1. A computer implemented method of detecting a vehicle in video, the video acquired from a fixed parking occupancy video camera including a field of view associated with a parking region, the method comprising: a) capturing video from the fixed parking occupancy video camera; and b) performing a sliding window-based space search for a vehicle within the captured video, the sliding window-based space search extracting one or more features associated with each of a plurality of windows and accessing an operatively associated second classifier to classify each window as including a vehicle or not including a vehicle, wherein the second classifier is trained using high confidence training samples acquired from samples of video obtained from the fixed parking occupancy video camera operatively associated with a first classifier, the samples including positive (vehicle) samples of video and negative (non-vehicle) samples of video, and wherein the first classifier is trained with video captured from another fixed parking occupancy video camera including a different field of view associated with another parking region.