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Diffstat (limited to 'Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst')
| -rw-r--r-- | Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst | 147 |
1 files changed, 140 insertions, 7 deletions
diff --git a/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst b/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst index 84262208dd1c..8ed1a6aff3a6 100644 --- a/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst +++ b/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst @@ -6,12 +6,16 @@ Packed YUV formats ****************** -Description -=========== +Similarly to the packed RGB formats, the packed YUV formats store the Y, Cb and +Cr components consecutively in memory. They may apply subsampling to the chroma +components and thus differ in how they interlave the three components. -Similar to the packed RGB formats these formats store the Y, Cb and Cr -component of each pixel in one 16 or 32 bit word. +4:4:4 Subsampling +================= + +These formats do not subsample the chroma components and store each pixels as a +full triplet of Y, Cb and Cr values. .. raw:: latex @@ -19,11 +23,9 @@ component of each pixel in one 16 or 32 bit word. \tiny \setlength{\tabcolsep}{2pt} -.. _packed-yuv-formats: - .. tabularcolumns:: |p{2.5cm}|p{0.69cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}|p{0.31cm}| -.. flat-table:: Packed YUV Image Formats +.. flat-table:: Packed YUV 4:4:4 Image Formats :header-rows: 2 :stub-columns: 0 @@ -371,3 +373,134 @@ component of each pixel in one 16 or 32 bit word. expected to contain a meaningful value that can be used by drivers and applications. And, the formats XYUV32 and VUYX32 contain undefined alpha values that must be ignored by all applications and drivers. + + +4:2:2 Subsampling +================= + +These formats, commonly referred to as YUYV or YUY2, subsample the chroma +components horizontally by 2, storing 2 pixels in 4 bytes. + +.. flat-table:: Packed YUV 4:2:2 Formats + :header-rows: 1 + :stub-columns: 0 + + * - Identifier + - Code + - Byte 0 + - Byte 1 + - Byte 2 + - Byte 3 + - Byte 4 + - Byte 5 + - Byte 6 + - Byte 7 + * .. _V4L2-PIX-FMT-UYVY: + + - ``V4L2_PIX_FMT_UYVY`` + - 'UYVY' + + - Cb\ :sub:`0` + - Y'\ :sub:`0` + - Cr\ :sub:`0` + - Y'\ :sub:`1` + - Cb\ :sub:`2` + - Y'\ :sub:`2` + - Cr\ :sub:`2` + - Y'\ :sub:`3` + * .. _V4L2-PIX-FMT-VYUY: + + - ``V4L2_PIX_FMT_VYUY`` + - 'VYUY' + + - Cr\ :sub:`0` + - Y'\ :sub:`0` + - Cb\ :sub:`0` + - Y'\ :sub:`1` + - Cr\ :sub:`2` + - Y'\ :sub:`2` + - Cb\ :sub:`2` + - Y'\ :sub:`3` + * .. _V4L2-PIX-FMT-YUYV: + + - ``V4L2_PIX_FMT_YUYV`` + - 'YUYV' + + - Y'\ :sub:`0` + - Cb\ :sub:`0` + - Y'\ :sub:`1` + - Cr\ :sub:`0` + - Y'\ :sub:`2` + - Cb\ :sub:`2` + - Y'\ :sub:`3` + - Cr\ :sub:`2` + * .. _V4L2-PIX-FMT-YVYU: + + - ``V4L2_PIX_FMT_YVYU`` + - 'YVYU' + + - Y'\ :sub:`0` + - Cr\ :sub:`0` + - Y'\ :sub:`1` + - Cb\ :sub:`0` + - Y'\ :sub:`2` + - Cr\ :sub:`2` + - Y'\ :sub:`3` + - Cb\ :sub:`2` + +**Color Sample Location:** +Chroma samples are :ref:`interstitially sited<yuv-chroma-centered>` +horizontally. + + +4:1:1 Subsampling +================= + +This format subsamples the chroma components horizontally by 4, storing 8 +pixels in 12 bytes. + +.. flat-table:: Packed YUV 4:1:1 Formats + :header-rows: 1 + :stub-columns: 0 + + * - Identifier + - Code + - Byte 0 + - Byte 1 + - Byte 2 + - Byte 3 + - Byte 4 + - Byte 5 + - Byte 6 + - Byte 7 + - Byte 8 + - Byte 9 + - Byte 10 + - Byte 11 + * .. _V4L2-PIX-FMT-Y41P: + + - ``V4L2_PIX_FMT_Y41P`` + - 'Y41P' + + - Cb\ :sub:`0` + - Y'\ :sub:`0` + - Cr\ :sub:`0` + - Y'\ :sub:`1` + - Cb\ :sub:`4` + - Y'\ :sub:`2` + - Cr\ :sub:`4` + - Y'\ :sub:`3` + - Y'\ :sub:`4` + - Y'\ :sub:`5` + - Y'\ :sub:`6` + - Y'\ :sub:`7` + +.. note:: + + Do not confuse ``V4L2_PIX_FMT_Y41P`` with + :ref:`V4L2_PIX_FMT_YUV411P <V4L2-PIX-FMT-YUV411P>`. Y41P is derived from + "YUV 4:1:1 *packed*", while YUV411P stands for "YUV 4:1:1 *planar*". + +**Color Sample Location:** +Chroma samples are :ref:`interstitially sited<yuv-chroma-centered>` +horizontally. |