1 .. -*- coding: utf-8; mode: rst -*-
12 VIDIOC_ENUMINPUT - Enumerate video inputs
18 .. c:function:: int ioctl( int fd, VIDIOC_ENUMINPUT, struct v4l2_input *argp )
19 :name: VIDIOC_ENUMINPUT
26 File descriptor returned by :ref:`open() <func-open>`.
34 To query the attributes of a video input applications initialize the
35 ``index`` field of struct :c:type:`v4l2_input` and call the
36 :ref:`VIDIOC_ENUMINPUT` with a pointer to this structure. Drivers
37 fill the rest of the structure or return an ``EINVAL`` error code when the
38 index is out of bounds. To enumerate all inputs applications shall begin
39 at index zero, incrementing by one until the driver returns ``EINVAL``.
42 .. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
44 .. c:type:: v4l2_input
46 .. flat-table:: struct v4l2_input
53 - Identifies the input, set by the application.
56 - Name of the video input, a NUL-terminated ASCII string, for
57 example: "Vin (Composite 2)". This information is intended for the
58 user, preferably the connector label on the device itself.
61 - Type of the input, see :ref:`input-type`.
64 - Drivers can enumerate up to 32 video and audio inputs. This field
65 shows which audio inputs were selectable as audio source if this
66 was the currently selected video input. It is a bit mask. The LSB
67 corresponds to audio input 0, the MSB to input 31. Any number of
68 bits can be set, or none.
70 When the driver does not enumerate audio inputs no bits must be
71 set. Applications shall not interpret this as lack of audio
72 support. Some drivers automatically select audio sources and do
73 not enumerate them since there is no choice anyway.
75 For details on audio inputs and how to select the current input
79 - Capture devices can have zero or more tuners (RF demodulators).
80 When the ``type`` is set to ``V4L2_INPUT_TYPE_TUNER`` this is an
81 RF connector and this field identifies the tuner. It corresponds
82 to struct :c:type:`v4l2_tuner` field ``index``. For
83 details on tuners see :ref:`tuner`.
84 * - :ref:`v4l2_std_id <v4l2-std-id>`
86 - Every video input supports one or more different video standards.
87 This field is a set of all supported standards. For details on
88 video standards and how to switch see :ref:`standard`.
91 - This field provides status information about the input. See
92 :ref:`input-status` for flags. With the exception of the sensor
93 orientation bits ``status`` is only valid when this is the current
97 - This field provides capabilities for the input. See
98 :ref:`input-capabilities` for flags.
101 - Reserved for future extensions. Drivers must set the array to
106 .. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
110 .. flat-table:: Input Types
115 * - ``V4L2_INPUT_TYPE_TUNER``
117 - This input uses a tuner (RF demodulator).
118 * - ``V4L2_INPUT_TYPE_CAMERA``
120 - Any non-tuner video input, for example Composite Video,
121 S-Video, HDMI, camera sensor. The naming as ``_TYPE_CAMERA`` is historical,
122 today we would have called it ``_TYPE_VIDEO``.
123 * - ``V4L2_INPUT_TYPE_TOUCH``
125 - This input is a touch device for capturing raw touch data.
129 .. tabularcolumns:: |p{4.8cm}|p{2.6cm}|p{10.1cm}|
133 .. flat-table:: Input Status Flags
137 * - :cspan:`2` General
138 * - ``V4L2_IN_ST_NO_POWER``
140 - Attached device is off.
141 * - ``V4L2_IN_ST_NO_SIGNAL``
144 * - ``V4L2_IN_ST_NO_COLOR``
146 - The hardware supports color decoding, but does not detect color
147 modulation in the signal.
148 * - :cspan:`2` Sensor Orientation
149 * - ``V4L2_IN_ST_HFLIP``
151 - The input is connected to a device that produces a signal that is
152 flipped horizontally and does not correct this before passing the
154 * - ``V4L2_IN_ST_VFLIP``
156 - The input is connected to a device that produces a signal that is
157 flipped vertically and does not correct this before passing the
159 .. note:: A 180 degree rotation is the same as HFLIP | VFLIP
160 * - :cspan:`2` Analog Video
161 * - ``V4L2_IN_ST_NO_H_LOCK``
163 - No horizontal sync lock.
164 * - ``V4L2_IN_ST_COLOR_KILL``
166 - A color killer circuit automatically disables color decoding when
167 it detects no color modulation. When this flag is set the color
168 killer is enabled *and* has shut off color decoding.
169 * - ``V4L2_IN_ST_NO_V_LOCK``
171 - No vertical sync lock.
172 * - ``V4L2_IN_ST_NO_STD_LOCK``
174 - No standard format lock in case of auto-detection format
176 * - :cspan:`2` Digital Video
177 * - ``V4L2_IN_ST_NO_SYNC``
179 - No synchronization lock.
180 * - ``V4L2_IN_ST_NO_EQU``
183 * - ``V4L2_IN_ST_NO_CARRIER``
185 - Carrier recovery failed.
186 * - :cspan:`2` VCR and Set-Top Box
187 * - ``V4L2_IN_ST_MACROVISION``
189 - Macrovision is an analog copy prevention system mangling the video
190 signal to confuse video recorders. When this flag is set
191 Macrovision has been detected.
192 * - ``V4L2_IN_ST_NO_ACCESS``
194 - Conditional access denied.
195 * - ``V4L2_IN_ST_VTR``
197 - VTR time constant. [?]
201 .. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
203 .. _input-capabilities:
205 .. flat-table:: Input capabilities
210 * - ``V4L2_IN_CAP_DV_TIMINGS``
212 - This input supports setting video timings by using
213 ``VIDIOC_S_DV_TIMINGS``.
214 * - ``V4L2_IN_CAP_STD``
216 - This input supports setting the TV standard by using
218 * - ``V4L2_IN_CAP_NATIVE_SIZE``
220 - This input supports setting the native size using the
221 ``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see
222 :ref:`v4l2-selections-common`.
228 On success 0 is returned, on error -1 and the ``errno`` variable is set
229 appropriately. The generic error codes are described at the
230 :ref:`Generic Error Codes <gen-errors>` chapter.
233 The struct :c:type:`v4l2_input` ``index`` is out of