[FFmpeg-devel] [RFC] AAC bsf and rtp/rtsp

Luca Barbato lu_zero
Thu Sep 9 16:44:23 CEST 2010

On 9/9/10 4:19 PM, Michael Niedermayer wrote:
> On Thu, Sep 09, 2010 at 04:16:41PM +0200, Luca Barbato wrote:
>> On 9/9/10 3:16 PM, Michael Niedermayer wrote:
>>> On Thu, Sep 09, 2010 at 03:08:33PM +0200, Luca Barbato wrote:
>>>> On 9/8/10 6:28 PM, Ronald S. Bultje wrote:
>>>>> That nice solution isn't completely impossible to implement, is it?
>>>> The simplest thing is passing the bsf in the context, anybody against that?
>>> until the problem has been explained i wont accept any solution to code i
>>> maintain
>>> the initial mail of this thread is so terse and full of grammer errors i
>>> have no idea at all what you talk about
>> looks like that a stray "is" was left while I was rewriting the
>> sentence, sorry.
>> Anyway:
>> - in order to produce the sdp lines for aac we need the aac extradata.
>> - adts stream do not provide extradata
>> - the bsf filter to reformat aac to asc would provide the extradata.
>> - because how bsf works in the extradata would be updated once it starts
>> to output packets.
>> ffmpeg -i s.aac -acodec copy -absf aac_adtstoasc -f rtp rtp://l:port
>> Won't work even if it should.
>> To fix it the simplest way would be having the av_find_stream_info aware
>> of the bsf in use so they will be called at the same level of the
>> parsers, giving a consistent result.
> the AVCodecParser.split() function exists to extract extradata from the
> packets at av_find_stream_info() level

So you'd suggest to use the extradata extraction logic there 
independently from the bsf presence?


More information about the ffmpeg-devel mailing list