New answers tagged webcam
You can try a Portable freeware Aplication "WebCam On-Off v1.0" it has Cmd suppor too http://www.sordum.org/8585/webcam-on-off-dont-let-your-webcam-spy-on-you/
http://sonnati.wordpress.com/2012/07/02/ffmpeg-the-swiss-army-knife-of-internet-streaming-part-v/ "5. Record a stream endlessly rotating target file" That handles your circular buffer. You might have to do a little experimenting to see what works for you to get the previous 30 seconds. There are a number of ways to do that so it'll be up to the ...
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