bit!