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diff --git a/Documentation/media/uapi/v4l/vidioc-g-enc-index.rst b/Documentation/media/uapi/v4l/vidioc-g-enc-index.rst deleted file mode 100644 index e285a1f14cdf..000000000000 --- a/Documentation/media/uapi/v4l/vidioc-g-enc-index.rst +++ /dev/null @@ -1,156 +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 - -.. _VIDIOC_G_ENC_INDEX: - -************************ -ioctl VIDIOC_G_ENC_INDEX -************************ - -Name -==== - -VIDIOC_G_ENC_INDEX - Get meta data about a compressed video stream - - -Synopsis -======== - -.. c:function:: int ioctl( int fd, VIDIOC_G_ENC_INDEX, struct v4l2_enc_idx *argp ) - :name: VIDIOC_G_ENC_INDEX - - -Arguments -========= - -``fd`` - File descriptor returned by :ref:`open() <func-open>`. - -``argp`` - Pointer to struct :c:type:`v4l2_enc_idx`. - - -Description -=========== - -The :ref:`VIDIOC_G_ENC_INDEX <VIDIOC_G_ENC_INDEX>` ioctl provides meta data about a compressed -video stream the same or another application currently reads from the -driver, which is useful for random access into the stream without -decoding it. - -To read the data applications must call :ref:`VIDIOC_G_ENC_INDEX <VIDIOC_G_ENC_INDEX>` with a -pointer to a struct :c:type:`v4l2_enc_idx`. On success -the driver fills the ``entry`` array, stores the number of elements -written in the ``entries`` field, and initializes the ``entries_cap`` -field. - -Each element of the ``entry`` array contains meta data about one -picture. A :ref:`VIDIOC_G_ENC_INDEX <VIDIOC_G_ENC_INDEX>` call reads up to -``V4L2_ENC_IDX_ENTRIES`` entries from a driver buffer, which can hold up -to ``entries_cap`` entries. This number can be lower or higher than -``V4L2_ENC_IDX_ENTRIES``, but not zero. When the application fails to -read the meta data in time the oldest entries will be lost. When the -buffer is empty or no capturing/encoding is in progress, ``entries`` -will be zero. - -Currently this ioctl is only defined for MPEG-2 program streams and -video elementary streams. - - -.. tabularcolumns:: |p{3.8cm}|p{5.6cm}|p{8.1cm}| - -.. c:type:: v4l2_enc_idx - -.. flat-table:: struct v4l2_enc_idx - :header-rows: 0 - :stub-columns: 0 - :widths: 1 3 8 - - * - __u32 - - ``entries`` - - The number of entries the driver stored in the ``entry`` array. - * - __u32 - - ``entries_cap`` - - The number of entries the driver can buffer. Must be greater than - zero. - * - __u32 - - ``reserved``\ [4] - - Reserved for future extensions. Drivers must set the - array to zero. - * - struct :c:type:`v4l2_enc_idx_entry` - - ``entry``\ [``V4L2_ENC_IDX_ENTRIES``] - - Meta data about a compressed video stream. Each element of the - array corresponds to one picture, sorted in ascending order by - their ``offset``. - - - -.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| - -.. c:type:: v4l2_enc_idx_entry - -.. flat-table:: struct v4l2_enc_idx_entry - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u64 - - ``offset`` - - The offset in bytes from the beginning of the compressed video - stream to the beginning of this picture, that is a *PES packet - header* as defined in :ref:`mpeg2part1` or a *picture header* as - defined in :ref:`mpeg2part2`. When the encoder is stopped, the - driver resets the offset to zero. - * - __u64 - - ``pts`` - - The 33 bit *Presentation Time Stamp* of this picture as defined in - :ref:`mpeg2part1`. - * - __u32 - - ``length`` - - The length of this picture in bytes. - * - __u32 - - ``flags`` - - Flags containing the coding type of this picture, see - :ref:`enc-idx-flags`. - * - __u32 - - ``reserved``\ [2] - - Reserved for future extensions. Drivers must set the array to - zero. - - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. _enc-idx-flags: - -.. flat-table:: Index Entry Flags - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 4 - - * - ``V4L2_ENC_IDX_FRAME_I`` - - 0x00 - - This is an Intra-coded picture. - * - ``V4L2_ENC_IDX_FRAME_P`` - - 0x01 - - This is a Predictive-coded picture. - * - ``V4L2_ENC_IDX_FRAME_B`` - - 0x02 - - This is a Bidirectionally predictive-coded picture. - * - ``V4L2_ENC_IDX_FRAME_MASK`` - - 0x0F - - *AND* the flags field with this mask to obtain the picture coding - type. - - -Return Value -============ - -On success 0 is returned, on error -1 and the ``errno`` variable is set -appropriately. The generic error codes are described at the -:ref:`Generic Error Codes <gen-errors>` chapter. |