2-pass VBR MP3-encoding?

[oRBIT]

Why haven't anyone thought of creating a 2-pass MP3 encoder? I know there are ABR-modes in most mp3-encoders but a 2-pass MP3 encoder should be able to create even better results. Or?

[DJ Bobo]

Yeah, I also thought about it, but then I think it won't bring too much quality gain, since:
1) ABR is not that significantly better than CBR
2) the bitrate range is very small, so 2-pass won't really bring something. It's not like video where the bitrate can go 1000kbps and higher up and down.

[buba king]

you only need 2 pass for predicting the exact filesize :)

so VBR 32-320kbis/s is the best.. (maybe if its a movie with alot of music you'll need a higher min br)

btw.. go vorbis :P

[Doobie]

I haven't noticed any demand for 2-pass MP3. I have no need of it.

[Neo Neko]

2-pass vorbis would be good. As it is it does a good job. But I still think it could benefit from 2-pass. Xiph is gonna release the full Vorbis specs very soon. Any one want to give it a go? :)

[Antti]

I think the only benefit would be filesize prediction. VBR MP3 is essentially the same as "quality-based VBR". Video is different from audio, e.g. there isn't a psychoacoustic concept like "motion". So quality-wise 2-pass is unnecessary. If you know better, tell us! :)