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diff --git a/Documentation/media/uapi/v4l/colorspaces-defs.rst b/Documentation/media/uapi/v4l/colorspaces-defs.rst deleted file mode 100644 index e122bbe3d799..000000000000 --- a/Documentation/media/uapi/v4l/colorspaces-defs.rst +++ /dev/null @@ -1,183 +0,0 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections - -**************************** -Defining Colorspaces in V4L2 -**************************** - -In V4L2 colorspaces are defined by four values. The first is the -colorspace identifier (enum :c:type:`v4l2_colorspace`) -which defines the chromaticities, the default transfer function, the -default Y'CbCr encoding and the default quantization method. The second -is the transfer function identifier (enum -:c:type:`v4l2_xfer_func`) to specify non-standard -transfer functions. The third is the Y'CbCr encoding identifier (enum -:c:type:`v4l2_ycbcr_encoding`) to specify -non-standard Y'CbCr encodings and the fourth is the quantization -identifier (enum :c:type:`v4l2_quantization`) to -specify non-standard quantization methods. Most of the time only the -colorspace field of struct :c:type:`v4l2_pix_format` -or struct :c:type:`v4l2_pix_format_mplane` -needs to be filled in. - -.. _hsv-colorspace: - -On :ref:`HSV formats <hsv-formats>` the *Hue* is defined as the angle on -the cylindrical color representation. Usually this angle is measured in -degrees, i.e. 0-360. When we map this angle value into 8 bits, there are -two basic ways to do it: Divide the angular value by 2 (0-179), or use the -whole range, 0-255, dividing the angular value by 1.41. The enum -:c:type:`v4l2_hsv_encoding` specifies which encoding is used. - -.. note:: The default R'G'B' quantization is full range for all - colorspaces except for BT.2020 which uses limited range R'G'B' - quantization. - -.. tabularcolumns:: |p{6.7cm}|p{10.8cm}| - -.. c:type:: v4l2_colorspace - -.. flat-table:: V4L2 Colorspaces - :header-rows: 1 - :stub-columns: 0 - - * - Identifier - - Details - * - ``V4L2_COLORSPACE_DEFAULT`` - - The default colorspace. This can be used by applications to let - the driver fill in the colorspace. - * - ``V4L2_COLORSPACE_SMPTE170M`` - - See :ref:`col-smpte-170m`. - * - ``V4L2_COLORSPACE_REC709`` - - See :ref:`col-rec709`. - * - ``V4L2_COLORSPACE_SRGB`` - - See :ref:`col-srgb`. - * - ``V4L2_COLORSPACE_OPRGB`` - - See :ref:`col-oprgb`. - * - ``V4L2_COLORSPACE_BT2020`` - - See :ref:`col-bt2020`. - * - ``V4L2_COLORSPACE_DCI_P3`` - - See :ref:`col-dcip3`. - * - ``V4L2_COLORSPACE_SMPTE240M`` - - See :ref:`col-smpte-240m`. - * - ``V4L2_COLORSPACE_470_SYSTEM_M`` - - See :ref:`col-sysm`. - * - ``V4L2_COLORSPACE_470_SYSTEM_BG`` - - See :ref:`col-sysbg`. - * - ``V4L2_COLORSPACE_JPEG`` - - See :ref:`col-jpeg`. - * - ``V4L2_COLORSPACE_RAW`` - - The raw colorspace. This is used for raw image capture where the - image is minimally processed and is using the internal colorspace - of the device. The software that processes an image using this - 'colorspace' will have to know the internals of the capture - device. - - - -.. c:type:: v4l2_xfer_func - -.. tabularcolumns:: |p{5.5cm}|p{12.0cm}| - -.. flat-table:: V4L2 Transfer Function - :header-rows: 1 - :stub-columns: 0 - - * - Identifier - - Details - * - ``V4L2_XFER_FUNC_DEFAULT`` - - Use the default transfer function as defined by the colorspace. - * - ``V4L2_XFER_FUNC_709`` - - Use the Rec. 709 transfer function. - * - ``V4L2_XFER_FUNC_SRGB`` - - Use the sRGB transfer function. - * - ``V4L2_XFER_FUNC_OPRGB`` - - Use the opRGB transfer function. - * - ``V4L2_XFER_FUNC_SMPTE240M`` - - Use the SMPTE 240M transfer function. - * - ``V4L2_XFER_FUNC_NONE`` - - Do not use a transfer function (i.e. use linear RGB values). - * - ``V4L2_XFER_FUNC_DCI_P3`` - - Use the DCI-P3 transfer function. - * - ``V4L2_XFER_FUNC_SMPTE2084`` - - Use the SMPTE 2084 transfer function. See :ref:`xf-smpte-2084`. - - - -.. c:type:: v4l2_ycbcr_encoding - -.. tabularcolumns:: |p{7.2cm}|p{10.3cm}| - -.. flat-table:: V4L2 Y'CbCr Encodings - :header-rows: 1 - :stub-columns: 0 - - * - Identifier - - Details - * - ``V4L2_YCBCR_ENC_DEFAULT`` - - Use the default Y'CbCr encoding as defined by the colorspace. - * - ``V4L2_YCBCR_ENC_601`` - - Use the BT.601 Y'CbCr encoding. - * - ``V4L2_YCBCR_ENC_709`` - - Use the Rec. 709 Y'CbCr encoding. - * - ``V4L2_YCBCR_ENC_XV601`` - - Use the extended gamut xvYCC BT.601 encoding. - * - ``V4L2_YCBCR_ENC_XV709`` - - Use the extended gamut xvYCC Rec. 709 encoding. - * - ``V4L2_YCBCR_ENC_BT2020`` - - Use the default non-constant luminance BT.2020 Y'CbCr encoding. - * - ``V4L2_YCBCR_ENC_BT2020_CONST_LUM`` - - Use the constant luminance BT.2020 Yc'CbcCrc encoding. - * - ``V4L2_YCBCR_ENC_SMPTE_240M`` - - Use the SMPTE 240M Y'CbCr encoding. - - - -.. c:type:: v4l2_hsv_encoding - -.. tabularcolumns:: |p{6.5cm}|p{11.0cm}| - -.. flat-table:: V4L2 HSV Encodings - :header-rows: 1 - :stub-columns: 0 - - * - Identifier - - Details - * - ``V4L2_HSV_ENC_180`` - - For the Hue, each LSB is two degrees. - * - ``V4L2_HSV_ENC_256`` - - For the Hue, the 360 degrees are mapped into 8 bits, i.e. each - LSB is roughly 1.41 degrees. - - - -.. c:type:: v4l2_quantization - -.. tabularcolumns:: |p{6.5cm}|p{11.0cm}| - -.. flat-table:: V4L2 Quantization Methods - :header-rows: 1 - :stub-columns: 0 - - * - Identifier - - Details - * - ``V4L2_QUANTIZATION_DEFAULT`` - - Use the default quantization encoding as defined by the - colorspace. This is always full range for R'G'B' (except for the - BT.2020 colorspace) and HSV. It is usually limited range for Y'CbCr. - * - ``V4L2_QUANTIZATION_FULL_RANGE`` - - Use the full range quantization encoding. I.e. the range [0…1] is - mapped to [0…255] (with possible clipping to [1…254] to avoid the - 0x00 and 0xff values). Cb and Cr are mapped from [-0.5…0.5] to - [0…255] (with possible clipping to [1…254] to avoid the 0x00 and - 0xff values). - * - ``V4L2_QUANTIZATION_LIM_RANGE`` - - Use the limited range quantization encoding. I.e. the range [0…1] - is mapped to [16…235]. Cb and Cr are mapped from [-0.5…0.5] to - [16…240]. |