[FFmpeg-devel] AVCodec.supported_samplerates mostly null

Don Moir donmoir at comcast.net
Fri Jun 8 12:10:59 CEST 2012

----- Original Message ----- 
From: "Carl Eugen Hoyos" <cehoyos at ag.or.at>
To: <ffmpeg-devel at ffmpeg.org>
Sent: Friday, June 08, 2012 5:17 AM
Subject: Re: [FFmpeg-devel]AVCodec.supported_samplerates mostly null

> Don Moir <donmoir <at> comcast.net> writes:
>> Noticing that AVCodec.supported_samplerates is null
>> for all audio codecs except mp3 after avcodec_find_encoder.
> Patch probably welcome.

More like 50 to 60 patches. This was probably an oversite and maybe has to 
do with copying code samples, but it would probably have been easy to do if 
it was done when the codec was added to ffmpeg.

I am not sure if anyone knows now what sample rates are actually supported 
with the various codecs. Probably a first step would be to write a program 
that spits out the supported sample rates for each codec. Then those good be 
looked at in more detail.

I think also there may be many sample rates that are inherient to the codec 
but are not currently supported in ffmpeg. Generating a list of supported 
sample rates would also be good for documentation and to see what samples 
rates are not supported but should be.

for example, ogg/vorbis, wma, etc can do a variety of sample_rates / 
bit_rates that are not currently supported in ffmpeg and probably no one has 
a good feel why they aren't except maybe the person who put that codec into 

supported bit rates is probably another needed thing. so for each sample 
rate, list supported bit rates when that applies.

I could open a ticket on it and start producing supported sample rate lists 
to add to that ticket.

The above seems a reasonable way to start unless someone has a better idea. 
I will wait to see what the response is.

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