Question

在python 2.7中，我想比较2个图像，如何做到这一点？请一步一步地告诉我。谢谢！

Answer 1

有很多方法可以做。使用一些开源库，例如 OpenCV ， Scikit Learn ， TensorFlow 。

要比较两张图片，您可以在OpenCV中执行类似 Template Matching 的操作

import cv2
import numpy as np
from matplotlib import pyplot as plt
img = cv2.imread('img.jpg', 0)
img2 = img.copy()
template  = cv2.imread('img2.jpg', 0)
w, h = template.shape[::-1]
methods = ['cv2.TM_CCOEFF', 'cv2.TM_CCOEFF_NORMED']
for meth in methods:
    img = img2.copy()
    method = eval(meth)

    res = cv2.matchTemplate(img, template, method)
    min_val, max_val, min_loc, max_loc = cv2.minMaxLoc(res)

    if method in [cv2.TM_SQDIFF or cv2. TM_SQDIFF_NORMED]:
        top_left = min_loc
    else:
        top_left = max_loc

    bottom_right = (top_left[0] + w, top_left[1] + h)

    cv2.rectangle(img, top_left, bottom_right, 255,2)

    plt.subplot(121), plt.imshow(res)
    plt.title('Matching Result'), plt.xticks([]), plt.yticks([])
    plt.subplot(122),plt.imshow(img,cmap = 'gray')
    plt.title('Detected Point'), plt.xticks([]), plt.yticks([])
    plt.suptitle(meth)
    plt.show()

或 Histogram comparison

import cv2
import numpy as np

base = cv2.imread('test4.jpg')
test1 = cv2.imread('test3.jpg')
test2 = cv2.imread('test5.jpg')

rows,cols = base.shape[:2]

basehsv = cv2.cvtColor(base,cv2.COLOR_BGR2HSV)
test1hsv = cv2.cvtColor(test1,cv2.COLOR_BGR2HSV)
test2hsv = cv2.cvtColor(test2,cv2.COLOR_BGR2HSV)

halfhsv = basehsv[rows/2:rows-1,cols/2:cols-1].copy()  # Take lower half of the base image for testing

hbins = 180
sbins = 255
hrange = [0,180]
srange = [0,256]
ranges = hrange+srange  # ranges = [0,180,0,256]
ranges=None


histbase = cv2.calcHist(basehsv,[0,1],None,[180,256],ranges)
cv2.normalize(histbase,histbase,0,255,cv2.NORM_MINMAX)

histhalf = cv2.calcHist(halfhsv,[0,1],None,[180,256],ranges)
cv2.normalize(histhalf,histhalf,0,255,cv2.NORM_MINMAX)

histtest1 = cv2.calcHist(test1hsv,[0,1],None,[180,256],ranges)
cv2.normalize(histtest1,histtest1,0,255,cv2.NORM_MINMAX)

histtest2 = cv2.calcHist(test2hsv,[0,1],None,[180,256],ranges)
cv2.normalize(histtest2,histtest2,0,255,cv2.NORM_MINMAX)

for i in xrange(5):
    base_base = cv2.compareHist(histbase,histbase,i)
    base_half = cv2.compareHist(histbase,histhalf,i)
    base_test1 = cv2.compareHist(histbase,histtest1,i)
    base_test2 = cv2.compareHist(histbase,histtest2,i)
    print "Method: {0} -- base-base: {1} , base-test1: {2}, base_test2: {3}".format(i,base_base,base_test1,base_test2)

Python 2.7 - 如何比较两个图像？

1 个答案: