On Sun, Oct 30, 2022 at 11:21 PM Oneric <one...@oneric.de> wrote: > On Sun, Oct 30, 2022 at 14:10:29 +0100, Lynne wrote: > > Sep 27, 2022, 23:06 by gustav.grus...@gmail.com: > > > > > Implements support for 2-pass CRF and 3-pass VBR by implementing > > > reading and writing of stats file, and passing the pass number on > > > to the encoder. For 3-pass VBR, the first pass should be run with > > > '-pass 1', the second with '-pass 3' and the third with '-pass 2'. > > > > > > [...] > > > > 2-pass doesn't seem to work, the encoder complains it's not the final > pass. > > fwiw, 2-pass CRF and 3-pass VBR work for me on a short sample with this > patch applied on top of 882a17068fd8e62c7d38c14e6fb160d7c9fc446a and using > SVT-AV1 1.3.0. > > Ah good to hear the patch works also with SVT-AV1 1.3.0. I hadn't found the time to check this.
> I'm not sure if 2-pass VBR is supposed to work, though I didn't look into > it too much. SVT-AV1 docs only mention 3-pass VBR[1] afaict and while > requesting output already in the second pass (`--pass 2` for SvtAv1EncApp > and `-pass 3` for patched ffmpeg) "works", the result misses the targeted > overall bitrate even more than singlepass VBR. > My understanding is also that SVT-AV1 does not support 2-pass VBR, like you say there is no mention of 2-pass VBR in the docs. The rate-control appendix gives some details about how the 3-pass VBR works, as far as I understand the second pass uses CRF so makes sense that it would miss the target bitrate. https://gitlab.com/AOMediaCodec/SVT-AV1/-/blob/master/Docs/Appendix-Rate-Control.md#vbr-rate-control-flow cheers, Gustav _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
