The input but it isn't technically lossless. Lossless or nearly so: it should look the same or nearly the same as

A lower value is a higher qualityĪnd a subjectively sane range is 18-28. The range of the quantizer scale is 0-51: where 0 is lossless, 23 isĭefault, and 51 is worst possible. ffmpeg will recalculate the correct value automatically while preserving the aspect ratio. You just set one size – which is the height in this example – and use -1 for the other dimension. The scale video filter is for resizing the video. To get a 'visually lossless' quality, you can use: ffmpeg -i MyMovie.mkv -vf scale=-1:720 -c:v libx264 -crf 18 -preset veryslow -c:a copy MyMovie_720p.mkv Note that this video might not be playable on all devices or players: ffmpeg -i MyMovie.mkv -vf scale=-1:720 -c:v libx264 -crf 0 -preset veryslow -c:a copy MyMovie_720p.mkv Here is an example which should give you the highest quality video (I'm not speaking about the resulting file size).

How can I specify right bit rate for video stream, and left all other stream copied pristine? I tried to convert it to 720p with ffmpeg: ffmpeg -i MyMovie.mkv -r 60 -s hd720 MyMovie_720p.mkvīut I there is significant quality loss because bit rate decreased from 32.3 Mbps to 2.8 Mbps. I stack with my high quality movie: 1080p with 60fps.

Ffmpeg resize mp4 to 720p