On Mon, 27 Nov, 2023, 7:32 am Aditya Dandavate, <adityadandavat...@gmail.com> wrote:
> On Mon, 27 Nov, 2023, 4:16 am Ferdi Scholten, <fe...@sttc-nlp.nl> wrote: > >> What is the quality rate control when encoding in VBR mode ? >> > I get message : >> > >> > Svt[warn]: The input q value is ignored in vbr mode 20 when I set the >> -crf >> > to 20 when enabling the -svtav1-params rc=1. >> > When I set -qp 20, the conversion fails. >> > >> > Which mode to set quality when encoding in VBR mode ? >> > >> vbr encoding does not support quality setting, you get the maximum >> quality that fits the specified bitrate and it uses lower bitrates if >> possible if the content does not require high bitrates. >> >> >> If you want CRF with a cap on the bitrate you need to set mbr >> (MaximumBitRate) >> >> -crf 20 -svtav1-params mbr=5000k >> >> You do not need to specify rc=0, because that is default. You also do not >> specify -b:v 5000k >> >> >> Or if you want VBR >> >> -svtav1-params rc=1 -b:v 5000k >> >> No quality settings like crf or qp as they require rc=0 you can however >> set -qmin (default 1) and -qmax (default 63) >> >> >> OR if you want CQP >> >> -qp 20 -svtparams aq-mode=0 -b:v 5000k >> >> qp only works when aq-mode=0 (default aq-mode=2) >> >> >> Hope that helps? > > Also, a quick question about Constrained Quality Mode: In VP9, we trigger it by combination of '-crf' and 'b:v' and the value of bitrate is must be non zero to trigger the mode. How to trigger it in libsvtav1 ? > _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".