[Ekiga-devel-list] Incoming video in Ekiga

[Lorenzo Miniero <lorenzo miniero unina it>]

Hi all,

I'm writing this mail and not on -users since I think this will be of 
more interest to developers than users.

I'm developing a videomixing application and I'm using Ekiga to test its 
functionality with H.261. The mixing and composition, both based on 
libavcodec/libswscale, of more Ekiga video sources works fine (well 
fine... let's say it somehow works, to be a start), but I noticed a 
strange behavior when sending the mixed frames back to the Ekigas. All 
is done on 176x144 frames, which means that each Ekiga sends its own 
176x144 frame, and they receive back a 176x144 composed frame containing 
a mix of all the sources. However, when Ekiga receives the first mixed 
frame, the video window is resized to 352x288, even if only the top-left 
part (which is 176x144) is filled with the incoming frames, while the 
rest of the window remains empty, except for some garbage.

The strange thing is that, if before sending Ekiga the first mixed 
frame, I send it back a frame of it's own video, the window is not 
resized and the mixed video appears in a normal 176x144 window.
I don't know if it's a bug in Ekiga or if it's what I'm sending that is 
corrupt, which is why I've written you about it, since I really can't 
understand what could be wrong.

I've uploaded an example of what is sent to an Ekiga:

	* a Wireshark dump, http://confiance.sf.net/ekiga_wireshark.dump
	* and a RTPTools dump, http://confiance.sf.net/ekiga_rtptools.dump

both about 300k, which I hope can help you riproduce the scenario.
If you're interested you can use the rtptools dump to see how ffplay 
instead correctly understands the size of the frames:

	rtpplay -s 6666 -f ekiga_rtptools.dump /6668 (sender)
	rtpdump -F payload /6668 | ffplay -f h261 - (receiver)

which of course means nothing, since I just used libavcodec to encode 
the frames.

Thanks in advance for any feedback you'll be able to give me, I hope to 
hear from you soon.

Regards,
Lorenzo

--
Lorenzo Miniero, Junior Researcher
Dipartimento di Informatica e Sistemistica
Universit�egli Studi di Napoli "Federico II"
Via Claudio 21 -- 80125 Napoli (Italy)
Phone: +390817683821 - Fax: +390817683816
Email: lorenzo miniero unina it