[FFmpeg-devel] [PATCH] avformat/avienc: add muxer option "write_channel_mask"

Tobias Rapp t.rapp at noa-archive.com
Thu Sep 10 15:28:54 CEST 2015

On 10.09.2015 14:57, Derek Buitenhuis wrote:
> On 9/10/2015 1:25 PM, Tobias Rapp wrote:
>> My use-case is handling recorded AVI files which have an
>> unknown/empty/unsupported channel layout. Instead of writing the guessed
>> channel layout into the output file, using "-write_channel_mask off"
>> allows to write an empty channel mask instead.
> Are such files even valid?

I guess so as the docs at [1] say in chapter "Details about dwChannelMask":

"If, for example in a multi-channel audio authoring application, no 
speaker location is desired on any of the mono streams, the 
dwChannelMask should explicitly be set to 0."

BTW: I just noticed that FATE is failing after applying the patch so 
I'll need to take a closer look and update the patch before it can be 


Link [1]: 

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