Anyway, for this work I use the simple but very functional VirtualDub. VirtualDub lets me say "start here" and "stop there" and snip out a minute and a half of video without the time-consuming (and quality-destroying) re-encoding. It just grabs what's there, bit-for-bit (and creates new keyframes as necessary).

But VirtualDub is designed for AVIs with fixed bit-rate MP3 soundtracks. Kamichu! has been released so-far as an HDTV** Matroska file with AAC audio. Standard VirtualDub won't have a bar of it. VirtualDubMod, which has been patched to handle Matroska files, crashes violently on Kamichu!

I'm not that easy to stop, however. I used MKVextract to split the Matroska file into an XVID-encoded video-only AVI and a separate AAC audio file. Then I used All Converter to turn the AAC file into a raw WAV. Then I fired up VirtualDub again, and told it to load the video from the AVI and the audio from the WAV, and re-interleave them into a new AVI file and snip out this bit (the opening credits) and that bit (the closing credits) for me.

Which it did. And lo, the opening credits were very good. But the closing credits were teh suck, because the audio was hugely, and I mean hugely out of sync with the video, and the main reason that the closing credits of Kamichu! are cute is that they are in sync with the music. As you will see when I put them up for you to download. Via Bittorrent.

This caused a certain amount of puzzlement as it slowly dawned on me that not only were the audio and video out of sync, but that the problem became worse over time. Close examination indicated that even if they were in sync at the start of the clip, they were out by fifteen or twenty seconds at the end, which is a hell of a lot.

This, it turns out, is because the closing credits run at 30 frames per second, while the rest of the show runs at 24 fps. Why anyone would wish to do that I have no idea, but that is indeed what they have done. In the original video file it works just fine, but when I clip out the closing credits, it falls apart. But if I take that clip and tell it hey, you run at 30 fps... It works!

But you can't see it, because we have no bandwidth left.

* Between the anime fans and the bastard referrer spammers, the bandwidth well has run dry this month. I was planning to get another server to offload some of our stuff, but the hosting company seems to have run out as well.
** As it happens, it's really just up-converted anamorphic widescreen 704x480 video, not native 720p. It still looks pretty.

Posted by: Pixy Misa at 10:47 AM | Comments (3) | Add Comment | Trackbacks (Suck)
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