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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _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 or RGB connectors. 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 <vidioc-enuminput>` and
+:ref:`VIDIOC_ENUMOUTPUT <vidioc-enumoutput>` ioctl, respectively. The
+struct :ref:`v4l2_input <v4l2-input>` returned by the
+``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.
+
+
+.. 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);
+
+
+.. code-block:: c
+
+    int index;
+
+    index = 0;
+
+    if (-1 == ioctl(fd, VIDIOC_S_INPUT, &index)) {
+        perror("VIDIOC_S_INPUT");
+        exit(EXIT_FAILURE);
+    }
+
+
+
+
+.. ------------------------------------------------------------------------------
+.. This file was automatically converted from DocBook-XML with the dbxml
+.. library (https://github.com/return42/sphkerneldoc). The origin XML comes
+.. from the linux kernel, refer to:
+..
+.. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook
+.. ------------------------------------------------------------------------------