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diff --git a/Documentation/media/uapi/v4l/video.rst b/Documentation/media/uapi/v4l/video.rst deleted file mode 100644 index 69603b5efbb5..000000000000 --- a/Documentation/media/uapi/v4l/video.rst +++ /dev/null @@ -1,75 +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 - -.. _video: - -************************ -Video Inputs and Outputs -************************ - -Video inputs and outputs are physical connectors of a device. These can -be for example: RF connectors (antenna/cable), CVBS a.k.a. Composite -Video, S-Video and RGB connectors. Camera sensors are also considered to -be a video input. Video and VBI capture devices have inputs. Video and -VBI output devices have outputs, at least one each. Radio devices have -no video inputs or outputs. - -To learn about the number and attributes of the available inputs and -outputs applications can enumerate them with the -:ref:`VIDIOC_ENUMINPUT` and -:ref:`VIDIOC_ENUMOUTPUT` ioctl, respectively. The -struct :c:type:`v4l2_input` returned by the -:ref:`VIDIOC_ENUMINPUT` ioctl also contains signal -status information applicable when the current video input is queried. - -The :ref:`VIDIOC_G_INPUT <VIDIOC_G_INPUT>` and -:ref:`VIDIOC_G_OUTPUT <VIDIOC_G_OUTPUT>` ioctls return the index of -the current video input or output. To select a different input or output -applications call the :ref:`VIDIOC_S_INPUT <VIDIOC_G_INPUT>` and -:ref:`VIDIOC_S_OUTPUT <VIDIOC_G_OUTPUT>` ioctls. Drivers must -implement all the input ioctls when the device has one or more inputs, -all the output ioctls when the device has one or more outputs. - -Example: Information about the current video input -================================================== - -.. code-block:: c - - struct v4l2_input input; - int index; - - if (-1 == ioctl(fd, VIDIOC_G_INPUT, &index)) { - perror("VIDIOC_G_INPUT"); - exit(EXIT_FAILURE); - } - - memset(&input, 0, sizeof(input)); - input.index = index; - - if (-1 == ioctl(fd, VIDIOC_ENUMINPUT, &input)) { - perror("VIDIOC_ENUMINPUT"); - exit(EXIT_FAILURE); - } - - printf("Current input: %s\\n", input.name); - - -Example: Switching to the first video input -=========================================== - -.. code-block:: c - - int index; - - index = 0; - - if (-1 == ioctl(fd, VIDIOC_S_INPUT, &index)) { - perror("VIDIOC_S_INPUT"); - exit(EXIT_FAILURE); - } |