[FFmpeg-devel] [PATCH] libavdevice/decklink: 32 bit audio support

Douglas Marsh ffmpeg at dx9s.net
Tue Oct 17 22:24:18 EEST 2017

On 2017-10-17 06:22, Dave Rice wrote:

> I don't see there to be an AV_OPT_TYPE_ENUM. Could you point out how
> this works from an example? Alternatively since the decklink sdk only
> supports 2 bit depths (16 and 32), I could use a boolean here if that
> makes more sense.
> Dave Rice

I am unsure about the AV_OPT_TYPE_ENUM as well so can't answer that. I 
would not use a boolean, even tho the audio word/sample sizes will 
probably never change from those two offerings. As stated in previous 
recent message/thread, from what I know about my card, it only has a 
24-bit ADC/DAC for audio and the 16-bit modes are either truncated or 
dithered in hardware or drivers. They might come out with higher end 
hardware that captures 32-bits PCM at some later date, they will have an 
additional defined constant which would require converting the boolean 
back into an int what your patch currently has (int I believe it was).

I will try the patch out when I can as it is something I want for two 
reasons (higher quality and see if it solves an audio glitch that 
occasionally pops up during capture, difficult to reproduce -- happens 
with their reference capture software under Linux as well so think it is 
hardware issue with HDMI splitter I have).

--Doug (dx9s)

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