Problems with DivX 5.1 and VirtualDub

[PrinceEndo]

I just downloaded the DivX 5.1 codec, and I encoded an anime DVD series (Record of Lodoss War OAV) using FlaskMPEG and the 5.1 codec. The episodes are encoded in one big chunk, and to split them I wanted to use VirtualDub. When I try to play the file in VirtualDub to get to the point to cut the episodes at, I get an error. I get the same error whether I use VirtualDub or VirtualDubMod. I have in the attached picture the error as well as the file information from VirtualDubMod. I don't know why it wants to decompress with XviD either. Any help would be appreciated. Thanks.

[setarip]

Use VirtualDubMod to scan for errors - and then "mask bad frames"...

[PrinceEndo]

The text at the bottom now states "43936 frames masked (909 frames bad, 43027 frames good but undecodable)" and when I hit mask frames it won't play. I don't really understand, because the file will play fine normally when I open it in a media player, and it will cut fine if I select "direct stream copy" and cut it, it just won't play in VirtualDubMod or VirtualDub.

[DrinkOrDie]

That is exactly what it is supposed to do when you hit "mask frames" and you then playback in Virutaldub. You see, mask frames basically causes Virtuadub to deal with the video as if those frames didn't exist. That way, it won't include bad frames that you masked, in the final output. It's like "virtual" deletion of the selected frames.

Understand that "masking" is not the same as actually cutting the frames out, that is why WMP plays the source fine. WMP isn't masking any frames. Masking only stops the frames from being processed in virtualdub.


AVI has what is called "Keyframes". If you delete (or mask) a keyframe, every frame in between to the next keyframe is still good, but cannot be processed because the keyframe records the differences between those "in between" (key)frames.

You have masked ALL of your keyframes. That's why you have good frames that can't be processed, and that's why you can't play the file after masking them. You must have at least one keyframe at the beginning of your video for it to be playable.

I highly doubt that all 909 of your keyframes (and only keyframes) are bad. I think the problem lies with trying to decompress DivX video with the Xvid codec, producing a false positive for bad frames.