[Libav-user] [FFmpeg-user] "Smoothing" RTSP over wlan

[Michael Fritscher]

Good morning,

thanks for your answer! My comments are inline.

On 27.06.2018 01:31, Carl Eugen Hoyos wrote:
> 2018-06-25 9:15 GMT+02:00, Michael Fritscher
> <michael.fritscher at telematik-zentrum.de>:
>
>> Scenario: Using RTSP over wlan to get video from a webcam,
>> using the lib itself.
> Sounds like wrong mailing list:
> http://ffmpeg.org/contact.html#MailingLists
Oh, sorry, somehow missed this. Subscribed & changed :-)
>> the WLAN has the characteristic to "pause" for e.g. 300 ms,
>> and send all the data at once. This makes the stream not
>> exactly smooth. Is there a way to tell the libav to buffer / wait
>> 500 ms and let the lib smooth it itself (bei e.g. using the
>> embedded timestamps)?
> I don't think this would be very useful, fast delivery is typically
> expected.
In my case, 300...500 ms more delay is acceptable if then the stream
doesn't stutter any more. In addition to stutter, sometimes I get
messages of "need to consume buffer now" (which is a sign that packets
are delayed too much) - in such cases I get even picture distortions.
>> Or must I smooth it myself (by buffering the pictures - which
>> needs a lot of memory - 25/2*1280*720*3 = round about = 35 MB).
> You could buffer a few input frames.
Yes, this is one of the options, but I would like to avoid it, because
it needs much memory (the mentioned 35 MB - multiple times as I work
with 3-4 streams at the same time). I hoped that I can instruct the lib
to buffer the compressed packets, which needs much less memory. I could
try to implement a proxy as well, but this sounds like much work...

Best regards,
Michael Fritscher

-- 
ZfT - Zentrum für Telematik e.V.
Michael Fritscher
Magdalene-Schoch-Straße 5
97074 Würzburg
Tel: +49 (931) 615 633 - 57
Fax: +49 (931) 615 633 - 11
Email: michael.fritscher at telematik-zentrum.de
Web: http://www.telematik-zentrum.de

Vorstand:
Prof. Dr. Klaus Schilling, Hans-Joachim Leistner
Sitz: Gerbrunn
USt.-ID Nr.: DE 257 244 580, Steuer-Nr.:  257/111/70203
Amtsgericht Würzburg, Vereinsregister-Nr.: VR 200 167