On Fri, Apr 15, 2011 at 11:08:01PM +0300, Yaniv Kaul wrote: > On 4/15/2011 18:22, Alon Levy wrote: > >On Thu, Apr 14, 2011 at 03:20:40PM +0200, Andrea Celestino wrote: > >>I would like to improve the streaming video performance in Spice, do you > >>think that is possible to improve it? In what way? > >>Are there documents that describes in detail how spice works with video? > >The best I can offer in terms of documentation is the pdfs in the documents > >section of spice-space.org, I imagine you are looking for something more, > >sorry to disappoint. > > > >The code you are interested in is server/red_worker.c, but that's not very > >helpful since that file is huge. Would be nice to split the video related > >stuff to a separate file. > > > >worker->streaming_video - determines how we handle streaming video > > > >git grep stream -- server/red_worker.c > > > >I can give you better pointers if you ask more specific questions, but doing > >the documentation myself right now.. too much work. > > > >overview of what spice does: > > * determine if a given draw operation (has to be an opaque copy iirc) is > > repeated to the same area. > > * if so, starts a mjpeg encoder and sends the stream to the client > > > >how to improve this (some is on the Features page in spice-space): > > * learn to do various video acceleration apis (windows has it, linux has > > it) > > * this is by far the best way to go regarding performance, unless you are > > willing to sacrifice cpu for bandwidth in which case I guess you would > > reencode. > > * otoh this is a pretty large change to multiple parts of spice: > > * you need to update the driver for each platform you choose to support, > > update the protocol, teach server and client > > * it's definitely on the todo list, but no date set. > > * replace mjpeg with a different encoder > > * if it's just a better performing encoder, clear win. > > * otherwise you get the usual cpu/bw tradeoff. > > * or you could try to learn which encoder fits which stream (based on some > > metric, could be the performance of the encoders themselves) > > * just throwing an idea. > > > >Alon > > Compressed stream pass-through may also be a viable options > sometimes - do not decode on the guest, re-encode in mjpeg and > decode on the client - just pass the compressed stream from the > guest to the client and decode there. > Of course, you need to have the same decoder on the client as you'd > have on the VM, which makes it more fun, but others have been doing > it. That's what video acceleration APIs (vdpau for instance) are all about.
> Y. > > >>2011/4/11 Alon Levy<al...@redhat.com> > >> > >>>On Mon, Apr 11, 2011 at 03:48:08PM +0200, Andrea Celestino wrote: > >>>>Hi, > >>>>I have installed Spice and now I'm trying to use it. I'm interested in > >>>how > >>>>spice manage streaming video. I read that there is the option > >>>> > >>>>-streaming-video=[all|off|filter] > >>>> > >>>>Can you explain me the difference between these three option? > >>>>Which source file read the command line? > >>>>Why I have tried to play a video in a player but i have not notice any > >>>>difference between the two options 'off' and 'filter'? > >>>> > >>>Look at http://cgit.freedesktop.org/spice/spice/tree/server/red_worker.c > >>> > >>>search for STREAM_VIDEO_FILTER > >>> > >>>The switch toggles modes for creating streams: > >>> off - never create > >>> all/filter - create either based on smallest size, or just based on > >>> number of consecutive opaque copies to same area. > >>> > >>>>Thanks very much for the help. > >>>>_______________________________________________ > >>>>Spice-devel mailing list > >>>>Spice-devel@lists.freedesktop.org > >>>>http://lists.freedesktop.org/mailman/listinfo/spice-devel > >>> > >>_______________________________________________ > >>Spice-devel mailing list > >>Spice-devel@lists.freedesktop.org > >>http://lists.freedesktop.org/mailman/listinfo/spice-devel > >_______________________________________________ > >Spice-devel mailing list > >Spice-devel@lists.freedesktop.org > >http://lists.freedesktop.org/mailman/listinfo/spice-devel > > _______________________________________________ > Spice-devel mailing list > Spice-devel@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/spice-devel _______________________________________________ Spice-devel mailing list Spice-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/spice-devel
