1. A method for detecting a clear driving path for a vehicle, said method comprising: processing images from a camera to produce feature data for one or more patches from each of the images; analyzing the feature data for the one or more patches using a trained classifier to determine a probability value; selecting patches whose probability value exceeds a first probability threshold value as positive test samples; using locations of the one or more patches to identify which training samples and which of the positive test samples should be used to adaptively train the trained classifier, where the locations are defined in terms of feature vector space; and making a clear-driving-path or non-clear-path determination for each of the one or more patches based on the probability value.