1 .. -*- coding: utf-8; mode: rst -*-
5 ***********************
6 ioctl VIDIOC_ENUMOUTPUT
7 ***********************
12 VIDIOC_ENUMOUTPUT - Enumerate video outputs
18 .. cpp:function:: int ioctl( int fd, int request, struct v4l2_output *argp )
25 File descriptor returned by :ref:`open() <func-open>`.
36 To query the attributes of a video outputs applications initialize the
37 ``index`` field of struct :ref:`v4l2_output <v4l2-output>` and call
38 the :ref:`VIDIOC_ENUMOUTPUT` ioctl with a pointer to this structure.
39 Drivers fill the rest of the structure or return an ``EINVAL`` error code
40 when the index is out of bounds. To enumerate all outputs applications
41 shall begin at index zero, incrementing by one until the driver returns
47 .. flat-table:: struct v4l2_output
59 - Identifies the output, set by the application.
67 - Name of the video output, a NUL-terminated ASCII string, for
68 example: "Vout". This information is intended for the user,
69 preferably the connector label on the device itself.
77 - Type of the output, see :ref:`output-type`.
85 - Drivers can enumerate up to 32 video and audio outputs. This field
86 shows which audio outputs were selectable as the current output if
87 this was the currently selected video output. It is a bit mask.
88 The LSB corresponds to audio output 0, the MSB to output 31. Any
89 number of bits can be set, or none.
91 When the driver does not enumerate audio outputs no bits must be
92 set. Applications shall not interpret this as lack of audio
93 support. Drivers may automatically select audio outputs without
96 For details on audio outputs and how to select the current output
105 - Output devices can have zero or more RF modulators. When the
106 ``type`` is ``V4L2_OUTPUT_TYPE_MODULATOR`` this is an RF connector
107 and this field identifies the modulator. It corresponds to struct
108 :ref:`v4l2_modulator <v4l2-modulator>` field ``index``. For
109 details on modulators see :ref:`tuner`.
113 - :ref:`v4l2_std_id <v4l2-std-id>`
117 - Every video output supports one or more different video standards.
118 This field is a set of all supported standards. For details on
119 video standards and how to switch see :ref:`standard`.
127 - This field provides capabilities for the output. See
128 :ref:`output-capabilities` for flags.
136 - Reserved for future extensions. Drivers must set the array to
143 .. flat-table:: Output Type
151 - ``V4L2_OUTPUT_TYPE_MODULATOR``
155 - This output is an analog TV modulator.
159 - ``V4L2_OUTPUT_TYPE_ANALOG``
163 - Analog baseband output, for example Composite / CVBS, S-Video,
168 - ``V4L2_OUTPUT_TYPE_ANALOGVGAOVERLAY``
176 .. _output-capabilities:
178 .. flat-table:: Output capabilities
186 - ``V4L2_OUT_CAP_DV_TIMINGS``
190 - This output supports setting video timings by using
195 - ``V4L2_OUT_CAP_STD``
199 - This output supports setting the TV standard by using
204 - ``V4L2_OUT_CAP_NATIVE_SIZE``
208 - This output supports setting the native size using the
209 ``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see
210 :ref:`v4l2-selections-common`.
216 On success 0 is returned, on error -1 and the ``errno`` variable is set
217 appropriately. The generic error codes are described at the
218 :ref:`Generic Error Codes <gen-errors>` chapter.
221 The struct :ref:`v4l2_output <v4l2-output>` ``index`` is out of