Create different qaulities for my manifest with only mp4box

Question

I asked a question on slack on why the quality and bitrate of my dash video wasn't changing and I got this response: You only have one quality in your manifest. there is no way for the player to choose a different one You only have one quality in your manifest. there is no way for the player to choose a different one

So how can I create different "qualities"?

I have a mp4box command like:

MP4Box -dash 2000 -profile dashavc264:live -bs-switching multi -url-template whatever.mp4#trackID=1:id=vid0:role=vid0 whatever.mp4#trackID=2:id=aud0:role=aud0 -out whatever.mpd

Would it be possible to create different "qualities" with only mp4box or would I have to create the same video with different resolutions with something like ffmpeg and then feed them into the inputs to the command above?

Answer 1

GPAC contributor here. Since v0.9, GPAC has introduced a new architecture that allows to transcode by leveraging FFmpeg.

Example (forced intra period of 2 seconds):

MP4Box -dash 2000 -profile dashavc264:live -out session.mpd source.mp4:@@enc:c=avc:fintra=2

Edit: since 2020/09/29 multi-encoding is possible

MP4Box -fgraph -dash 2000 -profile dashavc264:live source.mp4:@ffsws:osize=160x120@enc:c=avc:fintra=2:b=100k:#Representation=1@@ffsws:osize=320x240@enc:c=avc:fintra=2:b=200k:#Representation=2

Please let us know if you have any questions!