大津法找阈值c语言代码

下面是使用C语言实现大津法找阈值的示例代码：

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int otsuThreshold(int hist[], int total) {
    int sum = 0;
    for (int i = 0; i < 256; ++i) {
        sum += i * hist[i];
    }

    int sumB = 0;
    int wB = 0;
    int wF = 0;

    int threshold = 0;
    double maxVarBetween = 0.0;

    for (int i = 0; i < 256; ++i) {
        wB += hist[i];
        if (wB == 0)
            continue;

        wF = total - wB;
        if (wF == 0)
            break;

        sumB += i * hist[i];

        double meanB = (double)sumB / wB;
        double meanF = (double)(sum - sumB) / wF;

        double varBetween = (double)wB * (double)wF * pow((meanB - meanF), 2);

        if (varBetween > maxVarBetween) {
            maxVarBetween = varBetween;
            threshold = i;
        }
    }

    return threshold;
}

int main() {
    int hist[256] = {0}; // 像素灰度级别的直方图
    int total = 0; // 像素总数

    // TODO: 读取图像并计算直方图

    // 示例直方图数据
    hist[0] = 10;
    hist[100] = 50;
    hist[150] = 100;
    total = 160;

    int threshold = otsuThreshold(hist, total);
    printf("Otsu threshold: %d\n", threshold);

    return 0;
}

以上代码是一个简单的示例，其中直方图数据使用固定的值，实际应用中需要读取图像并计算直方图。你可以根据自己的需求进行修改和扩展。在运行时，它将输出计算得到的阈值。