固定阈值分割

深藏阁楼爱情的钟 2023-01-10 13:07 173阅读 0赞

THRESH\_BINARY:

![dst(x,y)=\\begin\{cases\}&maxval \{ if \} src(x,y)>thresh & 0 otherwise \\end\{cases\}][dst_x_y_begin_cases_maxval _ if _ src_x_y_thresh _ 0 otherwise _end_cases]

THRESH\_BINARY\_INV:

![dst(x,y)=\\begin\{cases\}&0 \{ if \} src(x,y) >thresh& maxval. otherwise \\end\{cases\}][dst_x_y_begin_cases_0 _ if _ src_x_y_ _thresh_ maxval. otherwise _end_cases]

THRESH\_TRUNC:

![dst(x,y)=\\begin\{cases\} & threshold\{ if \} src(x,y)>thresh & src(x,y) ,otherwise \\end\{cases\}][dst_x_y_begin_cases_ _ threshold_ if _ src_x_y_thresh _ src_x_y_ _otherwise _end_cases]

THRESH\_TOZERO:

![dst(x,y)=\\begin\{cases\} & src(x,y),\{ if \} src(x,y)>thresh & 0,otherwise \\end\{cases\}][dst_x_y_begin_cases_ _ src_x_y_ if _ src_x_y_thresh _ 0_otherwise _end_cases]

THRESH\_TOZERO\_INV:

![dst(x,y)=\\begin\{cases\} & 0 ,\{ if \} src(x,y)>thresh & src(x,y),otherwise \\end\{cases\}][dst_x_y_begin_cases_ _ 0 _ if _ src_x_y_thresh _ src_x_y_otherwise _end_cases]

import cv2
    import matplotlib.pyplot as plt
    img = cv2.imread('test3.jpg',0)
    ret,thresh1 = cv2.threshold(img,127,255,cv2.THRESH_BINARY)
    ret,thresh2 = cv2.threshold(img,127,255,cv2.THRESH_BINARY_INV)
    ret,thresh3 = cv2.threshold(img,127,255,cv2.THRESH_TRUNC)
    ret,thresh4 = cv2.threshold(img,127,255,cv2.THRESH_TOZERO)
    ret,thresh5 = cv2.threshold(img,127,255,cv2.THRESH_TOZERO_INV)
    images = [img,thresh1,thresh2,thresh3,thresh4,thresh5]
    for i in range(6):
        plt.subplot(2,3,i+1)
        plt.imshow(images[i],cmap='gray')
        plt.xticks([])
        plt.yticks([])
    plt.suptitle('fixed threshold')
    plt.show()

运行结果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dpbmdneW4_size_16_color_FFFFFF_t_70][]

使用到的test3.jpg:

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dpbmdneW4_size_16_color_FFFFFF_t_70 1][]

[dst_x_y_begin_cases_maxval _ if _ src_x_y_thresh _ 0 otherwise _end_cases]: https://private.codecogs.com/gif.latex?%5Cinline%20%5Cfn_cm%20dst%28x%2Cy%29%3D%5Cbegin%7Bcases%7D%26maxval%20%7B%20if%20%7D%20src%28x%2Cy%29%3Ethresh%20%26%200%20otherwise%20%5Cend%7Bcases%7D
[dst_x_y_begin_cases_0 _ if _ src_x_y_ _thresh_ maxval. otherwise _end_cases]: https://private.codecogs.com/gif.latex?%5Cinline%20%5Cfn_cm%20dst%28x%2Cy%29%3D%5Cbegin%7Bcases%7D%260%20%7B%20if%20%7D%20src%28x%2Cy%29%20%3Ethresh%26%20maxval.%20otherwise%20%5Cend%7Bcases%7D
[dst_x_y_begin_cases_ _ threshold_ if _ src_x_y_thresh _ src_x_y_ _otherwise _end_cases]: https://private.codecogs.com/gif.latex?%5Cinline%20%5Cfn_cm%20dst%28x%2Cy%29%3D%5Cbegin%7Bcases%7D%20%26%20threshold%7B%20if%20%7D%20src%28x%2Cy%29%3Ethresh%20%26%20src%28x%2Cy%29%20%2Cotherwise%20%5Cend%7Bcases%7D
[dst_x_y_begin_cases_ _ src_x_y_ if _ src_x_y_thresh _ 0_otherwise _end_cases]: https://private.codecogs.com/gif.latex?%5Cinline%20%5Cfn_cm%20dst%28x%2Cy%29%3D%5Cbegin%7Bcases%7D%20%26%20src%28x%2Cy%29%2C%7B%20if%20%7D%20src%28x%2Cy%29%3Ethresh%20%26%200%2Cotherwise%20%5Cend%7Bcases%7D
[dst_x_y_begin_cases_ _ 0 _ if _ src_x_y_thresh _ src_x_y_otherwise _end_cases]: https://private.codecogs.com/gif.latex?%5Cinline%20%5Cfn_cm%20dst%28x%2Cy%29%3D%5Cbegin%7Bcases%7D%20%26%200%20%2C%7B%20if%20%7D%20src%28x%2Cy%29%3Ethresh%20%26%20src%28x%2Cy%29%2Cotherwise%20%5Cend%7Bcases%7D
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dpbmdneW4_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20210124115924694.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dpbmdneW4=,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dpbmdneW4_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20210124120001720.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dpbmdneW4=,size_16,color_FFFFFF,t_70