| .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later |
| |
| .. _packed-yuv: |
| |
| ****************** |
| Packed YUV formats |
| ****************** |
| |
| 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. |
| |
| .. note:: |
| |
| - In all the tables that follow, bit 7 is the most significant bit in a byte. |
| - 'Y', 'Cb' and 'Cr' denote bits of the luma, blue chroma (also known as |
| 'U') and red chroma (also known as 'V') components respectively. 'A' |
| denotes bits of the alpha component (if supported by the format), and 'X' |
| denotes padding bits. |
| |
| |
| 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. |
| |
| The next table lists the packed YUV 4:4:4 formats with less than 8 bits per |
| component. They are named based on the order of the Y, Cb and Cr components as |
| seen in a 16-bit word, which is then stored in memory in little endian byte |
| order, and on the number of bits for each component. For instance the YUV565 |
| format stores a pixel in a 16-bit word [15:0] laid out at as [Y'\ :sub:`4-0` |
| Cb\ :sub:`5-0` Cr\ :sub:`4-0`], and stored in memory in two bytes, |
| [Cb\ :sub:`2-0` Cr\ :sub:`4-0`] followed by [Y'\ :sub:`4-0` Cb\ :sub:`5-3`]. |
| |
| .. raw:: latex |
| |
| \begingroup |
| \tiny |
| \setlength{\tabcolsep}{2pt} |
| |
| .. 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}| |
| |
| .. flat-table:: Packed YUV 4:4:4 Image Formats (less than 8bpc) |
| :header-rows: 2 |
| :stub-columns: 0 |
| |
| * - Identifier |
| - Code |
| |
| - :cspan:`7` Byte 0 in memory |
| |
| - :cspan:`7` Byte 1 |
| |
| * - |
| - |
| - 7 |
| - 6 |
| - 5 |
| - 4 |
| - 3 |
| - 2 |
| - 1 |
| - 0 |
| |
| - 7 |
| - 6 |
| - 5 |
| - 4 |
| - 3 |
| - 2 |
| - 1 |
| - 0 |
| |
| * .. _V4L2-PIX-FMT-YUV444: |
| |
| - ``V4L2_PIX_FMT_YUV444`` |
| - 'Y444' |
| |
| - Cb\ :sub:`3` |
| - Cb\ :sub:`2` |
| - Cb\ :sub:`1` |
| - Cb\ :sub:`0` |
| - Cr\ :sub:`3` |
| - Cr\ :sub:`2` |
| - Cr\ :sub:`1` |
| - Cr\ :sub:`0` |
| |
| - a\ :sub:`3` |
| - a\ :sub:`2` |
| - a\ :sub:`1` |
| - a\ :sub:`0` |
| - Y'\ :sub:`3` |
| - Y'\ :sub:`2` |
| - Y'\ :sub:`1` |
| - Y'\ :sub:`0` |
| |
| * .. _V4L2-PIX-FMT-YUV555: |
| |
| - ``V4L2_PIX_FMT_YUV555`` |
| - 'YUVO' |
| |
| - Cb\ :sub:`2` |
| - Cb\ :sub:`1` |
| - Cb\ :sub:`0` |
| - Cr\ :sub:`4` |
| - Cr\ :sub:`3` |
| - Cr\ :sub:`2` |
| - Cr\ :sub:`1` |
| - Cr\ :sub:`0` |
| |
| - a |
| - Y'\ :sub:`4` |
| - Y'\ :sub:`3` |
| - Y'\ :sub:`2` |
| - Y'\ :sub:`1` |
| - Y'\ :sub:`0` |
| - Cb\ :sub:`4` |
| - Cb\ :sub:`3` |
| |
| * .. _V4L2-PIX-FMT-YUV565: |
| |
| - ``V4L2_PIX_FMT_YUV565`` |
| - 'YUVP' |
| |
| - Cb\ :sub:`2` |
| - Cb\ :sub:`1` |
| - Cb\ :sub:`0` |
| - Cr\ :sub:`4` |
| - Cr\ :sub:`3` |
| - Cr\ :sub:`2` |
| - Cr\ :sub:`1` |
| - Cr\ :sub:`0` |
| |
| - Y'\ :sub:`4` |
| - Y'\ :sub:`3` |
| - Y'\ :sub:`2` |
| - Y'\ :sub:`1` |
| - Y'\ :sub:`0` |
| - Cb\ :sub:`5` |
| - Cb\ :sub:`4` |
| - Cb\ :sub:`3` |
| |
| .. raw:: latex |
| |
| \endgroup |
| |
| .. note:: |
| |
| For the YUV444 and YUV555 formats, the value of alpha bits is undefined |
| when reading from the driver, ignored when writing to the driver, except |
| when alpha blending has been negotiated for a :ref:`Video Overlay |
| <overlay>` or :ref:`Video Output Overlay <osd>`. |
| |
| |
| The next table lists the packed YUV 4:4:4 formats with 8 bits per component. |
| They are named based on the order of the Y, Cb and Cr components as stored in |
| memory, and on the total number of bits per pixel. For instance, the VUYX32 |
| format stores a pixel with Cr\ :sub:`7-0` in the first byte, Cb\ :sub:`7-0` in |
| the second byte and Y'\ :sub:`7-0` in the third byte. |
| |
| .. flat-table:: Packed YUV Image Formats (8bpc) |
| :header-rows: 1 |
| :stub-columns: 0 |
| |
| * - Identifier |
| - Code |
| - Byte 0 |
| - Byte 1 |
| - Byte 2 |
| - Byte 3 |
| |
| * .. _V4L2-PIX-FMT-YUV32: |
| |
| - ``V4L2_PIX_FMT_YUV32`` |
| - 'YUV4' |
| |
| - A\ :sub:`7-0` |
| - Y'\ :sub:`7-0` |
| - Cb\ :sub:`7-0` |
| - Cr\ :sub:`7-0` |
| |
| * .. _V4L2-PIX-FMT-AYUV32: |
| |
| - ``V4L2_PIX_FMT_AYUV32`` |
| - 'AYUV' |
| |
| - A\ :sub:`7-0` |
| - Y'\ :sub:`7-0` |
| - Cb\ :sub:`7-0` |
| - Cr\ :sub:`7-0` |
| |
| * .. _V4L2-PIX-FMT-XYUV32: |
| |
| - ``V4L2_PIX_FMT_XYUV32`` |
| - 'XYUV' |
| |
| - X\ :sub:`7-0` |
| - Y'\ :sub:`7-0` |
| - Cb\ :sub:`7-0` |
| - Cr\ :sub:`7-0` |
| |
| * .. _V4L2-PIX-FMT-VUYA32: |
| |
| - ``V4L2_PIX_FMT_VUYA32`` |
| - 'VUYA' |
| |
| - Cr\ :sub:`7-0` |
| - Cb\ :sub:`7-0` |
| - Y'\ :sub:`7-0` |
| - A\ :sub:`7-0` |
| |
| * .. _V4L2-PIX-FMT-VUYX32: |
| |
| - ``V4L2_PIX_FMT_VUYX32`` |
| - 'VUYX' |
| |
| - Cr\ :sub:`7-0` |
| - Cb\ :sub:`7-0` |
| - Y'\ :sub:`7-0` |
| - X\ :sub:`7-0` |
| |
| .. note:: |
| |
| - The alpha component is expected to contain a meaningful value that can be |
| used by drivers and applications. |
| - The padding bits contain undefined 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. |
