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Diffstat (limited to 'Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst')
-rw-r--r-- | Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst index a53dd3d7f7e2..05835e04c20b 100644 --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst @@ -167,17 +167,37 @@ the ``mbus_code`` field is handled differently: - The hardware decoder for this compressed bytestream format (aka coded format) is capable of parsing a continuous bytestream. Applications do not need to parse the bytestream themselves to find the boundaries - between frames/fields. This flag can only be used in combination with - the ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to compressed + between frames/fields. + + This flag can only be used in combination with the + ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to compressed formats only. This flag is valid for stateful decoders only. * - ``V4L2_FMT_FLAG_DYN_RESOLUTION`` - 0x0008 - Dynamic resolution switching is supported by the device for this compressed bytestream format (aka coded format). It will notify the user via the event ``V4L2_EVENT_SOURCE_CHANGE`` when changes in the video - parameters are detected. This flag can only be used in combination - with the ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to - compressed formats only. It is also only applies to stateful codecs. + parameters are detected. + + This flag can only be used in combination with the + ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to + compressed formats only. This flag is valid for stateful codecs only. + * - ``V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL`` + - 0x0010 + - The hardware encoder supports setting the ``CAPTURE`` coded frame + interval separately from the ``OUTPUT`` raw frame interval. + Setting the ``OUTPUT`` raw frame interval with :ref:`VIDIOC_S_PARM <VIDIOC_G_PARM>` + also sets the ``CAPTURE`` coded frame interval to the same value. + If this flag is set, then the ``CAPTURE`` coded frame interval can be + set to a different value afterwards. This is typically used for + offline encoding where the ``OUTPUT`` raw frame interval is used as + a hint for reserving hardware encoder resources and the ``CAPTURE`` coded + frame interval is the actual frame rate embedded in the encoded video + stream. + + This flag can only be used in combination with the + ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to + compressed formats only. This flag is valid for stateful encoders only. Return Value |