下面是Linux 大津法二值化的C语言代码，图片的格式为320*240。
typedef struct hand_pic {
int iWidth; /* 宽度: 一行有多少个象素 */
int iHeight; /* 高度: 一列有多少个象素 */
int iTotalBytes; /* 所有字节数 */
int iBpp;
int centre_x;
int centre_y;
int last_grade;
int same_grade_count;
unsigned char *green_pix; //图像的灰度值
}T_hand_pic, *PT_hand_pic;
/*******************************************
* 函数名称： otsu_method
* 功能描述： 大津法二值化图像
* 输入参数： PT_hand_pic - 一个结构体,包涵处理图片的主要参数
* 输出参数：
* 返 回 值： 0 - 成功, 负数 - 失败
/*******************************************/
static int otsu_method(PT_hand_pic ptHandPic)
{
unsigned int max,min;
int x,y;
unsigned int color;
unsigned char *greed_pix=ptHandPic->green_pix;
unsigned int *count;
double probability[330]={0};
double sum_probability;
max=min=*greed_pix;
for (y = 0; y < ptHandPic->iHeight; y++){//get mix & min
for (x = 0; x < ptHandPic->iWidth; x++){
color = *(greed_pix+x+y * ptHandPic->iWidth);
if(color > max)
max = color;
if(color < min)
min = color;
}
}
count=(unsigned int *)calloc(max-min+1,sizeof(int));
for (y = 0; y < ptHandPic->iHeight; y++){
for (x = 0; x < ptHandPic->iWidth; x++){
color = *(greed_pix+x+y* ptHandPic->iWidth);
*(count+color-min) +=1;
}
}
y= ptHandPic->iWidth * ptHandPic->iHeight;
for (x = 0; x <max-min+1; x++){
*(probability+x) = (double)*(count+x)*100/(double)y;
}
sum_probability=0;
//for (x = 0; x <max-min+1; x++){
// sum_probability += *(probability+x) * (double)(*(count+x));
//}
for (x = min,y=0; x <max+1; x++,y++){
//printf("myyyyyyy :%d \n" ,y );
sum_probability += *(probability+y) *(double)x;
}
sum_probability = sum_probability/100;
// printf("hhhh%f",sum_probability);
if(ptHandPic->iBpp==32)
if((sum_probability<60)||(sum_probability>190)){
free(count);
return -1;
}
//printf("here sum_probability %f\n" ,sum_probability);
//binaryzation
for (y = 0; y < ptHandPic->iHeight; y++){
for (x = 0; x < ptHandPic->iWidth; x++){
if (*(greed_pix+x+y* ptHandPic->iWidth) >= sum_probability )
*(greed_pix+x+y* ptHandPic->iWidth)=1;
else
*(greed_pix+x+y* ptHandPic->iWidth)=0;
}
}
free(count);
return 0;
}