Lines Matching +full:count +full:- +full:width
1 .. SPDX-License-Identifier: GPL-2.0
6 Memory-to-Memory Stateful Video Decoder Interface
9 A stateful video decoder takes complete chunks of the bytestream (e.g. Annex-B
34 5. Single-planar API (see :ref:`planar-apis`) and applicable structures may be
35 used interchangeably with multi-planar API, unless specified otherwise,
44 .. _decoder-glossary:
72 coded width
73 width for given coded resolution.
79 Good at sub-partitioning the picture into variable sized structures.
103 Instantaneous Decoder Refresh; a type of a keyframe in an H.264/HEVC-encoded
112 block transforms (e.g. H.264, VP8, VP9); codec-specific, but for most of
146 source width
147 width in pixels for given source resolution; relevant to encoders only.
153 additional (non-visual) information contained inside encoded bytestream;
164 visible width
165 width for given visible resolution; display width.
170 .. kernel-render:: DOT
186 qi -> Initialization [ label = "open()" ];
188 Initialization -> CaptureSetup [ label = "CAPTURE\nformat\nestablished" ];
190 CaptureSetup -> Stopped [ label = "CAPTURE\nbuffers\nready" ];
192 Decoding -> ResChange [ label = "Stream\nresolution\nchange" ];
193 Decoding -> Drain [ label = "V4L2_DEC_CMD_STOP" ];
194 Decoding -> EoS [ label = "EoS mark\nin the stream" ];
195 Decoding -> Seek [ label = "VIDIOC_STREAMOFF(OUTPUT)" ];
196 Decoding -> Stopped [ label = "VIDIOC_STREAMOFF(CAPTURE)" ];
197 Decoding -> Decoding;
199 ResChange -> CaptureSetup [ label = "CAPTURE\nformat\nestablished" ];
200 ResChange -> Seek [ label = "VIDIOC_STREAMOFF(OUTPUT)" ];
202 EoS -> Drain [ label = "Implicit\ndrain" ];
204 Drain -> Stopped [ label = "All CAPTURE\nbuffers dequeued\nor\nVIDIOC_STREAMOFF(CAPTURE)" ];
205 Drain -> Seek [ label = "VIDIOC_STREAMOFF(OUTPUT)" ];
207 Seek -> Decoding [ label = "VIDIOC_STREAMON(OUTPUT)" ];
208 Seek -> Initialization [ label = "VIDIOC_REQBUFS(OUTPUT, 0)" ];
210 Stopped -> Decoding [ label = "V4L2_DEC_CMD_START\nor\nVIDIOC_STREAMON(CAPTURE)" ];
211 Stopped -> Seek [ label = "VIDIOC_STREAMOFF(OUTPUT)" ];
224 In particular whether or not the decoder has a full-fledged bytestream
267 ``width``, ``height``
286 resolution instantly based on the width and height returned by
305 ``count``
316 ``count``
321 The actual number of allocated buffers may differ from the ``count``
322 given. The client must check the updated value of ``count`` after the
330 ``count``
344 ``count``
349 The actual number of allocated buffers may differ from the ``count``
350 given. The client must check the updated value of ``count`` after the
387 its own may attempt to set the width and height of the ``OUTPUT`` format
388 to non-zero values matching the coded size of the stream, skip this step
415 ``width``, ``height``
448 ``r.left``, ``r.top``, ``r.width``, ``r.height``
459 contains meaningful picture data (visible area); width and height
464 ``CAPTURE``; defaults to ``V4L2_SEL_TGT_CROP_DEFAULT``; read-only on
478 read-only on hardware without additional compose/scaling capabilities.
529 ``width``, ``height``
550 ``r.left``, ``r.top``, ``r.width``, ``r.height``
553 read-only on hardware without additional compose/scaling capabilities.
557 ``r.left``, ``r.top``, ``r.width``, ``r.height``
609 ``count``
623 ``count``
634 ``count``
639 The actual number of allocated buffers may differ from the ``count``
640 given. The client must check the updated value of ``count`` after the
649 ``count`` field to :c:func:`VIDIOC_REQBUFS`.
658 ``count``
673 ``count``
678 The actual number of allocated buffers may differ from the ``count``
679 given. The client must check the updated value of ``count`` after the
688 * set width and height of the ``OUTPUT`` format to desired coded resolution to
709 format and may be affected by codec-specific extended controls, as stated in
713 buffer queues and memory-to-memory devices. In addition, the order of decoded
759 buffers are out-of-order compared to the ``OUTPUT`` buffers): ``CAPTURE``
807 further operations on corresponding decoder file handle will return the -EIO
851 Some hardware is known to mishandle seeks to a non-resume point. Such an
929 * coded resolution (``OUTPUT`` width and height),
935 * bit-depth of the bitstream has been changed.
964 with ``V4L2_BUF_FLAG_LAST`` will result in a -EPIPE error from
1047 marked with ``V4L2_BUF_FLAG_LAST`` will result in a -EPIPE error from
1067 * ``V4L2_DEC_CMD_START`` - the decoder will not be reset and will resume
1071 ``CAPTURE`` queue - the decoder will resume the operation normally,
1076 ``OUTPUT`` queue - any pending source buffers will be returned to the
1086 will fail with -EBUSY error code if attempted.
1123 return the -EBUSY error code for any such format change attempt.