Define area to capture image

Hi, my final year project is about illegal parking detection using image processing. We are trying to develop a system that detects Illegally parked vehicles. Is there a way you can make the webcam capture an image when there is an object in the defined area (no parking) Some help would be useful. Thanks :)

Answer 1

[Image Analyst]

Snap pictures continously. The parking space should be pretty uniform. If it's not, a car is parked there.

croppedImage = imcrop(rgbImage, someROI);
sd = std(croppedImage(:,:, 2)); % Take std dev of green channel.
if sd > maxAllowableSD
    % Parking space is no longer empty
end