比较python中的LBP
作者:互联网
我生成了这样的纹理图像
我必须比较两个纹理.我用直方图比较法.
image_file = 'output_ori.png'
img_bgr = cv2.imread(image_file)
height, width, channel = img_bgr.shape
hist_lbp = cv2.calcHist([img_bgr], [0], None, [256], [0, 256])
print("second started")
image_fileNew = 'output_scan.png'
img_bgr_new = cv2.imread(image_fileNew)
height_new, width_new, channel_new = img_bgr_new.shape
print("second lbp")
hist_lbp_new = cv2.calcHist([img_bgr_new], [0], None, [256], [0, 256])
print("compar started")
compare = cv2.compareHist(hist_lbp, hist_lbp_new, cv2.HISTCMP_CORREL)
print(compare)
但这种方法效果不佳.它显示了两种不同图像纹理的类似结果.此外,它没有显示太多的变化来识别Print&扫描效果.我如何比较纹理?我想过分析GLCM特征.
import cv2
import numpy as np
from skimage.feature import greycomatrix
img = cv2.imread('images/noised_img1.jpg', 0)
image = np.array(img, dtype=np.uint8)
g = greycomatrix(image, [1, 2], [0, np.pi/2], levels=4, normed=True, symmetric=True)
contrast = greycoprops(g, 'contrast')
print(contrast)
在这个方法中,我得到输出为2 * 2矩阵.如何比较几个特征的两个矩阵,如对比度,相似性,同质性,ASM,能量和相关性?
评论澄清
import numpy as np
from PIL import Image
class LBP:
def __init__(self, input, num_processes, output):
# Convert the image to grayscale
self.image = Image.open(input).convert("L")
self.width = self.image.size[0]
self.height = self.image.size[1]
self.patterns = []
self.num_processes = num_processes
self.output = output
def execute(self):
self._process()
if self.output:
self._output()
def _process(self):
pixels = list(self.image.getdata())
pixels = [pixels[i * self.width:(i + 1) * self.width] for i in range(self.height)]
# Calculate LBP for each non-edge pixel
for i in range(1, self.height - 1):
# Cache only the rows we need (within the neighborhood)
previous_row = pixels[i - 1]
current_row = pixels[i]
next_row = pixels[i + 1]
for j in range(1, self.width - 1):
# Compare this pixel to its neighbors, starting at the top-left pixel and moving
# clockwise, and use bit operations to efficiently update the feature vector
pixel = current_row[j]
pattern = 0
pattern = pattern | (1 << 0) if pixel < previous_row[j-1] else pattern
pattern = pattern | (1 << 1) if pixel < previous_row[j] else pattern
pattern = pattern | (1 << 2) if pixel < previous_row[j+1] else pattern
pattern = pattern | (1 << 3) if pixel < current_row[j+1] else pattern
pattern = pattern | (1 << 4) if pixel < next_row[j+1] else pattern
pattern = pattern | (1 << 5) if pixel < next_row[j] else pattern
pattern = pattern | (1 << 6) if pixel < next_row[j-1] else pattern
pattern = pattern | (1 << 7) if pixel < current_row[j-1] else pattern
self.patterns.append(pattern)
def _output(self):
# Write the result to an image file
result_image = Image.new(self.image.mode, (self.width - 2, self.height - 2))
result_image.putdata(self.patterns)
result_image.save("output.png")
我用这段代码生成了纹理.我有纹理,我有计算纹理属性的方法,但问题是如何识别两个纹理之间的相似性.
解决方法:
假设您有两个类,例如蒸粗麦粉和针织品,并且您希望将未知的彩色图像分类为蒸粗麦粉或针织品.一种可能的方法是:
>将彩色图像转换为灰度.
>计算本地二进制模式.
>计算局部二进制模式的归一化直方图.
以下代码段实现了此方法:
import numpy as np
from skimage import io, color
from skimage.feature import local_binary_pattern
def lbp_histogram(color_image):
img = color.rgb2gray(color_image)
patterns = local_binary_pattern(img, 8, 1)
hist, _ = np.histogram(patterns, bins=np.arange(2**8 + 1), density=True)
return hist
couscous = io.imread('https://i.stack.imgur.com/u3xLI.png')
knitwear = io.imread('https://i.stack.imgur.com/Zj14J.png')
unknown = io.imread('https://i.stack.imgur.com/JwP3j.png')
couscous_feats = lbp_histogram(couscous)
knitwear_feats = lbp_histogram(knitwear)
unknown_feats = lbp_histogram(unknown)
然后,您需要测量未知图像的LBP直方图与表示两个所考虑的类的图像的直方图之间的相似性(或不相似性).直方图之间的欧几里德距离是一种流行的不相似度量.
In [63]: from scipy.spatial.distance import euclidean
In [64]: euclidean(unknown_feats, couscous_feats)
Out[64]: 0.10165884804845844
In [65]: euclidean(unknown_feats, knitwear_feats)
Out[65]: 0.0887492936776889
在这个例子中,未知图像将被归类为针织品,因为不同的未知 – 蒸粗麦粉大于不相似的未知针织品.这与未知图像实际上是不同类型的针织物这一事实非常一致.
import matplotlib.pyplot as plt
hmax = max([couscous_feats.max(), knitwear_feats.max(), unknown_feats.max()])
fig, ax = plt.subplots(2, 3)
ax[0, 0].imshow(couscous)
ax[0, 0].axis('off')
ax[0, 0].set_title('Cous cous')
ax[1, 0].plot(couscous_feats)
ax[1, 0].set_ylim([0, hmax])
ax[0, 1].imshow(knitwear)
ax[0, 1].axis('off')
ax[0, 1].set_title('Knitwear')
ax[1, 1].plot(knitwear_feats)
ax[1, 1].set_ylim([0, hmax])
ax[1, 1].axes.yaxis.set_ticklabels([])
ax[0, 2].imshow(unknown)
ax[0, 2].axis('off')
ax[0, 2].set_title('Unknown (knitwear)')
ax[1, 2].plot(unknown_feats)
ax[1, 1].set_ylim([0, hmax])
ax[1, 2].axes.yaxis.set_ticklabels([])
plt.show(fig)
标签:python,image-processing,scikit-image,lbph-algorithm,glcm 来源: https://codeday.me/bug/20190710/1425296.html