Protocol for sharing video textures?

[Daniel Stone]

Hi Jean-Michaël,

On 6 July 2017 at 09:07, Jean-Michaël Celerier
<jeanmichael.celerier at gmail.com> wrote:
> In the windows and macOS world, the operating system / graphics driver
> tandem provides a feature that may be irrelevant for most desktop use cases,
> but quite important for artistic creators: zero-copy texture sharing across
> processes.

No, it's very very relevant!

> Do you think that such a feature could be a wayland protocol extension ?
> What "building blocks" are missing to get this to work reliably on Linux ?
> It would greatly simplify and improve the performance of artistic
> applications, such as video mapping, etc...

The low-level mechanism used for sharing these days is called
'dmabuf', which gives you a file descriptor referring to the
underlying buffer. It's supported in GStreamer, VA-API and V4L2 for
media decode/encode operations, by EGL (via
EGL_EXT_image_dma_buf_import and
EGL_EXT_image_dma_buf_import_modifiers), and by Wayland itself via the
zwp_linux_dmabuf_v1 protocol. It's also supported by KMS for direct
display.

Cheers,
Daniel