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diff --git a/Documentation/media/uapi/v4l/streaming-par.rst b/Documentation/media/uapi/v4l/streaming-par.rst deleted file mode 100644 index 425bd0ff1477..000000000000 --- a/Documentation/media/uapi/v4l/streaming-par.rst +++ /dev/null @@ -1,40 +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 - -.. _streaming-par: - -******************** -Streaming Parameters -******************** - -Streaming parameters are intended to optimize the video capture process -as well as I/O. Presently applications can request a high quality -capture mode with the :ref:`VIDIOC_S_PARM <VIDIOC_G_PARM>` ioctl. - -The current video standard determines a nominal number of frames per -second. If less than this number of frames is to be captured or output, -applications can request frame skipping or duplicating on the driver -side. This is especially useful when using the -:ref:`read() <func-read>` or :ref:`write() <func-write>`, which are -not augmented by timestamps or sequence counters, and to avoid -unnecessary data copying. - -Finally these ioctls can be used to determine the number of buffers used -internally by a driver in read/write mode. For implications see the -section discussing the :ref:`read() <func-read>` function. - -To get and set the streaming parameters applications call the -:ref:`VIDIOC_G_PARM <VIDIOC_G_PARM>` and -:ref:`VIDIOC_S_PARM <VIDIOC_G_PARM>` ioctl, respectively. They take -a pointer to a struct :c:type:`v4l2_streamparm`, which -contains a union holding separate parameters for input and output -devices. - -These ioctls are optional, drivers need not implement them. If so, they -return the ``EINVAL`` error code. |