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Transcoder + Dynamic Overlay + Server Side playlist


I want to acquire this type of sollution:

I have 10 incomming live streams, all 720p, all 10 are online and i want to combine them into 1 channel, switching one-by-one very 10 seconds to get 1 outgoing streams (some kindof mixed output).

This can be done using Server Side Playlist and Transoder AddOn and this works.

But now i need to extend it - i want to add to outgoing stream PNG overlays which will be visible ONLY on outgoing stream that is selecte. So:

10 incomming streams,

10 different overlays (1 incomming stream - 1 overlay)


CAM1  ---|
CAM2  ---|
CAM3  ---|------Transoder------->CAM1-OV1--->CAM2-OV2--->CAM3-OV3--->CAM4-OV4 (etc)
CAM4  ---|
CAMX ---|

So i need to switch transcoder overlay file based on server side playlist item.

What would be the best path?


You would need to use some custom code to do this but it should be fairly easy.

If you are using the Stream class to create the server side playlist then there is an interface that you can use to get a notification when the playlist switches. From here, you can switch the overlays on your transcoded output.

Look at the IStreamActionNotify interface in the API documentation included with the server download.

For changing overlays, see How to add graphic overlays to live streams with Wowza Transcoder AddOn


Hi Roger, Thanks for instructions. I got it and it works great. I have just a little “delay” when switching sources. I mean that there is a 0,5s difference between switching image and overlay. Where is the buffer?


EDIT - nobody… but i found an workaround by myself. I think that encoder buffers some fps before passing it so i had to buffer overlay also and that did the trick.