Add on24 downloader

[chbndrhnns]

Checklist

• I'm reporting a feature request
• I've verified that I'm running youtube-dl version 2020.03.24
• I've searched the bugtracker for similar feature requests including closed ones

Description

ON24 is used for online trainings like from the O'Reilly learning platform. Replays are available after the training but it seems they cannot be downloaded. I'd like to ask for a download functionality.

[VioletLightning]

@chbndrhnns please change the label to "site-support-request"

[VioletLightning]

@chbndrhnns you need to find stream.mpd file using chrome developer tool.
then use the command
youtube-dl -f bestvideo+bestaudio https://dashod.akamaized.net/media/cv/events/XYZ/stream.mpd
you need ffmpeg for merging formats.
see this stackoverflow link
I've used this method and it works on on24 platform.

[chbndrhnns]

@VioletLightning thanks for sharing! If it's possible like that, I would not even need a native implementation.

[pietrask]

I think that the main issue there is that they are separating video with audio with actually slides.
Of course, they are providing pdfs, but it would be cool to have a video, audio with actual slides at a particular moment at the time