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diff --git a/Documentation/media/uapi/v4l/planar-apis.rst b/Documentation/media/uapi/v4l/planar-apis.rst deleted file mode 100644 index a422dc9d592c..000000000000 --- a/Documentation/media/uapi/v4l/planar-apis.rst +++ /dev/null @@ -1,68 +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 - -.. _planar-apis: - -***************************** -Single- and multi-planar APIs -***************************** - -Some devices require data for each input or output video frame to be -placed in discontiguous memory buffers. In such cases, one video frame -has to be addressed using more than one memory address, i.e. one pointer -per "plane". A plane is a sub-buffer of the current frame. For examples -of such formats see :ref:`pixfmt`. - -Initially, V4L2 API did not support multi-planar buffers and a set of -extensions has been introduced to handle them. Those extensions -constitute what is being referred to as the "multi-planar API". - -Some of the V4L2 API calls and structures are interpreted differently, -depending on whether single- or multi-planar API is being used. An -application can choose whether to use one or the other by passing a -corresponding buffer type to its ioctl calls. Multi-planar versions of -buffer types are suffixed with an ``_MPLANE`` string. For a list of -available multi-planar buffer types see enum -:c:type:`v4l2_buf_type`. - - -Multi-planar formats -==================== - -Multi-planar API introduces new multi-planar formats. Those formats use -a separate set of FourCC codes. It is important to distinguish between -the multi-planar API and a multi-planar format. Multi-planar API calls -can handle all single-planar formats as well (as long as they are passed -in multi-planar API structures), while the single-planar API cannot -handle multi-planar formats. - - -Calls that distinguish between single and multi-planar APIs -=========================================================== - -:ref:`VIDIOC_QUERYCAP <VIDIOC_QUERYCAP>` - Two additional multi-planar capabilities are added. They can be set - together with non-multi-planar ones for devices that handle both - single- and multi-planar formats. - -:ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>`, :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>`, :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` - New structures for describing multi-planar formats are added: struct - :c:type:`v4l2_pix_format_mplane` and - struct :c:type:`v4l2_plane_pix_format`. - Drivers may define new multi-planar formats, which have distinct - FourCC codes from the existing single-planar ones. - -:ref:`VIDIOC_QBUF <VIDIOC_QBUF>`, :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>`, :ref:`VIDIOC_QUERYBUF <VIDIOC_QUERYBUF>` - A new struct :c:type:`v4l2_plane` structure for - describing planes is added. Arrays of this structure are passed in - the new ``m.planes`` field of struct - :c:type:`v4l2_buffer`. - -:ref:`VIDIOC_REQBUFS <VIDIOC_REQBUFS>` - Will allocate multi-planar buffers as requested. |