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I am writing an application which is based on Motion. Motion allows me to define a video4linux loopback device:

# Output images to a video4linux loopback device
# The value '-' means next available (default: not defined)
; video_pipe value

# Output motion images to a video4linux loopback device
# The value '-' means next available (default: not defined)
; motion_video_pipe value

Motion already accesses the webcam to detect motion, now I would like to access images of the webcam, too. I think the loopback device is the right thing to do this.

But what do I have to do exactly? Do I have to configure another(?) video4linux device and add it in the configuration? Motion offers documentation about this topic. But I find it hard to get starting, as I am still troubled with how the whole architecture is working.

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up vote 2 down vote accepted

you can try this link : http://www.lavrsen.dk/foswiki/bin/view/Motion/LoopbackDevice.

"When you install the video loopback device it will create an input - for example /dev/video5 and an output - for example /dev/video6. You can then tell motion to "pipe" the video signal to the /dev/video5 and look at the pictures live using e.g. Camstream on /dev/video6. Camstream is "fooled" to think it is looking at a real camera."

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RevMoon is this what you are looking for ? If so, then accept this one as the answer, otherwise state in a comment why it is not helpful. – The Dark Knight Sep 27 '12 at 18:42
No worries, I would have in time. Just saw your answer not before now. Perfect thanks, I haven't found this. But this explains it. Then I can access it as any other application would do, too. – RevMoon Sep 27 '12 at 19:03
you are welcome . – The Dark Knight Sep 27 '12 at 19:16

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