使用 python 从图像中提取颜色

Question

我有一张黑白图像和一张带有彩色笔触的图像。我想要做的是提取颜色笔划，模糊它们，然后将原始图像与模糊图像混合。我通过将两个图像彼此相减来提取颜色笔划，但我在黑色背景上得到这些颜色笔划，而我需要它们在白色上与原始图像混合。这是我的代码的一部分：

def imageblur(cimg):
    return cv2.blur(cimg, (50, 50))


bw = glob('path1')
colorful = glob('path2')
output_dir = 'path3'
index = 0


for i,j in zip(bw, colorful):
    img1 = cv2.imread(i)
    img2 = cv2.imread(j)
    color = cv2.subtract(img1,img2)
    color = imageblur(color)
    mask = Image.fromarray(np.uint8(color))
    img = Image.fromarray(np.uint8(img1))
    im = Image.blend(img, mask, 0.5)
    #color = img1 + color
    im.save(os.path.join(output_dir, str(index) + '.jpg'))
    index += 1
    print(index)

样本images

Answer 1

如果您想将 RGB 图像的背景从黑色更改为白色，您可以这样做：

#thresholds all black color in your "color-on-black-background" image 
#to maximum value (255,255,255) (white) and sets the rest (yours colors) 
#to (0,0,0) (black)
thresholded=cv2.inRange(img,(0,0,0),(0,0,0))
#add both images
res=img+cv2.cvtColor(thresholded,cv2.COLOR_GRAY2BGR)

输入（图片）：

阈值（阈值）：

输出（分辨率）：

Answer 2

使用样本图像得到结果。处理略有改动。

import numpy as np
import cv2
import matplotlib.pyplot as plt
%matplotlib inline 

def show(title, img, color=True):
    if color:
        plt.imshow(img[:,:,::-1]), plt.title(title), plt.show()
    else:
        plt.imshow(img, cmap='gray'), plt.title(title), plt.show()

img = cv2.imread('color_strokes.jpg')
show('original', img)

mask=cv2.inRange(img,(0,0,0),(150,150,150))
show('mask', mask, False)

res=255-cv2.cvtColor(mask,cv2.COLOR_GRAY2BGR)
show('result', res, False)

输出：

Answer 3

image = plt.imread('image.jpg')

# Extract 2-D arrays of the RGB channels: red, blue, green
red, blue, green = image[:,:,0], image[:,:,1], image[:,:,2]

Answer 4

从图像中提取颜色：

import colorgram

# It is the number of colors you want to extract from the image
nb_colors = 30      

# Returns a list of tuples form (r, g, b) 
image_colors = colorgram.extract("image.jpg", nb_colors)

使用 python 从图像中提取颜色

Extract colors from image using python

python

opencv

image

image-processing

python-imaging-library