在stb_image中获取像素的RGB

#include <iostream>
#define STB_IMAGE_IMPLEMENTATION
#include "stb_image.h"

int main() {
    int width, height, channels;
    unsigned char* image_data = stbi_load("image.jpg", &width, &height, &channels, 0);
    if (image_data != nullptr) {
        // 计算像素索引
        int pixel_index = 3 * (y * width + x); // 假设要获取坐标为(x, y)的像素的RGB

        // 获取RGB值
        unsigned char r = image_data[pixel_index];
        unsigned char g = image_data[pixel_index + 1];
        unsigned char b = image_data[pixel_index + 2];

        // 输出RGB值
        std::cout << "Pixel RGB: " << static_cast<int>(r) << ", " << static_cast<int>(g) << ", " << static_cast<int>(b) << std::endl;

        // 释放图像数据
        stbi_image_free(image_data);
    } else {
        std::cout << "Failed to load image." << std::endl;
    }

    return 0;
}