| Message ID | 20250423-media-rpi-hevc-dec-v3-1-8fd3fad1d6fb@raspberrypi.com |
|---|---|
| State | New |
| Headers | show |
| Series | Raspberry Pi HEVC decoder driver | expand |
Le mercredi 23 avril 2025 à 18:20 +0100, Dave Stevenson a écrit : > The Raspberry Pi HEVC decoder uses a tiled format based on > columns for 8 and 10 bit YUV images, so document them as > NV12MT_COL128 and NV12MT_10_COL128. > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com> > --- > .../userspace-api/media/v4l/pixfmt-yuv-planar.rst | 42 ++++++++++++++++++++++ > 1 file changed, 42 insertions(+) > > diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst b/Documentation/userspace- > api/media/v4l/pixfmt-yuv-planar.rst > index b788f6933855..b5b590f234b0 100644 > --- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst > +++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst > @@ -827,6 +827,48 @@ Data in the 12 high bits, zeros in the 4 low bits, arranged in little endian ord > - Cb\ :sub:`11` > - Cr\ :sub:`11` > > +V4L2_PIX_FMT_NV12MT_COL128 and V4L2_PIX_FMT_NV12MT_10_COL128 > +------------------------------------------------------------ > + > +``V4L2_PIX_FMT_NV12MT_COL128`` is a tiled version of > +``V4L2_PIX_FMT_NV12M`` where the two planes are split into 128 byte wide columns > +of Y or interleaved CbCr. > + > +V4L2_PIX_FMT_NV12MT_10_COL128 expands that as a 10 bit format where 3 10 bit > +values are packed into a 32bit word. A 128 byte wide column therefore holds 96 > +samples (either Y or interleaved CrCb). That effectively makes it 6 values in a > +64 bit word for the CbCr plane, as the values always go in pairs. Could be nice to mention that this has a verticalement alignment of 8, allowing to represent it as a 128x8 tiled format with a column layout. This was handy for the GStreamer integration your showed me. Nicolas > + > +Bit-packed representation. > + > +.. tabularcolumns:: |p{1.2cm}||p{1.2cm}||p{1.2cm}||p{1.2cm}|p{3.2cm}|p{3.2cm}| > + > +.. flat-table:: > + :header-rows: 0 > + :stub-columns: 0 > + :widths: 8 8 8 8 > + > + * - Y'\ :sub:`00[7:0]` > + - Y'\ :sub:`01[5:0] (bits 7--2)` Y'\ :sub:`00[9:8]`\ (bits 1--0) > + - Y'\ :sub:`02[3:0] (bits 7--4)` Y'\ :sub:`01[9:6]`\ (bits 3--0) > + - unused (bits 7--6)` Y'\ :sub:`02[9:4]`\ (bits 5--0) > + > +.. tabularcolumns:: |p{1.2cm}||p{1.2cm}||p{1.2cm}||p{1.2cm}|p{3.2cm}|p{3.2cm}| > + > +.. flat-table:: > + :header-rows: 0 > + :stub-columns: 0 > + :widths: 12 12 12 12 12 12 12 12 > + > + * - Cb\ :sub:`00[7:0]` > + - Cr\ :sub:`00[5:0]`\ (bits 7--2) Cb\ :sub:`00[9:8]`\ (bits 1--0) > + - Cb\ :sub:`01[3:0]`\ (bits 7--4) Cr\ :sub:`00[9:6]`\ (bits 3--0) > + - unused (bits 7--6) Cb\ :sub:`02[9:4]`\ (bits 5--0) > + - Cr\ :sub:`01[7:0]` > + - Cb\ :sub:`02[5:0]`\ (bits 7--2) Cr\ :sub:`01[9:8]`\ (bits 1--0) > + - Cr\ :sub:`02[3:0]`\ (bits 7--4) Cb\ :sub:`02[9:6]`\ (bits 3--0) > + - unused (bits 7--6) Cr\ :sub:`02[9:4]`\ (bits 5--0) > + > > Fully Planar YUV Formats > ========================
diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst index b788f6933855..b5b590f234b0 100644 --- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst +++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst @@ -827,6 +827,48 @@ Data in the 12 high bits, zeros in the 4 low bits, arranged in little endian ord - Cb\ :sub:`11` - Cr\ :sub:`11` +V4L2_PIX_FMT_NV12MT_COL128 and V4L2_PIX_FMT_NV12MT_10_COL128 +------------------------------------------------------------ + +``V4L2_PIX_FMT_NV12MT_COL128`` is a tiled version of +``V4L2_PIX_FMT_NV12M`` where the two planes are split into 128 byte wide columns +of Y or interleaved CbCr. + +V4L2_PIX_FMT_NV12MT_10_COL128 expands that as a 10 bit format where 3 10 bit +values are packed into a 32bit word. A 128 byte wide column therefore holds 96 +samples (either Y or interleaved CrCb). That effectively makes it 6 values in a +64 bit word for the CbCr plane, as the values always go in pairs. + +Bit-packed representation. + +.. tabularcolumns:: |p{1.2cm}||p{1.2cm}||p{1.2cm}||p{1.2cm}|p{3.2cm}|p{3.2cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 8 8 8 8 + + * - Y'\ :sub:`00[7:0]` + - Y'\ :sub:`01[5:0] (bits 7--2)` Y'\ :sub:`00[9:8]`\ (bits 1--0) + - Y'\ :sub:`02[3:0] (bits 7--4)` Y'\ :sub:`01[9:6]`\ (bits 3--0) + - unused (bits 7--6)` Y'\ :sub:`02[9:4]`\ (bits 5--0) + +.. tabularcolumns:: |p{1.2cm}||p{1.2cm}||p{1.2cm}||p{1.2cm}|p{3.2cm}|p{3.2cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 12 12 12 12 12 12 12 12 + + * - Cb\ :sub:`00[7:0]` + - Cr\ :sub:`00[5:0]`\ (bits 7--2) Cb\ :sub:`00[9:8]`\ (bits 1--0) + - Cb\ :sub:`01[3:0]`\ (bits 7--4) Cr\ :sub:`00[9:6]`\ (bits 3--0) + - unused (bits 7--6) Cb\ :sub:`02[9:4]`\ (bits 5--0) + - Cr\ :sub:`01[7:0]` + - Cb\ :sub:`02[5:0]`\ (bits 7--2) Cr\ :sub:`01[9:8]`\ (bits 1--0) + - Cr\ :sub:`02[3:0]`\ (bits 7--4) Cb\ :sub:`02[9:6]`\ (bits 3--0) + - unused (bits 7--6) Cr\ :sub:`02[9:4]`\ (bits 5--0) + Fully Planar YUV Formats ========================
The Raspberry Pi HEVC decoder uses a tiled format based on columns for 8 and 10 bit YUV images, so document them as NV12MT_COL128 and NV12MT_10_COL128. Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com> --- .../userspace-api/media/v4l/pixfmt-yuv-planar.rst | 42 ++++++++++++++++++++++ 1 file changed, 42 insertions(+)