How to recognize if a stream contains both video and audio OR contains just one of them

[Xinheng]

Hello,

I have a hls stream with with both video and audio and I have also a hls stream with only video. Instead of playbin, I use hlsdemux and tsdemux to play them. But for the two different cases, I have to construct two different pipelines.

The question is, is there any way to recognize the stream (if it contains both or just video) before I construct the pipeline in order to play it correctly? Thank you.

[Baby Octopus]

You can attach decodebin after hlsdemux and wait for the callback. You will get callback such as "pad-added" signal which will tell you the caps of decoded media

Alternatively, see if gst-discoverer helps you