[FFmpeg-devel] [RFC][PATCH] libavformat: add librist protocol

[Marton Balint]

On Mon, 22 Feb 2021, Paul B Mahol wrote:

> On Mon, Feb 22, 2021 at 8:27 PM Marton Balint <cus at passwd.hu> wrote:
>
>>
>>
>> On Mon, 22 Feb 2021, Paul B Mahol wrote:
>>
>> > On Mon, Feb 22, 2021 at 9:10 AM Gijs Peskens <gijs at peskens.net> wrote:
>> >
>> >> Hi, some feedback from one of the libRIST developers:
>> >>
>> >> Testing this patch (via diff found
>> >> on:
>> >>
>> https://patchwork.ffmpeg.org/project/ffmpeg/patch/20210126205145.20448-1-onemda@gmail.com/
>> >> ) I've noticed FFmpeg is not reading fast enough from the libRIST FIFO
>> >> buffer (which is limited to 1024 packets) causing it to overrun.
>> >> Unfortunately libRIST had a bug where it kept incrementing the buffer
>> >> counter indefinitely, this has now been fixed and it will log an error
>> >> whenever this happens (which is very often with FFmpeg).
>> >> FFmpeg will need to read the FIFO faster, by calling the librist_read
>> >> function more often. If that's not possible within the design of FFmpeg
>> >> the module can either:
>> >>
>> >
>> >
>> > Unfortunately some other devs disagree with initial patch and thus this
>> > issue.
>>
>> Could you pinpoint which change/discussion are you referring to here?
>>
>>
> Probably one that is about longer polling time..

I don't see how a larger polling time can cause such issue, unless 
something is very buggy. If there are queued packers in the fifo, 
rist_receiver_data_read should return immediately regardless of the 
polling time.

Regards,
Marton