图像灰度伽玛变换

import cv2
import numpy as np
import matplotlib.pyplot as plt
def gamma_plot(c,v):
    x=np.arange(0,256,0.01)
    y=c*x**v
    plt.plot(x,y,"r",linewidth=1)
    plt.rcParams["font.sans-serif"]=["SimHei"]
    plt.title("伽玛变换函数")
    plt.xlim([0,255])
    plt.ylim([0,255])
    plt.show()
#伽玛变换
def gamma(img,c,v):
    lut=np.zeros(256,dtype=np.float32)
    for i in range(256):
        lut[i]=c*i**v
    #灰度值的映射
    output=cv2.LUT(img,lut)
    output=np.uint8(output+0.5)
    return output
img=cv2.imread("C:/Users/xpp/Desktop/Lena.png")
grayImage=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
height,width=grayImage.shape[:2]
gamma_plot(0.0000005,4)
result=gamma(grayImage,0.0000005,4)
cv2.imshow("original",grayImage)
cv2.imshow("result",result)
if cv2.waitKey()==27:
    cv2.destroyAllWindows()