[FFmpeg-devel] [PATCH 5/7] avformat/mpegts: add s337m support

[Michael Niedermayer]

Hi Kieran

On Fri, Dec 13, 2024 at 01:37:34AM +0000, Kieran Kunhya via ffmpeg-devel wrote:
> On Fri, 13 Dec 2024, 00:39 Michael Niedermayer, <michael at niedermayer.cc>
> wrote:
> 
> > Hi
> >
> > On Thu, Dec 12, 2024 at 12:54:29PM +0000, Nicolas Gaullier wrote:
> > [...]
> > > This is a significant work with some weird things like dealing with a
> > truncated sample rate
> > > and droping one sample from time to time to keep sync. And with no active
> > > maintainer of the dolby_e decoder, so that won't help.
> >
> > why would the decoder need to drop a sample from time to time ?
> > the timestamps on audio should be enough.
> >
> > Yes it would mean the samplerate and the timestamps and the number of
> > samples
> > would mismatch but that can be corrected by a resampler following after the
> > decoder or by other means, none of which really are specific to this.
> > Recording audio with cheap hardware is unlikely to have its sample rate
> > synchronized to an atomic clock either.
> >
> > but maybe i misunderstand something ?
> >
> > thx
> >
> 
> One of the features of Dolby E is output is resampled to a 1602, 1601,
> 1602, 1601, 1602 cadence ( 48000*5*1001/30000 = 8008)  number of samples so
> that it doesn't drift relative to 29.97 video.

thank you for explaining


> 
> I'm not really sure how an atomic clock is relevant.

its not, i guess i understood "droping one sample from time to time"
litterally. (which really would be the wrong thing to do)

What was meant IIUC now, is that the output is segmented in 1601.6 sample
packets on average, with a mix of 1601 and 1602 sample packets to reach
that average.

thx

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

If the United States is serious about tackling the national security threats 
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