1. A method for training a vehicle detection system used in a street occupancy estimation of stationary vehicles, the method comprising: defining first and second areas on an image plane of at least one image capture device associated with monitoring for detection of vehicles, wherein the first area includes an on-street parking lane and the second area includes a traffic lane adjacent to the on-street parking lane; receiving video-data from a sequence of frames captured from the image capture device; determining candidate frames that include sample objects relevant to a classification task in the second area; extracting the sample objects from the candidate frames; extracting features of each extracted sample object; assigning labels to the each extracted sample object; training at least one classifier using the extracted features of the labeled objects; and, using the at least one trained classifier to classify a vehicle class of a stationary vehicle detected in the first area.