The paper presents the procedure which automatically and reliably determines the presence of heart enlargement, also known as cardiomegaly, from a chest radiograph. We took advantage of some well-established image processing methods and adapted a few of them to meet our needs. Methods which were used include image filtering with convolution masks, segmentation with thresholding and edge detection. The procedure to detect heart and chest cavity boundaries and the corresponding boundary points using modified and custom image processing methods is presented. The final result represents the confirmation or rejection of cardiomegaly
