1V4L2-CTL(1) User Commands V4L2-CTL(1)
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6 v4l2-ctl - An application to control video4linux drivers
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9 v4l2-ctl [-h] [-d <dev>] [many other options]
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12 The v4l2-ctl tool is used to control video4linux devices, either video,
13 vbi, radio or swradio, both input and output. It is able to control al‐
14 most any aspect of such devices covering the full V4L2 API.
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18 -d, --device <dev>
19 Use device <dev> as the V4L2 device. if <dev> starts with a
20 digit, then /dev/video<dev> is used Otherwise if -z was speci‐
21 fied earlier, then <dev> is the entity name or interface ID (if
22 prefixed with 0x) as found in the topology of the media device
23 with the bus info string as specified by the -z option.
24 -v, --verbose
26 Turn on verbose reporting.
27 --version
29 Show version information.
30 -w, --wrapper
32 Use the libv4l2 wrapper library for all V4L2 device accesses. By
33 default v4l2-ctl will directly access the V4L2 device, but with
34 this option all access will go via this wrapper library.
35 -h, --help
37 Prints the help message.
38 --help-io
40 Prints the help message for all options that get/set/list inputs
41 and outputs, both video and audio.
42 --help-misc
44 Prints the help message for miscellaneous options.
45 --help-overlay
47 Prints the help message for all options that get/set/list over‐
48 lay and framebuffer formats.
49 --help-sdr
51 Prints the help message for all options that get/set/list soft‐
52 ware defined radio formats.
53 --help-selection
55 Prints the help message for all options that deal with selec‐
56 tions (cropping and composing).
57 --help-stds
59 Prints the help message for all options that deal with SDTV
60 standards and Digital Video timings.
61 --help-streaming
63 Prints the help message for all options that deal with stream‐
64 ing.
65 --help-subdev
67 Prints the help message for all options that deal with v4l-sub‐
68 devX devices.
69 --help-tuner
71 Prints the help message for all options that deal with tuners
72 and modulators.
73 --help-vbi
75 Prints the help message for all options that get/set/list VBI
76 formats.
77 --help-vidcap
79 Prints the help message for all options that get/set/list video
80 capture formats.
81 --help-vidout
83 Prints the help message for all options that get/set/list video
84 output formats.
85 --help-edid
87 Prints the help message for all options that get/set EDIDs.
88 --help-all
90 Prints the help message for all options.
91 --all Display all information available.
93 -C, --get-ctrl <ctrl>[,<ctrl>...]
95 Get the value of the controls [VIDIOC_G_EXT_CTRLS].
96 -c, --set-ctrl <ctrl>=<val>[,<ctrl>=<val>...]
98 Set the value of the controls [VIDIOC_S_EXT_CTRLS].
99 -D, --info
101 Show driver info [VIDIOC_QUERYCAP].
102 -e, --out-device <dev>
104 Use device <dev> for output streams instead of the default de‐
105 vice as set with --device. If <dev> starts with a digit, then
106 /dev/video<dev> is used. Otherwise if -z was specified earlier,
107 then <dev> is the entity name or interface ID (if prefixed with
108 0x) as found in the topology of the media device with the bus
109 info string as specified by the -z option.
110 -E, --export-device <dev>
112 Use device <dev> for exporting DMA buffers. If <dev> starts
113 with a digit, then /dev/video<dev> is used. Otherwise if -z was
114 specified earlier, then <dev> is the entity name or interface ID
115 (if prefixed with 0x) as found in the topology of the media de‐
116 vice with the bus info string as specified by the -z option.
117 -z, --media-bus-info <bus-info>
119 Find the media device with the given <bus-info> string. If set,
120 then -d, -e and -E options can use the entity name or interface
121 ID to refer to the device nodes. Example: v4l2-ctl -z plat‐
122 form:vivid-000 -d vivid-000-vid-cap
123 -k, --concise
125 Be more concise if possible.
126 -l, --list-ctrls
128 Display all controls and their values [VIDIOC_QUERYCTRL].
129 -L, --list-ctrls-menus
131 Display all controls and their menus [VIDIOC_QUERYMENU].
132 -r, --subset <ctrl>[,<offset>,<size>]+
134 The subset of the N-dimensional array to get/set for control
135 <ctrl>, for every dimension an (<offset>, <size>) tuple is
136 given.
137 --list-devices
139 List all v4l devices. If -z was given, then list just the de‐
140 vices of the media device with the bus info string as specified
141 by the -z option.
142 --log-status
144 Log the board status in the kernel log [VIDIOC_LOG_STATUS].
145 --get-priority
147 Query the current access priority [VIDIOC_G_PRIORITY].
148 --set-priority <prio>
150 Set the new access priority [VIDIOC_S_PRIORITY]. <prio> is 1
151 (background), 2 (interactive) or 3 (record).
152 --silent
154 Only set the result code, do not print any messages.
155 --sleep <secs>
157 Sleep <secs>, call QUERYCAP and close the file handle.
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160 On success, it returns 0. Otherwise, it will return the error code.
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163 Query the device information of /dev/video1:
164 v4l2-ctl -d1 -D
166 Stream video using MMAP stream I/O from /dev/video0:
168 v4l2-ctl -d0 --stream-mmap
170 Stream one frame of video from /dev/video0 and store it in a file:
172 v4l2-ctl --stream-mmap --stream-count=1 --stream-to=file.raw
174 Stream video from /dev/video0 and stream it over the network:
176 v4l2-ctl --stream-mmap --stream-to-host <hostname>
178 Use 'qvidcap -p' on the host to view the video.
180 Stream video from /dev/video0 using DMABUFs exported from /dev/video2:
182 v4l2-ctl --stream-dmabuf --export-device /dev/video2
184 Stream video from a memory-to-memory device:
186 v4l2-ctl --stream-mmap --stream-out-mmap
188 Stream video from a capture video device (/dev/video1) to an output
190 video device (/dev/video2):
191 v4l2-ctl -d1 --stream-mmap --out-device /dev/video2 --stream-out-
193 dmabuf
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197 This manual page is a work in progress.
198 Bug reports or questions about this utility should be sent to the
200 linux-media@vger.kernel.org mailinglist.
201v4l-utils 1.22.1 March 2015 V4L2-CTL(1)