Long conversion time from MKV to MP4 when downloading 2K VP9 file

[roenthomas]

The program functions normally, downloads the audio track first, then the video track, before combining them. It then takes the step of converting the mkv file to an mp4 file, and that's where this issue lies.

The conversion seems to take a long time. VP9 (and AAC for the audio) is a codec that is supported by MKV, WEBM and MP4 containers; a remux is all that is needed, rather than a conversion. This preserves stream quality and is also less taxing on the CPU.

On my own computer, using command line, I used the command: ffmpeg -i input.mkv -c copy output.mp4

The remux was completed in seconds. Currently, I'm at least 5 minutes into this conversion within uYou.

Perhaps this can be an enhancement to speed up changing of containers from MKV to MP4?