The basic principle of image reversal (basic gradation conversion function) and implemented in Python

1. Basic principles

Obtaining pixel values [0, L] reversed image of the image range, that is negative. Suitable for enhanced image in white or gray areas , especially when the black occupy the main position in the picture when

$$T(r) = L-r$$

2. Run results

FIG derived skimage

3. Code

 1 import numpy as np
 2 
 3 def image_reverse(input_image):
 4     '''
 5     图像反转
 6     :param input_image: 原图像
 7     :return: 反转后的图像
 8     '''
 9     input_image_cp = np.copy(input_image) # 输入图像的副本
10 
11     pixels_value_max = np.max(input_image_cp) # 输入图像像素的最大值
12 
13     output_imgae = pixels_value_max - input_image_cp # 输出图像
14 
15     return output_imgae