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avconv -f sndio -i /dev/audio0 /tmp/oss.wav
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@section video4linux and video4linux2
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@section video4linux2
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Video4Linux and Video4Linux2 input video devices.
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Video4Linux2 input video device.
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The name of the device to grab is a file device node, usually Linux
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systems tend to automatically create such nodes when the device
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kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
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Video4Linux and Video4Linux2 devices only support a limited set of
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Video4Linux2 devices usually support a limited set of
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@var{width}x@var{height} sizes and framerates. You can check which are
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supported for example with the command @file{dov4l} for Video4Linux
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devices and using @command{-list_formats all} for Video4Linux2 devices.
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If the size for the device is set to 0x0, the input device will
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try to autodetect the size to use.
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Only for the video4linux2 device, if the frame rate is set to 0/0 the
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input device will use the frame rate value already set in the driver.
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Video4Linux support is deprecated since Linux 2.6.30, and will be
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dropped in later versions.
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Follow some usage examples of the video4linux devices with the av*
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supported using @command{-list_formats all} for Video4Linux2 devices.
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Some usage examples of the video4linux2 devices with avconv and avplay:
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# Grab and show the input of a video4linux device, frame rate is set
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# to the default of 25/1.
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avplay -s 320x240 -f video4linux /dev/video0
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# Grab and show the input of a video4linux2 device, autoadjust size.
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avplay -f video4linux2 /dev/video0
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# Grab and record the input of a video4linux2 device, autoadjust size,
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# frame rate value defaults to 0/0 so it is read from the video4linux2
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avconv -f video4linux2 -i /dev/video0 out.mpeg
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# Grab and show the input of a video4linux2 device.
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avplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
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# Grab and record the input of a video4linux2 device, leave the
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framerate and size as previously set.
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avconv -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
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@var{hostname}:@var{display_number}.@var{screen_number} specifies the
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X11 display name of the screen to grab from. @var{hostname} can be
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ommitted, and defaults to "localhost". The environment variable
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omitted, and defaults to "localhost". The environment variable
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@env{DISPLAY} contains the default display name.
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@var{x_offset} and @var{y_offset} specify the offsets of the grabbed