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.TH DV4L 1
.SH NAME
dv4l \- make a dv1394 camcorder available for video4linux programs
.SH SYNOPSIS
.BI "dv4l [" options "]"
.sp
options (shortest form):
.B [\-cdrsvh]
.SH DESCRIPTION
.B dv4l
enables programs using the video4linux API to access a dv1394
(Firewire) camcorder. It pushes the video stream to an input
device provided by the
.B vloopback
kernel module.
Before starting
.B dv4l
, make sure that the
.B vloopback
module is present in the kernel.
See
http://www.lavrsen.dk/twiki/bin/view/Motion/VideoFourLinuxLoopbackDevice
(without the dash) for information about this kernel module.
Check your 1394 driver config by starting
\ \ $ gst-launch-0.10 dv1394src \\! dvdemux \\! dvdec \\! xvimagesink
from your shell. After turning on your camera, a video window should appear.
If this works, dv4l should work as well.
Make sure that your camera is on before starting a video4linux
program.
.SH OPTIONS
.TP
.BI "\-c, \-\-color\-correction"
Set this option if red objects look blue.
.TP
.BI "\-d, \-\-device" \ device-name
Use device-name as vloopback input device. If this option
is omitted,
.B dv4l
will automatically look for an appropriate device.
.TP
.BI "\-r, \-\-rgb\-only
Set this option to prevent V4L applications from choosing
YUV palettes. Try this option if you get low frame rates.
.TP
.BI "\-s, \-\-size" \ WxH
Set capture size and use slower copy mode, only required for some
V4L applications. When using this option, V4L applications can't
change the capture size.
.TP
.BI "\-v, \-\-verbose" \ level
Set the amount of debugging messages. A level of 0 means no output at all, 1
is the default, 3 enables all messages.
.TP
.B "\-h, \-\-help"
displays a help message
.SH EXAMPLES
In most cases,
.B dv4l
can be started without any options. Kopete, however needs the --size
option, with a resolution of 320x240:
\ \ dv4l -s 320x240
Like kopete, gqcam needs the \-\-size option, but supports arbitrary
resolutions:
\ \ dv4l -s 635x360
.B dv4l
will do the scaling.
.SH LIMITATIONS
.B dv4l
does not support adjustment of color, brightness and similar parameters.
It supports only RGB24 and YUV420P palettes. Some V4L programs
may not work as they require different palettes.
It supports only a single dv1394 camera.
Skype v2.0beta seems to have problems with vloopback
and does NOT work with dv4l. Try
.I dv4lstart
instead.
.SH SEE ALSO
dv4lstart(1)
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