Please can you help.
I have installed the correct packs into Audacity to recognise MP4 files and have been using this no problem to extract audio from YouTube downloads. However, when im downloading from Vimeo and import into Audacity, no waveform shows and no playback happens, however no error message shows. This only happens when i download a file from a video that was LiveStreamed and not recorded and uploaded to vimeo, however the file types are the same (MP4) which is confusing.
Any help would be greatly appreciated.
Maybe the file is DRM protected. Audacity does not support DRM (https://en.wikipedia.org/wiki/Digital_rights_management)
Thank you for your answer but ive checked this and its not the case
MP4 video doesn’t necessarily contain MP4 audio but Audacity with FFmpeg can decode most audio/video formats.
I assume you get audio when you play the downloaded file?
You can check and compare the file to one of your “good” YouTube files with [u]MediaInfoOnline[/u].
If you can play the file (with audio) with [u]VLC[/u] - [u]VLC HowTo/Extract audio[/u]
Thank you @DVDdoug
Using your method above i have noticed a different in file format. Youtube Live videos which audacity handles no problem shows format:MPEG-4 whereas Vimeo is showing Format:dash… Does anybody know if this can work with Audacity?
In VLC, start playing the file, then pause playback.
While playback is paused: “Tools > Codec information” - what does it say?
It comes up with 2 lots of info under 2 headers, “stream 0” and “stream 1”
Have a look at the image i’ve attached
What does VLC show for an MP4 that does work in Audacity?
There’s clearly something odd about the MP4s that don’t work - if we can figure out what that is, then we may be able to come up with a convenient workaround.
Have you tried playing those files in other apps?
My guess is that they won’t play correctly in any apps that use FFmpeg.
Yes this is the one that works, which is a live stream downloaded from youtube
Unless it’s just cropped from the bottom of the screen, the working one doesn’t use the SBR extension.
A quick Google search suggests that FFmpeg’s support for SBR is limited (only works with some frame lengths and not others).
Were you able to extract working audio from the “bad” MP4 using VLC? If so, then that may be your best workaround.
When converting through VLC it actually produces a readable file in Audacity, which is a great work around.
Thank you all so much for your help
Glad you have a usable workaround
Just for info:
At some point in the future there will be an updated FFmpeg for Audacity (I don’t know when). When that is released, it “may” fix the problem so that you won’t need to use the workaround.