TOOL » FFMPEG » VIDEO
Av1
Overview
Open source & royalty-free video codec developed by the Alliance for Open Media (AOMedia). It seems to give better results than HEVC.
libaom-av1
For a full list of options, run ffmpeg -h encoder=libaom-av1.
| Option | Description |
|---|---|
-crf | [0; 63] Constant Rate Factor, where 0 is best quality (not lossless) and 63 is worst quality possible. |
-cpu-used | [0; 8] Quality-speed tradeoff. Lower is slower. HEVC slow ≈ 6-5, slower ≈ 3 |
-g | Keyframe interval. A keyframe is inserted at least every N frames, sometimes sooner. |
-row-mt | Enable row based multi-threading. Must have. |
-tiles | Set the number of tiles to encode the input video with, as columns x rows. May decrease encoding efficiency. Start with 3x3 and adjust acordingly to the chosen -cpu-used. Must have. |
Due to this issue, I recommend using -aom-params enable-warped-motion=0 to avoid the re-encoding process stopping in the middle because of an error. Will probably be fixed in v4.0.
For Constant Rate Factor (CRF), choose between One-Pass and Two-Pass.
One-Pass:
shell
ffmpeg -i input.mp4 -vcodec libaom-av1 -r 60 -crf 53 -cpu-used 2 -row-mt 1 -tiles 2x3 -g 600 -aom-params enable-warped-motion=0 output.mkvTwo-Pass (may give better results):
shell
ffmpeg -i input.mp4 -vcodec libaom-av1 -r 60 -crf 53 -cpu-used 2 -row-mt 1 -tiles 2x3 -g 600 -aom-params enable-warped-motion=0 -pass 1 -f null /dev/null && \
ffmpeg -i input.mp4 -vcodec libaom-av1 -r 60 -crf 53 -cpu-used 2 -row-mt 1 -tiles 2x3 -g 600 -aom-params enable-warped-motion=0 -pass 2 output.mkvlibsvtav1
For a full list of options, run ffmpeg -h encoder=libsvtav1.
| Option | Description |
|---|---|
-crf | [0; 63] Constant Rate Factor, where 0 is best quality (not lossless) and 63 is worst quality possible. |
-preset | [0; 13] Quality-speed tradeoff. Lower is slower. HEVC slow ≈ 6-5, slower ≈ 4 |
-g | Keyframe interval. A keyframe is inserted at least every N frames, sometimes sooner. |
-pix_fmt | Set pixel format. Only yuv420p yuv420p10le is supported. |
For Constant Rate Factor (CRF), choose the desired CRF and preset:
shell
ffmpeg -i input.mp4 -vcodec libsvtav1 -r 60 -crf 40 -preset 4 -g 600 -pix_fmt yuv420p output.mkv