python opencv cv2 基础操作4 Extracting Features

#coding=utf-8 import cv2 #cv2.__version__==3.2.0 import numpy as np #Extracting Features #Detecting the corners # img=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) # gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY) # gray = np.float32(gray) # dst = cv2.cornerHarris(gray, 4,5, 0.04) # to detect only sharp corners # # dst = cv2.cornerHarris(gray, 14, 5, 0.04) # to detect soft corners # # Result is dilated for marking the corners # dst = cv2.dilate(dst,None) # # Threshold for an optimal value, it may vary depending on the image. # img[dst > 0.01*dst.max()] = [0,0,0] # cv2.imshow('Harris Corners',img) # cv2.waitKey() ##################### # corners = cv2.goodFeaturesToTrack(gray, 7, 0.05, 25) # corners = np.float32(corners) # for item in corners: # x, y = item[0] # cv2.circle(img, (x,y), 5, 255, -1) # cv2.imshow("Top 'k' features", img) # cv2.waitKey() #################################################### #SIFT input_image=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) gray_image = cv2.cvtColor(input_image,cv2.COLOR_BGR2GRAY) dummy = np.zeros((1,1)) sift = cv2.xfeatures2d.SIFT_create() keypoints1, descriptors1 = sift.detectAndCompute(gray_image,None) print('SIFT features',len(keypoints1)) input_image = cv2.drawKeypoints(input_image, keypoints1,dummy, flags=cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv2.imshow('SIFT features', input_image) # cv2.waitKey() ####################################################### #SURF input_image=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) gray_image = cv2.cvtColor(input_image,cv2.COLOR_BGR2GRAY) dummy = np.zeros((1,1)) surf = cv2.xfeatures2d.SURF_create() keypoints1, descriptors1 = surf.detectAndCompute(gray_image,None) print('SURF_create',len(keypoints1)) input_image = cv2.drawKeypoints(input_image, keypoints1,dummy, flags=cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv2.imshow('SURF_create', input_image) # cv2.waitKey() ####################################################### #StarDetector input_image=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) gray_image = cv2.cvtColor(input_image,cv2.COLOR_BGR2GRAY) dummy = np.zeros((1,1)) StarDetector = cv2.xfeatures2d.StarDetector_create() keypoints=StarDetector.detect(gray_image) # keypoints1, descriptors1 = descriptor_sift.detectAndCompute(gray_image,None) print('Star_create',len(keypoints1)) input_image = cv2.drawKeypoints(input_image, keypoints1,dummy, flags=cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv2.imshow('Star_create', input_image) # cv2.waitKey() #FAST not have descriptor use BRIEF input_image=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) gray_image = cv2.cvtColor(input_image,cv2.COLOR_BGR2GRAY) dummy = np.zeros((1,1)) fast = cv2.FastFeatureDetector_create() # Initiate BRIEF extractor brief = cv2.xfeatures2d.BriefDescriptorExtractor_create() keypoints=fast.detect(gray_image) print('FAST_create',len(keypoints)) # compute the descriptors with BRIEF keypoints, descriptors = brief.compute(gray_image, keypoints) input_image = cv2.drawKeypoints(input_image, keypoints,dummy, flags=cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv2.imshow('FAST_create', input_image) # cv2.waitKey() ####################################################### #ORB not have descriptor use BRIEF input_image=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) gray_image = cv2.cvtColor(input_image,cv2.COLOR_BGR2GRAY) dummy = np.zeros((1,1)) orb = cv2.ORB_create() keypoints, descriptors1=orb.detectAndCompute(gray_image,None) # keypoints=org.detect(gray_image) print('ORB_create',len(keypoints)) input_image = cv2.drawKeypoints(input_image, keypoints,dummy, flags=cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv2.imshow('ORB_create', input_image) # cv2.waitKey() ####################################################### #MSER not have descriptor use BRIEF input_image=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) gray_image = cv2.cvtColor(input_image,cv2.COLOR_BGR2GRAY) dummy = np.zeros((1,1)) mser = cv2.MSER_create() # Initiate BRIEF extractor brief = cv2.xfeatures2d.BriefDescriptorExtractor_create() keypoints=mser.detect(gray_image) print('MSER_create:',len(keypoints)) # compute the descriptors with BRIEF keypoints, descriptors = brief.compute(gray_image, keypoints) input_image = cv2.drawKeypoints(input_image, keypoints,dummy, flags=cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv2.imshow('MSER_create', input_image) # cv2.waitKey() ####################################################### #BRISK not have descriptor use BRIEF input_image=cv2.imread('corner.bmp',cv2.IMREAD_ANYCOLOR) gray_image = cv2.cvtColor(input_image,cv2.COLOR_BGR2GRAY) dummy = np.zeros((1,1)) brisk = cv2.BRISK_create() keypoints, descriptors1=brisk.detectAndCompute(gray_image,None) input_image = cv2.drawKeypoints(input_image, keypoints,dummy, flags=cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS) cv2.imshow('BRISK_create', input_image) cv2.waitKey()