TOOL » FFMPEG » VIDEO
Vp9
Overview
Open source & royalty-free video codec for WebM.
libvpx-vp9
For a full list of options, run ffmpeg -h encoder=libvpx-vp9.
| Option | Description |
|---|---|
-cpu-used | [0; 5] Quality-speed tradeoff. Lower is slower. Usually use 0, or 1 if in a hurry. |
-crf | [0; 63] Constant Rate Factor, where 0 is best quality (not lossless) and 63 is worst quality possible. Use -b:v 0 to disable Constrained Quality mode. |
-passlogfile | Set two-pass log file name prefix to prefix (final name becomes PREFIX-N.log). |
-row-mt | Enable row based multi-threading. Improve speed by about 50%. |
-tune-content | Tune content type. Use screen for screen capture content, film for film content (improves grain retention). |
An example of overriding -passlogfile in fish:
fish
set timestamp (date '+%s')
-passlogfile /tmp/ffmpeg2pass-$timestampConstant Rate Factor
Two pass is recommended.
shell
ffmpeg -i input.mp4 -vcodec libvpx-vp9 -r 60 -b:v 0 -crf 42 -tune-content screen -pix_fmt yuv420p -pass 1 -cpu-used 0 -f null /dev/null
ffmpeg -i input.mp4 -vcodec libvpx-vp9 -r 60 -b:v 0 -crf 42 -tune-content screen -pix_fmt yuv420p -pass 2 -cpu-used 0 output.webmNote: Use -pix_fmt yuv420p to increase compatibility with mobile devices.