OpenCV 去雾

import cv2
import numpy as np
  
def zmMinFilterGray(src, r=7):
    '''最小值滤波，r是滤波器半径'''
    '''if r <= 0:
        return src
    h, w = src.shape[:2]
    I = src
    res = np.minimum(I  , I[[0]+range(h-1)  , :])
    res = np.minimum(res, I[range(1,h)+[h-1], :])
    I = res
    res = np.minimum(I  , I[:, [0]+range(w-1)])
    res = np.minimum(res, I[:, range(1,w)+[w-1]])
    return zmMinFilterGray(res, r-1)'''
    return cv2.erode(src, np.ones((2*r+1, 2*r+1)))                      #使用opencv的erode函数更高效
def guidedfilter(I, p, r, eps):
    '''引导滤波，直接参考网上的matlab代码'''
    height, width = I.shape
    m_I = cv2.boxFilter(I, -1, (r,r))
    m_p = cv2.boxFilter(p, -1, (r,r))
    m_Ip = cv2.boxFilter(I*p, -1, (r,r))
    cov_Ip = m_Ip-m_I*m_p
  
    m_II = cv2.boxFilter(I*I, -1, (r,r))
    var_I = m_II-m_I*m_I
  
    a = cov_Ip/(var_I+eps)
    b = m_p-a*m_I
  
    m_a = cv2.boxFilter(a, -1, (r,r))
    m_b = cv2.boxFilter(b, -1, (r,r))
    return m_a*I+m_b
  
def getV1(m, r, eps, w, maxV1):  #输入rgb图像，值范围[0,1]
    '''计算大气遮罩图像V1和光照值A, V1 = 1-t/A'''
    V1 = np.min(m,2)                                         #得到暗通道图像
    V1 = guidedfilter(V1, zmMinFilterGray(V1,7), r, eps)     #使用引导滤波优化
    bins = 2000
    ht = np.histogram(V1, bins)                              #计算大气光照A
    d = np.cumsum(ht[0])/float(V1.size)
    for lmax in range(bins-1, 0, -1):
        if d[lmax]<=0.999:
            break
    A  = np.mean(m,2)[V1>=ht[1][lmax]].max()
          
    V1 = np.minimum(V1*w, maxV1)                   #对值范围进行限制
      
    return V1,A
  
def deHaze(m, r=81, eps=0.001, w=0.95, maxV1=0.80, bGamma=False):
    Y = np.zeros(m.shape)
    V1,A = getV1(m, r, eps, w, maxV1)               #得到遮罩图像和大气光照
    for k in range(3):
        Y[:,:,k] = (m[:,:,k]-V1)/(1-V1/A)           #颜色校正
    Y =  np.clip(Y, 0, 1)
    if bGamma:
        Y = Y**(np.log(0.5)/np.log(Y.mean()))       #gamma校正,默认不进行该操作
    return Y
  
if __name__ == '__main__':
    m = deHaze(cv2.imread('land.jpg')/255.0)*255
    cv2.imwrite('defog.jpg', m)

转自：https://www.cnblogs.com/zmshy2128/p/6128033.html

视频去雾

if __name__ == '__main__':
    cap = cv2.VideoCapture("1.mp4")
    while(1):
        ret, frame = cap.read()
        m = deHaze(frame/255.0)  #注意，这里不要乘 255
        cv2.imshow("yuan",frame)
        cv2.imshow("this",m)
        if cv2.waitKey(1) & 0xFF == ord('q'):
             break
cap.release()
cv2.destroyAllWindows()