1. A method of assisting vehicle guidance over terrain, the method comprising: training at least one first classifier technique using a first set of terrain classifier training data, such that the at least one first classifier technique is trained to output at least one probability value usable to classify terrain; using the at least one first trained classifier technique to generate a second set of terrain classifier training data; and training a second classifier technique using the output of the at least one first classifier technique for the second set of terrain classifier training data, and additional data including an image-based representation of the terrain of the second data set, such that the second classifier technique is trained to output a probability value useable to classify terrain.