求助大神，论文里这种ostu的改进方法要怎么写怎么复现？！！！

[IreneTa]

ostu源码，要改阈值选择规则...

from PIL import Image

im = Image.open('maize.jpg')
im = im.convert('L')
width, height = im.size
# img_pix;图像像素数
img_pix=width*height
pix = im.load()
#直方图hist
hist=im.histogram()
#img_gray;图像灰度和
img_gray=0;
for i in range(256):
    img_gray +=i*hist[i];
# img_avg_gray;图像平均灰度
img_avg_gray=img_gray/img_pix;
front_pix=0;# front_pix;前景像素数
front_sum_gray=0;# front_sum_gray;前景灰度和
temp=0;
Th=0;
for t in range(256):

    front_pix +=hist[t];
    front_pix_per=front_pix/img_pix;# front_pix_per;前景像素占比
    bg_pix=img_pix-front_pix;# bg_pix;背景像素数
    bg_pix_per=bg_pix/img_pix;# bg_pix_per;背景像素占比
    if front_pix == 0:
        continue;
    if bg_pix==0:
        break;
    front_sum_gray +=hist[t]*t;
    front_avg_gray=front_sum_gray/front_pix;# front_ave_gray;前景像素平均灰度
    bg_sum_gray=img_gray-front_sum_gray;# bg_sum_gray;背景像素灰度和
    bg_avg_gray = bg_sum_gray/bg_pix;# bg_avg_gray;背景像素平均灰度

    g=front_pix_per*bg_pix_per*(front_avg_gray-bg_avg_gray)*(front_avg_gray-bg_avg_gray)
    # g;类间方差
    # g = front_pix_per * (front_avg_gray - img_avg_gray)*(front_avg_gray - img_avg_gray)+
    #  bg_pix_per* (bg_avg_gray - img_avg_gray)*(bg_avg_gray - img_avg_gray)
    if g >=temp:
        temp = g;
        Th = t;
for w in range(width):
    for h in range(height):
        if pix[w,h]>Th:
            pix[w,h]=255;
        if pix[w,h]<=Th:
            pix[w,h]=0;
im.show();