Le vendredi 27 janvier 2023 à 15:34 +0000, John Cox a écrit : > Add documentation for for the Broadcom sand formats to pixfmt-yuv-planar. Not a review comment, but does SAND stand for anything you can share ? > > Signed-off-by: John Cox <jc@xxxxxxxxxxxxx> > --- > .../media/v4l/pixfmt-yuv-planar.rst | 192 ++++++++++++++++++ > 1 file changed, 192 insertions(+) > > diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst > index f1d5bb7b806d..c1dd0856f497 100644 > --- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst > +++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst > @@ -123,6 +123,20 @@ All components are stored with the same number of bits per component. > - Cb, Cr > - Yes > - 4x4 tiles > + * - V4L2_PIX_FMT_NV12_C128 > + - 'CN12' > + - 8 > + - 4:2:0 > + - Cb, Cr > + - Yes > + - 128 byte columns > + * - V4L2_PIX_FMT_P030_C128 > + - 'CN30' > + - 10 > + - 4:2:0 > + - Cb, Cr > + - Yes > + - 128 byte columns > * - V4L2_PIX_FMT_NV16 > - 'NV16' > - 8 > @@ -277,6 +291,8 @@ of the luma plane. > .. _V4L2-PIX-FMT-NV12M-10BE-8L128: > .. _V4L2-PIX-FMT-NV12-10BE-8L128: > .. _V4L2-PIX-FMT-MM21: > +.. _V4L2-PIX-FMT-NV12-C128: > +.. _V4L2-PIX-FMT-P030-C128: > > Tiled NV12 > ---------- > @@ -364,6 +380,182 @@ two non-contiguous planes. > > Example V4L2_PIX_FMT_NV12MT memory layout of tiles > > +``V4L2_PIX_FMT_NV21_C128`` store 8 bit luma and chroma data in 128 byte I think you meant V4L2_PIX_FMT_NV12_C128 ? > +columns. Chroma data follows luma in each column. Height, which must be > +a multiple of 2 (h in the table below) determines the offset to the start > +of chroma data. Overall (luma + chroma) > +column height (ch in the table below) is also required and this is obtained > +by dividing the sizeimage by bytesperline. bytesperline is width rounded up > +to the next multiple of the column width (128). Assuming I understood the description, unlike any other tiled formats, the Y and UV columns are not being split in two plane, but instead Y and UV columns are being interleaved. Am I understanding correctly ? I think the text could be improved in this regard. Note, I totally agree on using NV12 as reference, I see lower that CbCr is effectively interleaved. > + > +.. flat-table:: > + :header-rows: 0 > + :stub-columns: 0 > + :widths: 15 10 10 10 10 4 10 10 10 10 > + > + * - start + 0: > + - Y'\ :sub:`0,0` > + - Y'\ :sub:`0,1` > + - Y'\ :sub:`0,2` > + - Y'\ :sub:`0,3` > + - ... > + - Y'\ :sub:`0,124` > + - Y'\ :sub:`0,125` > + - Y'\ :sub:`0,126` > + - Y'\ :sub:`0,127` > + * - start + 128: > + - Y'\ :sub:`1,0` > + - Y'\ :sub:`1,1` > + - Y'\ :sub:`1,2` > + - Y'\ :sub:`1,3` > + - ... > + - Y'\ :sub:`1,124` > + - Y'\ :sub:`1,125` > + - Y'\ :sub:`1,126` > + - Y'\ :sub:`1,127` > + * - start + 256: > + - Y'\ :sub:`2,0` > + - Y'\ :sub:`2,1` > + - Y'\ :sub:`2,2` > + - Y'\ :sub:`2,3` > + - ... > + - Y'\ :sub:`2,124` > + - Y'\ :sub:`2,125` > + - Y'\ :sub:`2,126` > + - Y'\ :sub:`2,127` > + * - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + * - start + ((h-1) * 128): > + - Y'\ :sub:`h-1,0` > + - Y'\ :sub:`h-1,1` > + - Y'\ :sub:`h-1,2` > + - Y'\ :sub:`h-1,3` > + - ... > + - Y'\ :sub:`h-1,124` > + - Y'\ :sub:`h-1,125` > + - Y'\ :sub:`h-1,126` > + - Y'\ :sub:`h-1,127` > + * - start + ((h) * 128): > + - Cb\ :sub:`0,0` > + - Cr\ :sub:`0,0` > + - Cb\ :sub:`0,1` > + - Cr\ :sub:`0,1` > + - ... > + - Cb\ :sub:`0,62` > + - Cr\ :sub:`0,62` > + - Cb\ :sub:`0,63` > + - Cr\ :sub:`0,63` > + * - start + ((h+1) * 128): > + - Cb\ :sub:`1,0` > + - Cr\ :sub:`1,0` > + - Cb\ :sub:`1,1` > + - Cr\ :sub:`1,1` > + - ... > + - Cb\ :sub:`1,62` > + - Cr\ :sub:`1,62` > + - Cb\ :sub:`1,63` > + - Cr\ :sub:`1,63` > + * - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + * - start + ((h+(h/2)-1) * 128): > + - Cb\ :sub:`(h/2)-1,0` > + - Cr\ :sub:`(h/2)-1,0` > + - Cb\ :sub:`(h/2)-1,1` > + - Cr\ :sub:`(h/2)-1,1` > + - ... > + - Cb\ :sub:`(h/2)-1,62` > + - Cr\ :sub:`(h/2)-1,62` > + - Cb\ :sub:`(h/2)-1,63` > + - Cr\ :sub:`(h/2)-1,63` > + * - start + (ch * 128): > + - Y'\ :sub:`0,128` > + - Y'\ :sub:`0,129` > + - Y'\ :sub:`0,130` > + - Y'\ :sub:`0,131` > + - ... > + - Y'\ :sub:`0,252` > + - Y'\ :sub:`0,253` > + - Y'\ :sub:`0,254` > + - Y'\ :sub:`0,255` > + * - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + - ... > + > +``V4L2_PIX_FMT_P030_C128`` uses the same 128 byte column structure as > +``V4L2_PIX_FMT_NV12_C128``, but encodes 10-bit YUV. > +3 10-bit values are packed into 4 bytes as bits 9:0, 19:10, and 29:20, with > +bits 30 & 31 unused. For the luma plane, bits 9:0 are Y0, 19:10 are Y1, and > +29:20 are Y2. For the chroma plane the samples always come in pairs of Cr > +and Cb, so it needs to be considered 6 values packed in 8 bytes. bytesperline > +is ((width + 95)/96)*128 Maybe insert a phrase related to the use of the same columns pattern as NV12_C128 ? Then from there, its easier to understand why this bytesperline formula. I'm guessing that 96 is the number of pixels that fits 1 row of 128 bytes (128 / 4 * 3). I could not guess why you need 128 times that size though ? Maybe I'm missing something ? > + > +Bit-packed representation - Luma: > + > +.. flat-table:: > + :header-rows: 1 > + :stub-columns: 0 > + > + * - byte > + - value(s) > + * - 0 > + - Y'\ :sub:`00[7:0]` > + * - 1 > + - Y'\ :sub:`01[5:0]`\ (bits 7--2) > + - Y'\ :sub:`00[9:8]`\ (bits 1--0) > + * - 2 > + - Y'\ :sub:`02[3:0]`\ (bits 7--4) > + - Y'\ :sub:`01[9:6]`\ (bits 3--0) > + * - 3 > + - unused (bits 7--6) > + - Y'\ :sub:`02[9:4]`\ (bits 5--0) > + > +Bit-packed representation - Chroma: > + > +.. flat-table:: > + :header-rows: 1 > + :stub-columns: 0 > + > + * - byte > + - value(s) > + * - 0 > + - Cb\ :sub:`00[7:0]` > + * - 1 > + - Cr\ :sub:`00[5:0]`\ (bits 7--2) > + - Cb\ :sub:`00[9:8]`\ (bits 1--0) > + * - 2 > + - Cb\ :sub:`01[3:0]`\ (bits 7--4) > + - Cr\ :sub:`00[9:6]`\ (bits 3--0) > + * - 3 > + - unused (bits 7--6) > + - Cb\ :sub:`02[9:4]`\ (bits 5--0) > + * - 4 > + - Cr\ :sub:`01[7:0]` > + * - 5 > + - Cb\ :sub:`02[5:0]`\ (bits 7--2) > + - Cr\ :sub:`01[9:8]`\ (bits 1--0) > + * - 6 > + - Cr\ :sub:`02[3:0]`\ (bits 7--4) > + - Cb\ :sub:`02[9:6]`\ (bits 3--0) > + * - 7 > + - unused (bits 7--6) > + - Cr\ :sub:`02[9:4]`\ (bits 5--0) > > .. _V4L2-PIX-FMT-NV16: > .. _V4L2-PIX-FMT-NV61:
