Input with multiple audio streams

Wowza Streaming Engine
1

Hi,

Is there any plans on the roadmap to facilitate an input stream with multiple audio languages, to encode the video once and then have multiple output streams, each with a different language audio? We’ve got an input stream with 5 languages and it seems a shame to transcode the video 5 times just to achieve different audio tracks.

Thanks

2

Yes, take a look at this article:

https://www.wowza.com/docs/how-to-select-audio-data-and-or-video-channel-from-a-multi-channel-mp4-file-by-using-imediareaderactionnotify

And these:

https://www.wowza.com/docs/how-to-select-mpeg-ts-stream-by-program-id-and-also-audio-language-by-pid

https://www.wowza.com/docs/how-to-control-video-and-audio-pid-and-streamids-for-outgoing-mpeg-ts

Richard

3

You can do this but you need to ingest and encode the stream separately for each video language combination. Turn on udp port sharing and use query params to select the video/audio pid for each combination.

Charlie

4

Sorry, I overlooked the category. I don’t think Wowza Transcoder supports multiple tracks at present.

Richard

5

You would have to do multiple transcodes, one for each language you select in a .stream file or alias rule

Richard

6

No, it hasn’t.

Richard

7

Hi Richard,

Those links don’t seem to quite fit the bill. I have an incoming UDP stream with one video track and then N languages (let’s say english, french, and audio described), what I want to happen is for the transcoder to take the video track and the 3 audio tracks in, transcode them all and then be able to access each language independently e.g. rtmp://localhost/live/test.stream_360p_en, rtmp://localhost/live/test.stream_360p_fr, rtmp://localhost/live/test.stream_360p_ad I don’t believe this is currently possible?

Thanks

8

Hi Charlie,

Would this mean we’d have to transcode the video multiple times, or would we get away with transcoding the video once? (which is what I’m trying to achieve, to save CPU resources)

Thanks

9

Hi Charlie,

Would this mean we’d have to transcode the video multiple times, or would we get away with transcoding the video once? (which is what I’m trying to achieve, to save CPU resources)

Thanks

You would have to do multiple transcodes, one for each language you select in a .stream file or alias rule

Richard

This hasn’t changed since January, by chance, has it?

10

If I were to use PassThru for the transcoder audio settings and the inbound transport stream had two audio PIDs, would both pass through? If not, which PID would get selected? The first one defined in the PMT?