Hi Gerd, On Mittwoch, 20. November 2019 12:29:29 CET Gerd Hoffmann wrote: > Hi, > > > > > > 3. No support for getting plane requirements from the device (sg vs > > > > > contig, > > > > > size, stride alignment, plane count). > > > > > > > > There is actually a bigger difference that results in that. Vdec > > > > assumes host-allocated buffers coming from a different device, e.g. > > > > virtio-gpu and the host having the right knowledge to allocate the > > > > buffers correctly. This is related to the fact that it's generally > > > > difficult to convey all the allocation constraints in a generic > > > > manner. > > > > > > Yep, buffer handling is tricky, especially when it comes to decoding > > > directly to gpu buffers and also when supporting playback of > > > drm-protected streams where the guest might not be allowed to access > > > the stream data. > > > > Also, if we decide to have a buffer sharing device as Gerd suggested > > in a different thread, > > we'll get less overlaps between video codec feature and camera feature. > > e.g. VIRTIO_VIDEO_T_RESOURCE_* would be simplified. (or removed?) > > Disclaimer: Havn't found the time yet to go over both virtio-video and > virtio-vdec in detail. > > > As Tomasz said, I think virtio-vdec can be modified to support > > encoding as well without big changes. I'm happy to update our > > protocol and driver implementation to support encoding if needed. > > I think it makes sense to have a rough plan first ;) > Is there a virtio-video implementation too? Yes, of course. We will be ready to share the code very soon. Regards, Dmitry. > > When it comes to buffer handling: I don't like that virtio-vdec depends > on virtio-gpu for buffer handling. Allowing sharing buffers between > virtio-vdec and virtio-gpu (and possibly other devices) makes sense as > an optional extension. But IMO the encoder/decoder device should be > able to operate as stand-alone device. > > cheers, > Gerd > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: virtio-dev-unsubscribe@xxxxxxxxxxxxxxxxxxxx > For additional commands, e-mail: virtio-dev-help@xxxxxxxxxxxxxxxxxxxx
