如何使用cv2.kmeans中的标签作为列表的索引?

时间:2017-08-10 12:29:57

标签: python python-3.x opencv numpy

我正在查看here的代码。我不能让它运行也不能与开发人员取得联系。我做了一些修改以使其工作,但我无法弄清楚为什么我收到错误:

  

TypeError:只能将整数标量数组转换为标量索引

我已打印出类型,我注意到它的类型为<class 'list'>。我试图查找各种资源但却无法理解导致问题的原因。

# applying kmeans on colwise white pixel counts
z = np.float32(a)
# Define criteria = ( type, max_iter = 10 , epsilon = 1.0 )
criteria = (cv2.TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER, 12, 0.0)
# Set flags (Just to avoid line break in the code)
flags = cv2.KMEANS_RANDOM_CENTERS
K = 5
# Apply KMeans
compactness,labels,centers = cv2.kmeans(z,K,None,criteria,10,flags)

# define colors to be used
blue = np.array([255,0,0])
green = np.array([0,255,0])
red = np.array([0,0,255])
tur = np.array([255,255,0])
purple = np.array([255,0,255])
yellow = np.array([0,255,255])

colors = [red,green,blue,purple,tur]
imcpy = np.empty_like(img)
np.copyto(imcpy,img)

# draw colors according to cluster labels
for i in range(len(a)):
        row,col = a[i][0],a[i][1]
        thisColor = colors[labels[i]]
        imcpy[row][col] = thisColor

for c in range(len(centers)):
        Crow,Ccol = centers[c][0],int(centers[c][1])
        for row in range(height):
                imcpy[row][Ccol] = np.array([255,255,255])

# characters
charHeight, charWidth = height,45
char_imgs = []
centers = sorted(centers,key=lambda x: x[1])
for c in range(len(centers)):
        Crow,Ccol = centers[c][0],int(centers[c][1])
        x1 = (Ccol-int(charWidth/2)) if ((Ccol-int(charWidth/2)) > 0) else 0
        x2 = (Ccol+int(charWidth/2)) if ((Ccol+int(charWidth/2)) < width) else width
        char_imgs.append(charcpy[0:height , x1:x2])

for x in range(len(char_imgs)):
        opPath = outDIR+"/"+ chars[x]
        if not os.path.exists(opPath):
                os.makedirs(opPath)
        cv2.imwrite(opPath +"/" + str(x) +"_" + file, char_imgs[x])

错误:

/prep# python3 prepdata.py ../images/train_120.png 
Traceback (most recent call last): File "prepdata.py", line 95, in <module> thisColor = colors[labels[i]] 
TypeError: only integer scalar arrays can be converted to a scalar index

1 个答案:

答案 0 :(得分:0)

如果您尝试使用NumPy数组索引Python列表(您的colors)(即使它只是整数),则会发生此异常:

import numpy as np

color = ['red', 'blue', 'yellow']
labels = np.array([[1, 2], [2, 3]])
color[labels[1]]
  

TypeError:只能将整数标量数组转换为标量索引

仅查看cv2.kmeans的示例,可以明确表示您应该展平(ravellabels,即:

labels = labels.ravel()