1. A method for extracting coronary vessels from a contrast image, comprising: receiving a plurality of mask images of a coronary region; receiving a contrast image of the coronary region; detecting vessel regions in the contrast image using learning-based vessel segment detection; determining a background region of the contrast image based on the detected vessel regions; estimating background motion between one of the plurality of mask images and the background region of the contrast image; warping said one of the plurality of mask images based on the estimated background motion to generate an estimated background layer; and extracting a coronary vessel layer from the contrast image by subtracting the estimated background layer from the contrast image.