Re: [PATCH 1/4] drm/fourcc: Add modifier definitions for describing Amlogic Video Framebuffer Compression

Pekka Paalanen
2020-03-06T16:18:02Z

[-- Attachment #1.1: Type: text/plain, Size: 1367 bytes --]

On Fri, 6 Mar 2020 15:40:01 +0100
Neil Armstrong <narmstrong@baylibre.com> wrote:

> Hi Pekka, Brian, Daniel,
>
> On 06/03/2020 11:13, Daniel Vetter wrote:
> > On Tue, Mar 03, 2020 at 05:33:32PM +0200, Pekka Paalanen wrote:

...

> >> Sorry, it's waypipe, not pipewire:
> >> https://gitlab.freedesktop.org/mstoeckl/waypipe/
> >
> > I do think this is very much something we want to make possible. They
> > might pick a silly modifier (compression modifiers only compress bw, by
> > necessity the lossless ones have to increase storage space so kinda dumb
> > thing to push over the network if you don't add .xz or whatever on top).
>
> The AFBC, and Amlogic FBC are not size optimized compressions, but really
> layout and memory access optimized compressions, without a proper network
> size compression, transferring plain NV12 would be the same.

FWIW, waypipe is not intended to be the most efficient network
streaming protocol, but it is intended to be a direct Wayland protocol
proxy (X11 forwarding, anyone?), which means that it needs to be able to
transmit also dmabuf buffers as is. It does not want to understand
modifiers but just send opaque data.

It may or may not do lossless compression of the data it sends over the
wire, but it will replicate the dmabuf on the remote end.

Or so I'm told.

Thanks,
pq

[-- Attachment #1.2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]