I can't seem to understand how to make the conversion lossless (or at least visually lossless)? The outputs have some fast moving parts at times, and the output would become blocky; I would like to keep it as lossless as possible, while still maintaining some compression. What would I have to tweak at the command line? Thanks you~
ffmpeg -c:v libvpx-vp9 -i in.webm -c:v libvpx -vf scale=400:416,hue=h=45:s=1 -auto-alt-ref 0 out.webm
According to FFmpeg Wiki: VP9, "two-pass is the recommended encoding method for libvpx-vp9 as some quality-enhancing encoder features are only available in 2-pass mode". Example of your command:
The CRF value can be from 0–63. Lower values mean better quality. Recommended values range from 15–35, with 31 being recommended for 1080p HD video. For more info see Google - Getting Started with VP9.