[FFmpeg-devel] [PATCH v3] fbdetile cpu based detiling of framebuffers v03

[Lynne]

Jun 29, 2020, 18:58 by hanishkvc at gmail.com:

> v03-20200629IST2208 fbdetile
>
> Added a generic detiling logic, which can be easily configured to
> detile many different tiling schemes.
>
> The same is inturn used to detile Intel Tile-Yf layout.
>
> NOTE: This is a full patch, it contains the previous versions also
> in it.
>
> v02-20200627IST2331
>
> Unrolled Intel Legacy Tile-Y detiling logic.
>
> Also a consolidated patch file, instead of the previous development
> flow based multiple patch files.
>
> v01-20200627IST1308
>
> Implemented Intel Legacy Tile-X and Tile-Y detiling logic
>
> NOTES:
>
> This video filter allows framebuffers which are tiled to be detiled
> using logic running on the cpu, into a linear layout.
>
> Currently it supports Intel Legacy Tile-X and Tile-Y layout detiling,
> as well as the newer Intel Tile-Yf layouts.
>
> THis should help one to work with frames captured (say using kmsgrab)
> on laptops having Intel GPU. This can be done live while capturing
> itself, or it can be applied later as a seperate pass.
>
> Tile-X conversion logic has been explicitly cross checked, with Tile-X
> based frames. However Tile-Y and Tile-Yf conv logics havent been tested
> with Tile-Y | Tile-Yf based frames, but it should potentially get the
> job done, based on my current understanding of these layout formats.
>
> TODO1: At a later time have to generate Tile-Y|Yf based frames, and then
> cross check the corresponding logic explicitly.
>
> TODO2: May be use OpenGL or Vulcan buffer helper routines to do the
> layout conversion. But some online discussions from sometime back seem
> to indicate that this path is not fully bug free currently.
>

Still not happening, I'd like to see this done properly with hwdownload. While what you
have works as a hack, we're not interested in hacks but something that works universally.
As I said before, it can be easily sped up by a factor of 4 or 8 using SIMD, so its
unjustifiable to have this in the codebase as a filter.