图像增强指标介绍:
1.Entropy,信息熵。熵指的是体系的混乱的程度,对焦良好的图像的熵大于没有清晰对焦的图像,因此可以用熵作为一种对焦评价标准。熵越大,图像越清晰。
2.PSNR,峰值信噪比。评价画质客观量。PSNR越大,代表着图像质量越好。
3.SSIM,结构相似性。衡量是否符合人眼对图像品质的评判。取值范围【0,1】,值越大表示图像差距越小,质量越好。
4.水下彩色图像质量评估(UCIQE): 利用色度、饱和度和对比度的线性组合进行定量评估,分别量化不均匀的偏色、模糊和低对比度。值越高表示图像质量越好。
5.水下图像质量度量(UIQM): 包含水下图像的三个属性,如水下图像色彩度测量(UICM)水下图像清晰度度量(UISM)和水下图像对比度度量(UIConM)。值越高表示图像质量越好。
########################entropy########################
from PIL import Image
from matplotlib import pyplot as plt
import numpy as np
import scipy as cp
import math
import cv2
#image是增强后图像。在此处修改路径读取增强后图像。
image =cv2.imread(r'/home/kadinu/picture_processing/picture/5.png')
#img2是增强前图像。在此处修改路径读取增强前图像。用于得到SSIM和MSE
#kernel=np.ones((5,5),np.uint8)
#img2=cv2.morphologyEx(image,cv2.MORPH_OPEN, kernel)
img2=cv2.imread(r'/home/kadinu/picture_processing/picture/5.png')
images=np.asarray(image)
plt.subplot(211)
plt.imshow(images)
plt.subplot(212)
images1=images.max(axis=2)
plt.imshow(images1,cmap='gray')
row,col=images1.shape[0],images1.shape[1] # 求图像的规格
images1_size=row*col # 图像像素点的总个数
H1=0
n=np.array([0 for i in range(256)]) # 产生一个 256 维数组
p=[]
for a in images1:
for b in a:
img_level=b # 获取图像的灰度级
n[img_level]+=1 # 统计每个灰度级像素的点数
for k in range(256): # 循环
v=n[k]/images1_size # 计算每一个像素点的概率
p.append(v) # 为什么对数组赋值赋值不了
if v!=0: # 如果像素点的概率不为零
H1 += -v*math.log2(v) # 求熵值的公式
######################## entropy ########################
######################## SSIM,MSE ########################
from skimage.measure import compare_ssim, compare_psnr, compare_mse
import numpy as np
img1 = image
#img2 = cv2.imread(r'/home/kadinu/picture_processing/picture/5.png')
psnr = compare_psnr(img1, img2)
ssim = compare_ssim(img1, img2, multichannel=True) # 对于多通道图像(RGB、HSV等)关键词multichannel要设置为True
mse = compare_mse(img1, img2)
######################## SSIM,MSE ########################
######################## UCIQE,UIQM ########################
import cv2
import math
import numpy as np
hsv = cv2.cvtColor(image, cv2.COLOR_RGB2HSV) # RGB转为HSV
H, S, V = cv2.split(hsv)
delta = np.std(H) /180 #色度的标准差
mu = np.mean(S) /255 #饱和度的平均值
n, m = np.shape(V)
number = math.floor(n*m/100) #所需像素的个数
Maxsum, Minsum = 0, 0
V1, V2 = V /255, V/255
for i in range(1, number+1):
Maxvalue = np.amax(np.amax(V1))
x, y = np.where(V1 == Maxvalue)
Maxsum = Maxsum + V1[x[0],y[0]]
V1[x[0],y[0]] = 0
top = Maxsum/number
for i in range(1, number+1):
Minvalue = np.amin(np.amin(V2))
X, Y = np.where(V2 == Minvalue)
Minsum = Minsum + V2[X[0],Y[0]]
V2[X[0],Y[0]] = 1
bottom = Minsum/number
conl = top-bottom
###对比度
uciqe = 0.4680*delta + 0.2745*conl + 0.2575*mu
###############
def uicm(img):
b, r, g = cv2.split(img)
RG = r - g
YB = (r + g)/2 - b
m, n, o = np.shape(img) #img为三维 rbg为二维
K = m*n
alpha_L = 0.1
alpha_R = 0.1 ##参数α 可调
T_alpha_L = math.ceil(alpha_L*K) #向上取整
T_alpha_R = math.floor(alpha_R*K) #向下取整
RG_list = RG.flatten()
RG_list = sorted(RG_list)
sum_RG = 0
for i in range(T_alpha_L+1, K-T_alpha_R ):
sum_RG = sum_RG + RG_list[i]
U_RG = sum_RG/(K - T_alpha_R - T_alpha_L)
squ_RG = 0
for i in range(K):
squ_RG = squ_RG + np.square(RG_list[i] - U_RG)
sigma2_RG = squ_RG/K
YB_list = YB.flatten()
YB_list = sorted(YB_list)
sum_YB = 0
for i in range(T_alpha_L+1, K-T_alpha_R ):
sum_YB = sum_YB + YB_list[i]
U_YB = sum_YB/(K - T_alpha_R - T_alpha_L)
squ_YB = 0
for i in range(K):
squ_YB = squ_YB + np.square(YB_list[i] - U_YB)
sigma2_YB = squ_YB/K
Uicm = -0.0268*np.sqrt(np.square(U_RG) + np.square(U_YB)) + 0.1586*np.sqrt(sigma2_RG + sigma2_YB)
return Uicm
def EME(rbg, L):
m, n = np.shape(rbg) #横向为n列 纵向为m行
number_m = math.floor(m/L)
number_n = math.floor(n/L)
#A1 = np.zeros((L, L))
m1 = 0
E = 0
for i in range(number_m):
n1 = 0
for t in range(number_n):
A1 = rbg[m1:m1+L, n1:n1+L]
rbg_min = np.amin(np.amin(A1))
rbg_max = np.amax(np.amax(A1))
if rbg_min > 0 :
rbg_ratio = rbg_max/rbg_min
else :
rbg_ratio = rbg_max ###
E = E + np.log(rbg_ratio + 1e-5)
n1 = n1 + L
m1 = m1 + L
E_sum = 2*E/(number_m*number_n)
return E_sum
def UICONM(rbg, L): #wrong
m, n, o = np.shape(rbg) #横向为n列 纵向为m行
number_m = math.floor(m/L)
number_n = math.floor(n/L)
A1 = np.zeros((L, L)) #全0矩阵
m1 = 0
logAMEE = 0
for i in range(number_m):
n1 = 0
for t in range(number_n):
A1 = rbg[m1:m1+L, n1:n1+L]
rbg_min = int(np.amin(np.amin(A1)))
rbg_max = int(np.amax(np.amax(A1)))
plip_add = rbg_max+rbg_min-rbg_max*rbg_min/1026
if 1026-rbg_min > 0:
plip_del = 1026*(rbg_max-rbg_min)/(1026-rbg_min)
if plip_del > 0 and plip_add > 0:
local_a = plip_del/plip_add
local_b = math.log(plip_del/plip_add)
phi = local_a * local_b
logAMEE = logAMEE + phi
n1 = n1 + L
m1 = m1 + L
logAMEE = 1026-1026*((1-logAMEE/1026)**(1/(number_n*number_m)))
return logAMEE
if __name__ == '__main__':
img = image
r, b, g = cv2.split(img)
Uicm = uicm(img)
EME_r = EME(r, 8)
EME_b = EME(b, 8)
EME_g = EME(g, 8)
Uism = 0.299*EME_r + 0.144*EME_b + 0.557*EME_g
Uiconm = UICONM(img, 8)
uiqm = 0.0282*Uicm + 0.2953*Uism + 0.6765*Uiconm
######################## UCIQE,UIQM ########################
print('Entropy:{},PSNR:{},SSIM:{},MSE:{},UCIQE:{},UIQM:{}'.format(H1,psnr, ssim, mse,uciqe,uiqm))
只需要改变注释中的两个路径运行程序即可在终端看到各个值结果。
代码来源于各处,本人仅仅进行调整、整合,侵删。