Adaface Sample OpenCV Questions

You are given two images of a scene taken from different viewpoints, and you want to stitch them together using SIFT feature detection and RANSAC-based homography estimation. You have the following code:

What is the correct way to match the SIFT features between the two images?

A: matches = cv2.BFMatcher(cv2.NORM_L1).knnMatch(des1, des2, k=2)
            B: matches = cv2.BFMatcher(cv2.NORM_L2).match(des1, des2)
            C: matches = cv2.FlannBasedMatcher().knnMatch(des1, des2, k=2)
            D: matches = cv2.DescriptorMatcher_create(cv2.DESCRIPTOR_MATCHER_BRUTEFORCE).match(des1, des2)
            E: matches = cv2.DescriptorMatcher_create(cv2.DESCRIPTOR_MATCHER_FLANNBASED).knnMatch(des1, des2, k=2)
            F: matches = cv2.ORB_create().match(des1, des2)

You are given a video sequence of a moving object, and you want to track the object's position and velocity using a Kalman filter. You have the following code:

What is the correct way to detect the object's position in the frame?

A: object_position = cv2.findChessboardCorners(frame, (7, 7))
            B: object_position = cv2.detectMinEigenValAndRichterTerm(frame)
            C: object_position = cv2.HOGDescriptor().compute(frame)
            D: object_position = cv2.goodFeaturesToTrack(frame, 100, 0.01, 10)
            E: object_position = cv2.circle(frame, (int(frame.shape[1] / 2), int(frame.shape[0] / 2)), 5, (0, 255, 0), -1)