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Date: Fri, 3 May 2024 10:47:19 +0900
From: Mark Brown <broonie@kernel.org>
To: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Takashi Iwai <tiwai@suse.de>,
	Sebastian Fricke <sebastian.fricke@collabora.com>,
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Subject: Re: [PATCH v15 00/16] Add audio support in v4l2 framework
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On Thu, May 02, 2024 at 10:26:43AM +0100, Mauro Carvalho Chehab wrote:
> Mauro Carvalho Chehab <mchehab@kernel.org> escreveu:

> > There are still time control associated with it, as audio and video
> > needs to be in sync. This is done by controlling the buffers size=20
> > and could be fine-tuned by checking when the buffer transfer is done.

=2E..

> Just complementing: on media, we do this per video buffer (or
> per half video buffer). A typical use case on cameras is to have
> buffers transferred 30 times per second, if the video was streamed=20
> at 30 frames per second.=20

IIRC some big use case for this hardware was transcoding so there was a
desire to just go at whatever rate the hardware could support as there
is no interactive user consuming the output as it is generated.

> I would assume that, on an audio/video stream, the audio data
> transfer will be programmed to also happen on a regular interval.

With audio the API is very much "wake userspace every Xms".

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