python使用numpy实现直方图反向投影示例_Python

python使用numpy实现直方图反向投影示例

2020-04-17 10:05益达888 Python

今天小编就为大家分享一篇python使用numpy实现直方图反向投影示例，具有很好的参考价值，希望对大家有所帮助。一起跟随小编过来看看吧

最近跟着OpenCV2-Python-Tutorials在学习python_opencv中直方图的反向投影时，第一种方法是使用numpy实现将图中的红色玫瑰分割出来，教程给的代码缺了一句函数，导致实现不出来。

自己加上了后(也不知到这样加对不对)代码和效果如下：

				?

									代码：

									import cv2

									import numpy as np

									roi = cv2.imread('./data/rose_red.jpg')

									hsv = cv2.cvtColor(roi,cv2.COLOR_BGR2HSV)

									#target is the image we search in

									target = cv2.imread('./data/rose.jpg')

									cv2.imshow('target',target)

									hsvt = cv2.cvtColor(target,cv2.COLOR_BGR2HSV)

									# Find the histograms using calcHist. Can be done with np.histogram2d also

									M = cv2.calcHist([hsv],[0, 1], None, [180, 256], [0, 180, 0, 256] )

									print(M)

									I = cv2.calcHist([hsvt],[0, 1], None, [180, 256], [0, 180, 0, 256] )

									h,s,v = cv2.split(hsvt)

									#斜体是自己加上的

									R=M/I

									print(R.shape)

									B = R[h.ravel(),s.ravel()]

									print(B)

									B = np.minimum(B,1)

									print(B)

									B = B.reshape(hsvt.shape[:2])

									disc = cv2.getStructuringElement(cv2.MORPH_ELLIPSE,(9,9))

									B=cv2.filter2D(B,-1,disc)

									B = np.uint8(B)

									cv2.normalize(B,B,0,255,cv2.NORM_MINMAX)

									cv2.imshow('B',B)

									ret,thresh = cv2.threshold(B,2,255,0)

									cv2.imshow('thresh',thresh)

									res = cv2.bitwise_and(target,target,mask=thresh)

									cv2.imshow('res',res)

									cv2.waitKey(0)