This way we don't have to repeat over and over how the pixels are packed in NV15. Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx> --- .../media/v4l/pixfmt-yuv-planar.rst | 144 ++++++++++++++++-- 1 file changed, 131 insertions(+), 13 deletions(-) diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst index 1d43532095c07..2f0e0c97870b2 100644 --- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst +++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst @@ -373,25 +373,143 @@ two non-contiguous planes. Tiled NV15 ---------- -``V4L2_PIX_FMT_NV15_4L4`` Semi-planar 10-bit YUV 4:2:0 formats, using 4x4 tiling. -All components are packed without any padding between each other. -As a side-effect, each group of 4 components are stored over 5 bytes -(YYYY or UVUV = 4 * 10 bits = 40 bits = 5 bytes). +Semi-planar 10-bit YUV 4:2:0 formats. All components are packed +without any padding between each other. Each components group occupy 15 +bits and are usually stored in group of 4 components stored over 5 bytes +(YYYY or UVUV = 4 * 10 bits = 40 bits = 5 bytes) or partitioned into +upper 8 bit and lower 2 bits. The final arrangement will vary depending if +the hardware operated in little or big endian. + +.. flat-table:: Little endian sample of 4 NV15 luma pixels + :header-rows: 1 + :stub-columns: 1 + + * - Bit + - 7 + - 6 + - 5 + - 4 + - 3 + - 2 + - 1 + - 0 + * - Byte 0 + - Y'\ :sub:`0:7` + - Y'\ :sub:`0:6` + - Y'\ :sub:`0:5` + - Y'\ :sub:`0:4` + - Y'\ :sub:`0:3` + - Y'\ :sub:`0:2` + - Y'\ :sub:`0:1` + - Y'\ :sub:`0:0` + * - Byte 1 + - Y'\ :sub:`1:5` + - Y'\ :sub:`1:4` + - Y'\ :sub:`1:3` + - Y'\ :sub:`1:2` + - Y'\ :sub:`1:1` + - Y'\ :sub:`1:0` + - Y'\ :sub:`0:9` + - Y'\ :sub:`0:8` + * - Byte 2 + - Y'\ :sub:`2:3` + - Y'\ :sub:`2:2` + - Y'\ :sub:`2:1` + - Y'\ :sub:`2:0` + - Y'\ :sub:`1:9` + - Y'\ :sub:`1:8` + - Y'\ :sub:`1:7` + - Y'\ :sub:`1:6` + * - Byte 3 + - Y'\ :sub:`3:1` + - Y'\ :sub:`3:0` + - Y'\ :sub:`2:9` + - Y'\ :sub:`2:8` + - Y'\ :sub:`2:7` + - Y'\ :sub:`2:6` + - Y'\ :sub:`2:5` + - Y'\ :sub:`2:4` + * - Byte 4 + - Y'\ :sub:`3:9` + - Y'\ :sub:`3:8` + - Y'\ :sub:`3:7` + - Y'\ :sub:`3:6` + - Y'\ :sub:`3:5` + - Y'\ :sub:`3:4` + - Y'\ :sub:`3:3` + - Y'\ :sub:`3:2` + +.. flat-table:: Big endian sample of 4 NV15 luma pixels + :header-rows: 1 + :stub-columns: 1 + + * - Bit + - 7 + - 6 + - 5 + - 4 + - 3 + - 2 + - 1 + - 0 + * - Byte 0 + - Y'\ :sub:`0:9` + - Y'\ :sub:`0:8` + - Y'\ :sub:`0:7` + - Y'\ :sub:`0:6` + - Y'\ :sub:`0:5` + - Y'\ :sub:`0:4` + - Y'\ :sub:`0:3` + - Y'\ :sub:`0:2` + * - Byte 1 + - Y'\ :sub:`0:1` + - Y'\ :sub:`0:0` + - Y'\ :sub:`1:9` + - Y'\ :sub:`1:8` + - Y'\ :sub:`1:7` + - Y'\ :sub:`1:6` + - Y'\ :sub:`1:5` + - Y'\ :sub:`1:4` + * - Byte 2 + - Y'\ :sub:`1:3` + - Y'\ :sub:`1:2` + - Y'\ :sub:`1:1` + - Y'\ :sub:`1:0` + - Y'\ :sub:`2:9` + - Y'\ :sub:`2:8` + - Y'\ :sub:`2:7` + - Y'\ :sub:`2:6` + * - Byte 3 + - Y'\ :sub:`2:5` + - Y'\ :sub:`2:4` + - Y'\ :sub:`2:3` + - Y'\ :sub:`2:2` + - Y'\ :sub:`2:1` + - Y'\ :sub:`2:0` + - Y'\ :sub:`3:9` + - Y'\ :sub:`3:8` + * - Byte 4 + - Y'\ :sub:`3:7` + - Y'\ :sub:`3:6` + - Y'\ :sub:`3:5` + - Y'\ :sub:`3:4` + - Y'\ :sub:`3:3` + - Y'\ :sub:`3:2` + - Y'\ :sub:`3:1` + - Y'\ :sub:`3:0` + +``V4L2_PIX_FMT_NV15_4L4`` stores pixels in 4x4 tiles, and stores tiles linearly +in memory. The tiles contains little endian NV15 data. ``V4L2_PIX_FMT_NV12M_10BE_8L128`` is similar to ``V4L2_PIX_FMT_NV12M`` but stores 10 bits pixels in 2D 8x128 tiles, and stores tiles linearly in memory. the data is arranged in big endian order. + The image height must be aligned to a multiple of 128. The layouts of the luma and chroma planes are identical. -Note the tile size is 8bytes multiplied by 128 bytes, -it means that the low bits and high bits of one pixel may be in different tiles. -The 10 bit pixels are packed, so 5 bytes contain 4 10-bit pixels layout like -this (for luma): -byte 0: Y0(bits 9-2) -byte 1: Y0(bits 1-0) Y1(bits 9-4) -byte 2: Y1(bits 3-0) Y2(bits 9-6) -byte 3: Y2(bits 5-0) Y3(bits 9-8) -byte 4: Y3(bits 7-0) +Note the tile size is 8 bytes multiplied by 128 bytes, +it means that the low bits and high bits of one pixel may +be in different tiles. ``V4L2_PIX_FMT_NV12_10BE_8L128`` is similar to ``V4L2_PIX_FMT_NV12M_10BE_8L128`` but stores two planes in one memory. -- 2.40.1
