CasparCG Server version 2.2 Dolby E destroy


I have a one question, maybe someone has similiar problem. On my one decklink 12G card, input is singal SDI with Dolby E and I’m using command PLAY 1-2 DECKLINK DEVICE 2 FORMAT 1080i5000. Everything is ok on the second card as output, but if I change a source input with Dolby E or without (example: DeEncoder 1 to DeEncoder 2). Audio with Dolby E is destroyed and one solution to this is execute command STOP 1-2 DECKLINK DEVICE 2 FORMAT 1080i5000 and next PLAY 1-2 DECKLINK DEVICE 2 FORMAT 1080i5000, generally take off input signal from casparCG channel- layout. Is any other solution to avoid ruined audio when input signal is switched ??.

Thanks for any suggestions.

Have a nice day.

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When you STOP and PLAY does that simply cause the downstream Dolby E decoder to disable itself? And does it just stay on when you just change the audio input without STOP and PLAY? I think the issue here is that the decoder should disable itself as soon as it detects that Dolby E stream is no longer present, but I don’t have experience with Dolby E so I don’t know if it’s standard behavior or something that it can do.

CasparCG (and the Decklink cards) don’t support Dolby E as such, they just passthrough the data as-is and that your setup works is coincidence/byproduct of how Dolby E is designed. I’m pretty sure that mixing Dolby E and regular audio on the same audio transmission lines is not something Dolby recommends, since pushing Dolby E down a regular audio path can be damaging. I think it is quite likely that it’s just not something that the Dolby E decoder can actually support.

What kind of workflow are you trying to achieve here?

Are you trying to mix two decklink inputs with Dolby E audio channels and output them to a single channel?

If that’s the case you can’t. They are digital tracks encoded in two-channel analog audio (just like how Dolby Surround with Dolby ProLogic works, but digital). If you mix the analog audio of both, the bit stream is corrupted by each other so the decoder won’t treat it as a Dolby E stream and would play it as an analog stereo track (please lower your speakers’ volume :sweat_smile:)
To archieve that (mixing them in CasparCG) you would need to decode the streams to multichannel audio before it gets to the Decklinks.


synchronizer before DE ENC solved problem.