Radiographs as medical documents: automating standard measurements

A program has been initiated to automate certain radiographic measurements. The edge detection step is discussed. An edge detection model is presented for standard radiographs, which will be the basis for the measurements step. In particular, the edges of interest are modeled as a linear combination of basis functions. The problem of edge detection is then presented as a supervised pattern recognition problem in which the parameters of the basis functions are learned during the training phase, and the recognition phase uses these learned parameters to locate pixels that belong to edges. Since edges may appear in any direction, the mathematical tools to determine the gradient direction of the edge are developed. >