opencv::证件照背景替换

证件照背景替换
    K-Means
    背景融合 – 高斯模糊
    遮罩层生成 

#include <opencv2/opencv.hpp>
#include <iostream>

using namespace cv;
using namespace std;

Mat mat_to_samples(Mat &image);
int main(int argc, char** argv) {
    Mat src = imread("D:/images/toux.jpg");
    if (src.empty()) {
        printf("could not load image...\n");
        return -;
    }
    namedWindow("input image", CV_WINDOW_AUTOSIZE);
    imshow("input image", src);

    // 组装数据
    Mat points = mat_to_samples(src);

    // 运行KMeans
    int numCluster = ;
    Mat labels;
    Mat centers;
    TermCriteria criteria = TermCriteria(TermCriteria::EPS + TermCriteria::COUNT, , 0.1);
    kmeans(points, numCluster, labels, criteria, , KMEANS_PP_CENTERS, centers);

    // 去背景+遮罩生成
    Mat mask = Mat::zeros(src.size(), CV_8UC1);
    int index = src.rows *  + ;
    int cindex = labels.at<int>(index, );
    int height = src.rows;
    int width = src.cols;
    //bian
    for (int row = ; row < height; row++) {
        for (int col = ; col < width; col++) {
            index = row * width + col;
            int label = labels.at<int>(index, );
            if (label == cindex) { // 背景
                mask.at<uchar>(row, col) = ;
            }
            else {
                mask.at<uchar>(row, col) = ;
            }
        }
    }
    //imshow("mask", mask);

    // 腐蚀 + 高斯模糊
    Mat k = getStructuringElement(MORPH_RECT, Size(, ), Point(-, -));
    erode(mask, mask, k);
    //imshow("erode-mask", mask);
    GaussianBlur(mask, mask, Size(, ), , );
    //imshow("Blur Mask", mask);

    // 通道混合
    RNG rng();
    Vec3b color;
    color[] = ; // rng.uniform(0, 255);
    color[] = ;  // rng.uniform(0, 255);
    color[] = ; // rng.uniform(0, 255);
    Mat result(src.size(), src.type());

    double w = 0.0;
    int b = ,  g = ,  r = ;
    int b1 = , g1 = , r1 = ;
    int b2 = , g2 = , r2 = ;

    for (int row = ; row < height; row++) {
        for (int col = ; col < width; col++) {
            int m = mask.at<uchar>(row, col);
            if (m == ) {
                result.at<Vec3b>(row, col) = src.at<Vec3b>(row, col); // 前景
            }
            else if (m == ) {
                result.at<Vec3b>(row, col) = color; // 背景
            }
            else {
                //权重
                w = m / 255.0;
                b1 = src.at<Vec3b>(row, col)[];
                g1 = src.at<Vec3b>(row, col)[];
                r1 = src.at<Vec3b>(row, col)[];

                b2 = color[];
                g2 = color[];
                r2 = color[];

                b = b1 * w + b2 * (1.0 - w);
                g = g1 * w + g2 * (1.0 - w);
                r = r1 * w + r2 * (1.0 - w);

                result.at<Vec3b>(row, col)[] = b;
                result.at<Vec3b>(row, col)[] = g;
                result.at<Vec3b>(row, col)[] = r;
            }
        }
    }
    imshow("背景替换", result);

    waitKey();
    return ;
}

Mat mat_to_samples(Mat &image) {
    int w = image.cols;
    int h = image.rows;
    int samplecount = w * h;
    int dims = image.channels();
    Mat points(samplecount, dims, CV_32F, Scalar());

    int index = ;
    for (int row = ; row < h; row++) {
        for (int col = ; col < w; col++) {
            index = row * w + col;
            Vec3b bgr = image.at<Vec3b>(row, col);
            points.at<float>(index, ) = static_cast<int>(bgr[]);
            points.at<float>(index, ) = static_cast<int>(bgr[]);
            points.at<float>(index, ) = static_cast<int>(bgr[]);
        }
    }
    return points;
}