import cv2
import numpy as np

# Load the image
img = cv2.imread("beach.jpg")

# Convert the image to grayscale
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

# Detect corners using the Harris corner detector
corners = cv2.goodFeaturesToTrack(gray, 100, 0.3, 10)

# Calculate the feature vectors using the SIFT descriptor
sift = cv2.xfeatures2d.SIFT_create()
kp, des = sift.detectAndCompute(gray, None)

# Match the feature vectors using the FLANN matcher
matcher = cv2.DescriptorMatcher_create(cv2.DESCRIPTOR_MATCHER_FLANNBASED)
matches = matcher.knnMatch(des, des, k=2)

# Draw the matched keypoints
cv2.drawMatches(img, kp, img, kp, matches, None, flags=cv2.DrawMatchesFlags_NOT_DRAW_SINGLE_POINTS)

# Display the image
cv2.imshow("Image", img)
cv2.waitKey(0)
cv2.destroyAllWindows()