media/v4l/dev-decoder.rst

65    height for given coded resolution.
67 coded resolution
68    stream resolution in pixels aligned to codec and hardware requirements;
69    typically visible resolution rounded up to full macroblocks;
70    see also: visible resolution.
73    width for given coded resolution.
139    height in pixels for given source resolution; relevant to encoders only.
141 source resolution
142    resolution in pixels of source frames being source to the encoder and
143    subject to further cropping to the bounds of visible resolution; relevant to
147    width in pixels for given source resolution; relevant to encoders only.
154    for example: coded resolution, visible resolution, codec profile.
157    height for given visible resolution; display height.
159 visible resolution
160    stream resolution of the visible picture, in pixels, to be used for
161    display purposes; must be smaller or equal to coded resolution;
162    display resolution.
165    width for given visible resolution; display width.
225      parser and if the decoder supports dynamic resolution changes.
268          coded resolution of the stream; required only if it cannot be parsed
270          use this resolution as a placeholder resolution that will likely change
271          as soon as it can parse the actual coded resolution from the stream.
286      resolution instantly based on the width and height returned by
288      However, for coded formats that include stream resolution information,
355 4.  **This step only applies to coded formats that contain resolution information
371     * If the client has not set the coded resolution of the stream on its own,
393        those parsed by the decoder, a `Dynamic Resolution Change` will be
416           frame buffer resolution for the decoded frames.
435 2.  **Optional.** Acquire the visible resolution via
449           the visible rectangle; it must fit within the frame buffer resolution
455           corresponds to the coded resolution of the stream.
460           will be equal to the visible resolution of the stream.
463           the rectangle within the coded resolution to be output to
507        hardware limitations). After parsing a resolution of 1920x1088 or lower,
509        but after parsing resolution higher than 1920x1088, the decoder will not
510        return RGB, unsupported for this resolution.
512        However, subsequent resolution change event triggered after
513        discovering a resolution change within the same stream may switch
514        the stream into a lower resolution and :c:func:`VIDIOC_ENUM_FMT`
530          frame buffer resolution of the decoded stream; typically unchanged from
535      to their default values, based on the new resolution, as described in the
558          the visible rectangle; it must fit within the frame buffer resolution
654     resolution changes can be accommodated.
668           a format representing the maximum framebuffer resolution to be
688        * set width and height of the ``OUTPUT`` format to desired coded resolution to
787   ``V4L2_EVENT_SRC_CH_RESOLUTION`` is pending, the `Dynamic Resolution
876    A seek may result in the `Dynamic Resolution Change` sequence being
913 Dynamic Resolution Change
916 Streams that include resolution metadata in the bytestream may require switching
917 to a different resolution during the decoding.
921    Not all decoders can detect resolution changes. Those that do set the
929 * coded resolution (``OUTPUT`` width and height),
931 * visible resolution (selection rectangles),
939 1.  After encountering a resolution change in the stream, the decoder sends a
946        values applying to the stream after the resolution change, including
950     the resolution change point.
985    During the resolution change sequence, the ``OUTPUT`` queue must remain
990    queue and this remains true for the duration of the entire resolution change
1032      such as the `Dynamic Resolution Change` sequence, before continuing with