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diff --git a/Documentation/media/uapi/v4l/pixfmt-v4l2.rst b/Documentation/media/uapi/v4l/pixfmt-v4l2.rst deleted file mode 100644 index a993b861bf75..000000000000 --- a/Documentation/media/uapi/v4l/pixfmt-v4l2.rst +++ /dev/null @@ -1,171 +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 - -****************************** -Single-planar format structure -****************************** - -.. tabularcolumns:: |p{4.0cm}|p{2.5cm}|p{11.0cm}| - -.. c:type:: v4l2_pix_format - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_pix_format - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u32 - - ``width`` - - Image width in pixels. - * - __u32 - - ``height`` - - Image height in pixels. If ``field`` is one of ``V4L2_FIELD_TOP``, - ``V4L2_FIELD_BOTTOM`` or ``V4L2_FIELD_ALTERNATE`` then height - refers to the number of lines in the field, otherwise it refers to - the number of lines in the frame (which is twice the field height - for interlaced formats). - * - :cspan:`2` Applications set these fields to request an image - size, drivers return the closest possible values. In case of - planar formats the ``width`` and ``height`` applies to the largest - plane. To avoid ambiguities drivers must return values rounded up - to a multiple of the scale factor of any smaller planes. For - example when the image format is YUV 4:2:0, ``width`` and - ``height`` must be multiples of two. - - For compressed formats that contain the resolution information encoded - inside the stream, when fed to a stateful mem2mem decoder, the fields - may be zero to rely on the decoder to detect the right values. For more - details see :ref:`decoder` and format descriptions. - * - __u32 - - ``pixelformat`` - - The pixel format or type of compression, set by the application. - This is a little endian - :ref:`four character code <v4l2-fourcc>`. V4L2 defines standard - RGB formats in :ref:`pixfmt-rgb`, YUV formats in - :ref:`yuv-formats`, and reserved codes in - :ref:`reserved-formats` - * - __u32 - - ``field`` - - Field order, from enum :c:type:`v4l2_field`. - Video images are typically interlaced. Applications can request to - capture or output only the top or bottom field, or both fields - interlaced or sequentially stored in one buffer or alternating in - separate buffers. Drivers return the actual field order selected. - For more details on fields see :ref:`field-order`. - * - __u32 - - ``bytesperline`` - - Distance in bytes between the leftmost pixels in two adjacent - lines. - * - :cspan:`2` - - Both applications and drivers can set this field to request - padding bytes at the end of each line. Drivers however may ignore - the value requested by the application, returning ``width`` times - bytes per pixel or a larger value required by the hardware. That - implies applications can just set this field to zero to get a - reasonable default. - - Video hardware may access padding bytes, therefore they must - reside in accessible memory. Consider cases where padding bytes - after the last line of an image cross a system page boundary. - Input devices may write padding bytes, the value is undefined. - Output devices ignore the contents of padding bytes. - - When the image format is planar the ``bytesperline`` value applies - to the first plane and is divided by the same factor as the - ``width`` field for the other planes. For example the Cb and Cr - planes of a YUV 4:2:0 image have half as many padding bytes - following each line as the Y plane. To avoid ambiguities drivers - must return a ``bytesperline`` value rounded up to a multiple of - the scale factor. - - For compressed formats the ``bytesperline`` value makes no sense. - Applications and drivers must set this to 0 in that case. - * - __u32 - - ``sizeimage`` - - Size in bytes of the buffer to hold a complete image, set by the - driver. Usually this is ``bytesperline`` times ``height``. When - the image consists of variable length compressed data this is the - number of bytes required by the codec to support the worst-case - compression scenario. - - The driver will set the value for uncompressed images. - - Clients are allowed to set the sizeimage field for variable length - compressed data flagged with ``V4L2_FMT_FLAG_COMPRESSED`` at - :ref:`VIDIOC_ENUM_FMT`, but the driver may ignore it and set the - value itself, or it may modify the provided value based on - alignment requirements or minimum/maximum size requirements. - If the client wants to leave this to the driver, then it should - set sizeimage to 0. - * - __u32 - - ``colorspace`` - - Image colorspace, from enum :c:type:`v4l2_colorspace`. - This information supplements the ``pixelformat`` and must be set - by the driver for capture streams and by the application for - output streams, see :ref:`colorspaces`. - * - __u32 - - ``priv`` - - This field indicates whether the remaining fields of the - struct :c:type:`v4l2_pix_format`, also called the - extended fields, are valid. When set to - ``V4L2_PIX_FMT_PRIV_MAGIC``, it indicates that the extended fields - have been correctly initialized. When set to any other value it - indicates that the extended fields contain undefined values. - - Applications that wish to use the pixel format extended fields - must first ensure that the feature is supported by querying the - device for the :ref:`V4L2_CAP_EXT_PIX_FORMAT <querycap>` - capability. If the capability isn't set the pixel format extended - fields are not supported and using the extended fields will lead - to undefined results. - - To use the extended fields, applications must set the ``priv`` - field to ``V4L2_PIX_FMT_PRIV_MAGIC``, initialize all the extended - fields and zero the unused bytes of the - struct :c:type:`v4l2_format` ``raw_data`` field. - - When the ``priv`` field isn't set to ``V4L2_PIX_FMT_PRIV_MAGIC`` - drivers must act as if all the extended fields were set to zero. - On return drivers must set the ``priv`` field to - ``V4L2_PIX_FMT_PRIV_MAGIC`` and all the extended fields to - applicable values. - * - __u32 - - ``flags`` - - Flags set by the application or driver, see :ref:`format-flags`. - * - union { - - (anonymous) - * - __u32 - - ``ycbcr_enc`` - - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`. - This information supplements the ``colorspace`` and must be set by - the driver for capture streams and by the application for output - streams, see :ref:`colorspaces`. - * - __u32 - - ``hsv_enc`` - - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`. - This information supplements the ``colorspace`` and must be set by - the driver for capture streams and by the application for output - streams, see :ref:`colorspaces`. - * - } - - - * - __u32 - - ``quantization`` - - Quantization range, from enum :c:type:`v4l2_quantization`. - This information supplements the ``colorspace`` and must be set by - the driver for capture streams and by the application for output - streams, see :ref:`colorspaces`. - * - __u32 - - ``xfer_func`` - - Transfer function, from enum :c:type:`v4l2_xfer_func`. - This information supplements the ``colorspace`` and must be set by - the driver for capture streams and by the application for output - streams, see :ref:`colorspaces`. |