youtube-dl: cant get compatible bestvideo+bestaudio for mp4

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Question

Problem: Can’t Get mp4 format with bestvideo+bestaudio Once i try doing youtube-dl.exe --merge-output-format mp4 URL it will download the MP4 format but with bad video quality I expect the command to download the bestaudio and video format but i cant get it working…

About this issue

Original URL
State: closed
Created 3 years ago
Comments: 16 (9 by maintainers)

Most upvoted comments

… What’s wrong with this one, though ? It gets both the best MP4 vid and the best M4A audio (FFmpeg/avconv required), and otherwise the best MP4 combination (which in this case is anything but best, but that’s YT’s fault, not ytdl’s):
youtube-dl -v -f "bestvideo[ext=mp4]+bestaudio[ext=m4a]/best[ext=mp4]" "4ukOvwQmJvE"

Yes, apart from “Windows” vs ‘POSIX’ shell quotes. your -f is an alternative way of asking for the selection specified by '(bestvideo+bestaudio/best)[ext!^=web]' in the command that I almost simultaneously posted.

In the first command you were asking to combine two video formats, and the list of alternative formats did not include any that were available. Had one been, you would then have got a message like ERROR: Both formats 399 and 399 are video-only, you must specify "-f video+audio".

Something like this (305/266/304/264/137/bestvideo[ext=mp4])+bestaudio[ext=m4a] would work if one were desperate to get one of the 5 listed formats when available, but the other formulations are simpler and more robust against site changes.

dirkf on Aug 19, 2021