Detect changes in an avi video

[HDÖ]

I got a surveillance camera with motion sensors, the camera recored movement on a courtyard. So very movement is detected does the camera record a short video sequence. The problem is that the motion detector isn't that good so it might trigger from grass moving in a strong wind, which cause the camera to record quite a few unneeded clips. Therefor I would like someway to detect if there are any major changes in the video sequence, such as a human moving across the courtyard. Basically to filter out all the unneeded clips, the background is more or less static since the only difference is lightning condition.

[poisondeathray]

There are avisynth scripts you can use . It's a scripting language that is very useful for manipulation for various audio/video tasks e.g.

http://forum.doom9.org/showthread.php?p=1628675#post1628675

If you have specific requirements (e.g. maybe there are unique conditions for your camera), the author is very good for feedback and will probably customize the script for you . There is stupid a 5-day wait to register at doom9 so I would register now if you haven't already

[El Heggunte]

Another possibility: in VirtualDub, goto the Options menu, choose Preferences, then adjust the scene change thresholds.