The Design of Software (CLOSED)

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Video Motion Detection


I was looking for a motion detection algorithm tutorial. I have used Google, but I just can't find anything explaing the process in a clear way.... code sample would be great, but just a clear explaination of the detect-algorithm is the main goal.

Guyon Morée Send private email
Thursday, May 26, 2005
Are you looking to detect motion or to track it?

Tracking black art and papers can be found in academic papers.

Detecting motion can be fairly trivial depending on your application. The simplest approach is simply to measure the difference between two images taken at different points in time. If there's a difference, something has moved (all else being equal (which it usually isn't) and assuming image noise isn't an issue (which it is)).

Domo Arigato
Mr. Roboto
Thursday, May 26, 2005
If you take the Fourier transform of the subsequent frames, it will be easier to work on the frequency domain instead of time domain when dealing with the differences.

For digitized images, a discrete version of the Fourier transform is available, it's called FFT (Fast Fourier Transform).
Hakan Send private email
Thursday, May 26, 2005
It depends very much what kind of object you want to detect the motion of, and what you want to do with the motion data.

Detecting enemy tanks and prediction their vector in 3D space over time is very different from detecting a moving face, for example.

I made software to detect moving faces, simply by making a "face detector" that runs fast enough so that it can be applied at the framerate of a video camera. It does not classify the face, only recognises it as "a face".

Eigenspace transform assignes a "signature" to the face, so the system follows individual faces around.

You have to provide some more details if you want specific pointers. Is it movement of items on a conveyor belt (2D movement), is the application for optical navigation based on stars like to be found in ICMBs etc..
Frank de Groot Send private email
Friday, May 27, 2005
Alex Drahon Send private email
Saturday, May 28, 2005
wow, thanks, generation5 is a really cool site
Guyon Morée Send private email
Monday, May 30, 2005

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