VIDEO(1) OpenBSD Reference Manual VIDEO(1)NAMEvideo - record or display images from video(4)SYNOPSISvideo [-v] [-a adaptor] [-e encoding] [-f file] [-i input] [-O output]
[-o output] [-r rate] [-s size]
DESCRIPTIONvideo is a utility for reading, writing and displaying streams of raw
video frames. By default frames are read from file and displayed via
Xv(3). The default file is /dev/video. If the -o option is used frames
are read from file and written to output. If the -i option is used
frames are read from input and displayed via Xv(3). If the -O option is
used frames are read from file, written to output and displayed via
Xv(3). The acutance, brightness, contrast, gain, gamma, hue and
saturation controls of file can also be adjusted if file supports these
controls.
The options are as follows:
-a adaptor Index of Xv(3) adaptor to use. The default is 0, the first
adaptor reported by X(7).
-e encoding
Lowercase FOURCC name of video encoding to use. Valid
arguments are `uyvy' and `yuy2'. The default is `yuy2'
unless file is being used and only supports `uyvy', in which
case `uyvy' will be used by default.
-f file video(4) device from which frames will be read. The default
is /dev/video.
-i input File from which frames will be read. If input is `-', frames
will be read from standard input.
-O output File to which frames will be written. If output is `-',
frames will be written to standard output. In contrast to
-o, if this option is used, video will also display the
frames via Xv(3).
-o output File to which frames will be written. If output is `-',
frames will be written to standard output.
-r rate Rate in frames per second at which to read. Must be an
integer greater than 0. If the -r option is not specified,
frames will be read as quickly as possible. If reading from
a video(4) device, frames will be read as quickly as they are
available from the device, but will be displayed and/or
written to output at the rate specified. This is done
because video(4) does not yet support setting the device
frame rate.
-s size Size of frames to read. The format of size is WxH, where W
represents width and H represents height, both expressed as
number of pixels. The default is 640x480. If size does not
contain `x', size is interpreted as only the width. If `x'
is the first character of size, the characters following `x'
are interpreted as the height. If only one of width or
height is specified, the other will be calculated using a 4:3
width:height ratio. For example, if given `-s 640' video
will use a size of `640x480'. When reading from a video(4)
device and displaying the frames on an Xv(3) display, this
option also accepts two special strings, `half' and `full.'
If either `half' or `full' are specified, video will read
frames that are no larger than 2/3 the display width and 2/3
the display height. If `full' is specified, video will
stretch the frame to the full size of the display using Xv(3)
scaling. If video is reading frames from a video(4) device
and the frame size does not match a frame size the device
supports, video will use the largest frame size supported by
the device that is smaller than the specified size.
-v Verbose mode. Multiple instances of this option are allowed.
Each instance increases the level of informational output
printed to stderr.
video will quit reading frames and exit nicely if it receives any of the
following signals: SIGHUP, SIGINT, SIGKILL, SIGTERM, SIGPIPE.
video responds to certain key presses while it is displaying frames. The
keypresses are as follows:
A Increase acutance (sharpness) control of file.
a Decrease acutance (sharpness) control of file.
B Increase brightness control of file.
b Decrease brightness control of file.
C Increase contrast control of file.
c Decrease contrast control of file.
f Toggle full-screen display.
G Increase gain control of file.
g Decrease gain control of file.
H Increase hue control of file.
h Decrease hue control of file.
M Increase gamma control of file.
m Decrease gamma control of file.
p Toggle new frame display.
q Quit video.
r Reset all supported controls of file to their default value.
O Start writing to output. Only meaningful when the -O option is
used.
o Stop writing to output. Only meaningful when the -O option is used.
S Increase saturation control of file.
s Decrease saturation control of file.
EXAMPLES
The following command will read YUY2 encoded, 640 pixel wide and 480
pixel high video frames from /dev/video and display them using the
default Xv(3) adaptor:
$ video
The following command will read YUY2 encoded, 640 pixel wide and 480
pixel high video frames from /dev/video and write them to video.raw at a
rate of 15 frames per second:
$ video-r 15 -o video.raw
The following command will read YUY2 encoded, 640 pixel wide and 480
pixel high video frames from /dev/video, write them to video.raw and
display them using the default Xv(3) adaptor at a rate of 15 frames per
second:
$ video-r 15 -O video.raw
The following command will read YUY2 encoded, 640 pixel wide and 480
pixel high video frames from video.raw and dsplay them on the default
Xv(3) adaptor at a rate of 15 frames per second:
$ video-r 15 -i video.raw
Note that with the first three commands, if /dev/video does not support
640x480 pixels sized frames, the largest frame size smaller than 640x480
will be used, and if /dev/video does not support yuy2 encoding, uyvy will
be used.
SEE ALSOvideo(4)OpenBSD 4.9 October 26, 2010 OpenBSD 4.9
