PQCVMedia/src/opencv/image_fingerprint.cpp

//
// Created by 阳坤 on 2022/3/2.
//


#include "image_fingerprint.h"


//AVFrame 转 cv::mat
cv::Mat avframeToCvmat(const AVFrame *frame) {
    int width = frame->width;
    int height = frame->height;
    cv::Mat image(height, width, CV_8UC3);
    int cvLinesizes[1];
    cvLinesizes[0] = image.step1();
    SwsContext *conversion = sws_getContext(width, height, (AVPixelFormat) frame->format, width, height,
                                            AVPixelFormat::AV_PIX_FMT_BGR24, SWS_FAST_BILINEAR, NULL, NULL, NULL);
    sws_scale(conversion, frame->data, frame->linesize, 0, height, &image.data, cvLinesizes);
    sws_freeContext(conversion);
    return image;
}

//cv::Mat 转 AVFrame
AVFrame *cvmatToAvframe(cv::Mat *image, AVFrame *frame) {
    int width = image->cols;
    int height = image->rows;
    int cvLinesizes[1];
    cvLinesizes[0] = image->step1();
    if (frame == NULL) {
        frame = av_frame_alloc();
        av_image_alloc(frame->data, frame->linesize, width, height, AVPixelFormat::AV_PIX_FMT_YUV420P, 1);
    }
    SwsContext *conversion = sws_getContext(width, height, AVPixelFormat::AV_PIX_FMT_BGR24, width, height,
                                            (AVPixelFormat) frame->format, SWS_FAST_BILINEAR, NULL, NULL, NULL);
    sws_scale(conversion, &image->data, cvLinesizes, 0, height, frame->data, frame->linesize);
    sws_freeContext(conversion);
    return frame;
}

int fingerprintFromFFAVFrame(FILE *file, AVFrame *frame, char buf[64]) {
    if (file) fprintf(file, "fingerprintFromFFAVFrame\n");
    if (!frame)return NULL;

//    if (1) {
//        memset((void *)buf, 0,sizeof(char) * 8 * 8);
//        for (int i = 0; i <64 ; ++i) {
//            buf[i] = 1;
//        }
//        return 64;
//    }

//    auto img = avframeToCvmat(frame);
    int width = frame->width;
    int height = frame->height;
    cv::Mat img(height, width, CV_8UC3);
    int cvLinesizes[1];
    cvLinesizes[0] = img.step1();
    SwsContext *conversion = sws_getContext(width, height, (AVPixelFormat) frame->format, width, height,
                                            AVPixelFormat::AV_PIX_FMT_BGR24, SWS_FAST_BILINEAR, NULL, NULL, NULL);
    sws_scale(conversion, frame->data, frame->linesize, 0, height, &img.data, cvLinesizes);
    sws_freeContext(conversion);
    if (img.empty()) {
        printf("image is empty.");
        return NULL;
    }
    if (file) fprintf(file, "fingerprintFromFFAVFrame 2\n");
//    std::string str = frame->pts + "";
//    imshow(str, img);
    int scale_width = 8, scale_height = 8;
    Mat gray, res;
    if (file) fprintf(file, "fingerprintFromFFAVFrame 3\n");
    //缩放成8x8大小灰度图
    resize(img, res, Size(scale_width, scale_height));
    if (file) fprintf(file, "fingerprintFromFFAVFrame 4\n");
    cvtColor(res, gray, COLOR_BGR2GRAY);
    if (file) fprintf(file, "fingerprintFromFFAVFrame 5\n");
    Mat mat_mean, mat_stddev;
    meanStdDev(gray, mat_mean, mat_stddev);//求灰度图像的均值、均方差
    double mn = 0;
    if (!mat_mean.empty()) {
        mn = mat_mean.at<double>(0, 0);
    } else {
        printf("灰度平均值 empty！\n");
        return -1;
    };
    //获取灰度平均值
//     mn = mean(gray)[0];
    if (file) fprintf(file, "fingerprintFromFFAVFrame 6\n");
    if (file) fprintf(file, "fingerprintFromFFAVFrame 7\n");
    if (gray.cols * gray.rows < scale_height * scale_width)return NULL;
//    //得到图像指纹值
    for (int i = 0; i < 8; i++) {
        for (int j = 0; j < 8; j++) {
            buf[i * 8 + j] = (gray.at<unsigned char>(i, j) > mn) ? 1 : 0;
        }
    }
    if (file) fprintf(file, "fingerprintFromFFAVFrame 8\n");
    if (file) fprintf(file, "fingerprintFromFFAVFrame 9\n");
    return scale_width * scale_height;
}

float fingerprint_compare(const char *arr, const char *arr2, int len) {
    int size = len;
    int sim_sum = 0;
    for (int i = 0; i < size; ++i) {
        if (arr[i] == arr2[i])
            sim_sum++;
    }
    return sim_sum * 1.0 / size;
}