Re: [Linphone-users] linphone & tandberg with H264

[Simon Morlat]

Good to know the lastest plugin solved the problem !
No, linphone never upscales the video before encoding it. The video
resolution of the outgoing stream is controlled by the 'preferred video
size' dropdown list in the property window, in the multimedia tab.
Of course if bandwidth settings are too low, linphone might decide to
choose a lower resolution.
H263 is limited to QCIF, support for this codec is minimalist as it is
obsolete.
Use H263-1998 instead. However with this codec linphone will signal to
the far end to be only able to receive CIF. You can change this setting
by editing coreapi/linphonecore.c and replacing the "CIF=1;QCIF=1"
string by "4CIF=1".
Personnaly for HD (well SVGA currently) I recommend MP4V-ES (mpeg4),
because it is not consuming a lot of CPU, gives a reasonable quality and
is well supported everywhere.
When using H263-1998, support for VGA family sizes is coded as an
extension into the bitstream, which can make sometimes interoperability
problems. Bare H263 specification only supports QCIF,CIF and 4CIF.

Simon

Le mardi 09 février 2010 à 23:37 +0100, Julien Garet a écrit :
> Hello,
> 
> It works quite well using the last version of msx264. But I have a few  
> questions. Linphone sends H264 video to the tandberg and it seems to  
> be 1080p video that is upscaled from source (my webcam isn't HD)  
> consuming unnecessary cpu and bandwidth. Is there a way to limit  
> resolution in the negociation phase ? And for reception, negociation  
> ends to H263 and somerhing like QCIF resolution from the tandberg to  
> linphone, do you know how this happens and can be improved ? The idea  
> is to bring better end user experience when communicating between room  
> equipments and desktop videoconferencing using linphone instead of  
> commercial apps for my users.
> 
> Julien Garet
> 
> Le 9 févr. 2010 à 17:22, Simon Morlat <address@hidden> a  
> écrit :
> 
> > Hi Julien,
> >
> > msx264-1.3.0 has packetization-mode=0 enabled by default since x264  
> > has
> > finally integrated support for slice size limit. So no one should  
> > worry
> > now about packetization-modes with lastest msx264.
> > However it has been discovered recently that msx264-1.3.0 outputs
> > non-baseline H.264, due to internal changes in x264 that I missed.  
> > Many
> > decoders don't support yet non baseline streams, and anyway the  
> > encoder
> > should not deliver non baseline streams by default.
> > Try with that last release of msx264:
> >
> > http://download.savannah.gnu.org/releases-noredirect/linphone/plugins/sources/msx264-1.3.1.tar.gz
> >
> > I hope this will solve your problem.
> >
> > Simon
> >
> >
> > Le mardi 09 février 2010 à 09:31 +0100, Julien Garet a écrit :
> >> Le lundi 08 février 2010 à 17:51 +0100, Julien Garet a écrit :
> >>> Hello,
> >>>
> >>> I am trying to make calls from linphone to tandberg equipments  
> >>> (Tanbderg
> >>> Edge 95, 3000 MXP and Tandberg T1). I can successfuly make calls,  
> >>> I can
> >>> see what comes from the tandberg camera, can hear and be heard by  
> >>> the
> >>> other side but on the tandberg screen nothing appears. Looking to  
> >>> the
> >>> equipment console, video received is noted : H264 address@hidden (it  
> >>> should be
> >>> something like : H264 address@hidden).
> >>> It seems to work well using h263 codecs.
> >>> So, my question is : has anyone already done some testing between  
> >>> room
> >>> codecs (tandberg for instance) with H264 video ? Does linphone  
> >>> support
> >>> HD resolutions ? (such as 720p or 1080p/i)
> >>
> >> As an answer to myself, I've seen in the FAQ that H264 communication
> >> with other isn't supported because packetization-mode value. But, the
> >> most recent versions of msx264 (at least 1.3.0) does not support the
> >> options told in the FAQ (./configure --enable-hacked-x264), so which
> >> version should I use ?
> >>
> >> Julien
> >>
> >>
> >>
> >>
> >> _______________________________________________
> >> Linphone-users mailing list
> >> address@hidden
> >> http://lists.nongnu.org/mailman/listinfo/linphone-users
> >
> >