media/v4l/dev-decoder.rst

38 6. i = [a..b]: sequence of integers from a to b, inclusive, i.e. i =
125    SPS/PPS/IDR sequence (H.264/HEVC); a resume point is required to start decode
143    Sequence Parameter Set; a type of metadata entity in an H.264/HEVC bytestream.
362       initialization sequence completes and the frame is decoded.
382        and continue with the `Capture Setup` sequence. However, it must not
393 5.  Continue with the `Capture Setup` sequence.
493        metadata parsed in this initialization sequence, even if more formats
594        :c:func:`VIDIOC_STREAMOFF` on it would abort the sequence and trigger a
696 This state is reached after the `Capture Setup` sequence finishes successfully.
758 before the sequence started. Last of the buffers will have the
759 ``V4L2_BUF_FLAG_LAST`` flag set. To determine the sequence to follow, the client
764   Change` sequence needs to be followed,
766 * if a ``V4L2_EVENT_EOS`` event is pending, the `End of Stream` sequence needs
770 as they happen. The exact operation is documented for each sequence.
786 releasing all buffers and performing the Initialization sequence again.
795 1. Stop the ``OUTPUT`` queue to begin the seek sequence via
852    A seek may result in the `Dynamic Resolution Change` sequence being
854    the part of the stream decoded before the seek. The sequence must be handled
865    seek sequence is performed.
869    queued before the seek sequence may have matching ``CAPTURE`` buffers
870    produced.  For example, given the sequence of operations on the
901 The sequence starts when the decoder detects a coded frame with one or more of
929       ``V4L2_BUF_FLAG_LAST`` flag, similarly to the `Drain` sequence above.
943 The client must continue the sequence as described below to continue the
951        explicit `Drain` sequence. The decoder is stopped after it completes.
957 2.  Continue with the `Capture Setup` sequence.
961    During the resolution change sequence, the ``OUTPUT`` queue must remain
963    abort the sequence and initiate a seek.
967    sequence as well.
970    buffers to/from the ``OUTPUT`` queue even while processing this sequence.
977 sequence described below. After the drain sequence ends, the client has
979 sequence was started.
996       The sequence can be only initiated if both ``OUTPUT`` and ``CAPTURE``
1000       sequence and so the steps described below would not be applicable.
1008      such as the `Dynamic Resolution Change` sequence, before continuing with
1009      the drain sequence,
1053      client and the `Seek` sequence will be triggered.
1057    Once the drain sequence is initiated, the client needs to drive it to
1061    ``V4L2_DEC_CMD_STOP`` again while the drain sequence is in progress and they
1071 will initiate the `Drain` sequence, which the client must handle as described