In this paper, a novel method to measure the footprint pattern of a vehicle tire and its pressure distribution will be put forward. The measurement principle will be presented. The automatic digital image processing methods of the footprint pattern and pressure distribution images, which are used to characterize the footprint pattern, are described. Especially, a novel envelope curve calculation algorithm for finding a pattern boundary is introduced. The experimental results have shown that the methods mentioned in the paper are of robustness and high accuracy.