On Tue, 27 Jul 2021 at 14:58, Nicolas Dufresne <nicolas@xxxxxxxxxxxx> wrote: > > Le mardi 27 juillet 2021 à 11:20 +0800, Ming Qian a écrit : > > NT8 is 8-bit tiled nv12 format used by amphion decoder. > > NT10 is 10-bit tiled format used by amphion decoder. > > The tile size is 8x128 > > > > Signed-off-by: Ming Qian <ming.qian@xxxxxxx> > > Signed-off-by: Shijie Qin <shijie.qin@xxxxxxx> > > Signed-off-by: Zhou Peng <eagle.zhou@xxxxxxx> > > --- > > .../userspace-api/media/v4l/pixfmt-reserved.rst | 15 +++++++++++++++ > > drivers/media/v4l2-core/v4l2-ioctl.c | 2 ++ > > include/uapi/linux/videodev2.h | 2 ++ > > 3 files changed, 19 insertions(+) > > > > diff --git a/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst b/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst > > index c9231e18859b..2deae49210a7 100644 > > --- a/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst > > +++ b/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst > > @@ -256,3 +256,18 @@ please make a proposal on the linux-media mailing list. > > of tiles, resulting in 32-aligned resolutions for the luminance plane > > and 16-aligned resolutions for the chrominance plane (with 2x2 > > subsampling). > > + * .. _V4L2-PIX-FMT-NT8: > > + > > + - ``V4L2_PIX_FMT_NT8`` > > + - 'NA12' > > + - Two-planar NV12-based format used by the video engine found on Amphion decoder, > > + with 8x128 tiles for the luminance plane and chrominance plane. > > + The number of bytes in one luminance or chrominance row must be divisible by 256. > > + * .. _V4L2-PIX-FMT-NT10: > > There is a large spread of "vendor specific" format that aren't really specific, > or complex enough to be worth being marked as vendor format. As per my reading > of this description, this is linearly layout 8x128 tiled format, with no > compression or anything (well unless you forgot to mention). As a side effect, > we should give that format an explicit name (NT8 is cryptic). What about > V4L2_PIX_FMT_NV12_8L128, my colleague is about to send a proposal in that > direction. That would be NV12 with plane tiled 8x128 bytes and layout linearly, > row by row, left to right. We already have cryptic formats like SUNXI, HM12 that > are literally just that, simple tiling, and we endup having to use obscure > vendor name whenever other HW uses the same. > > (this comment extends to the other formats here) > Here's the proposal Nicolas is talking about: https://lore.kernel.org/linux-media/20210727145745.25203-1-ezequiel@xxxxxxxxxxxxx/T/#t V4L2_PIX_FMT_NV12_8L128 makes sense, please also add support for this format in GStreamer. I think that makes it easier to confirm the layout of the format. Thanks! Ezequiel
