[Spice-devel] RFC - adding vp8 support

[Marc-André Lureau]

Hi

----- Original Message -----
> Hi folks,
> 
> The spice-html5 client supports streaming, for low values of 'support'.

So you mean the streaming for the video regions only, right?

> It would be a fairly substantial boost to it's performance if Spice
> could encode in a format supported by the MediaSource api such as vp8.

In theory, MediaSource is format agnostic iirc.

Isn't mjpeg fast enough to decode? I would assume a browser is good to it :)

> We've talked on an off through the years about adding that support; I'd
> like to go ahead and make that effort.
> 
> It looks like the task will be fairly straight forward.  There are some
> aspects of the spice streaming functionality that are wrapped inside
> mjpeg_encoder.c, and those should logically get broken out.
> 
> It's not clear if we want to continue with the same stream rate logic;
> the libvpx encoder has a built in 'target bit rate' setting that may be
> a more logical approach.
> 
> But my instinct is to add a video_codec.[ch] set to parallel the
> snd_codec.[ch] in spice-common, and then to pare out the truly mpeg only
> parts of the logic into those files.
> 
> Once that was done, I'd introduce a codec type of VP8 and go from there.
> 
> Is there anything else I should consider before I begin?  Have others
> started in on this work?

I would consider gstreamer instead. At some point, I think spice will stream
the whole desktop with a lossless video codec (hopefully supported by the
hardware) and offer an adaptive rtp server for streaming, or even an http based
adaptive streaming (dash). GStreamer truly shines for this work as it
would abstract away the whole encoding & streaming part while optimizing the
use of available hardware.