现在虚拟视点生成了yuv格式的视频流，如何计算每一帧的psnr值，进行了如下步骤：
1.对yuv视频流进行转换为jpg图片；
2.把jpg图片转化为avi视频流，便于批处理；
3.对avi视频中的每一帧计算psnr值。
程序：
[cpp] view plain copy #include <stdlib.h> #include <stdio.h> #include <math.h> #include <cv.h> #include <highgui.h> #define NUM_FRAME 100 //只处理前100帧，根据视频帧数可修改 void CalcPsnr(const char *in1,const char *in2) { cv::VideoCapture vc1; cv::VideoCapture vc2; bool flag1 = vc1.open(in1); bool flag2 = vc2.open(in2); if (!flag1||!flag2) { printf("avi file open error \n"); system("pause"); exit(-1); } int frmCount1 = vc1.get(CV_CAP_PROP_FRAME_COUNT); int frmCount2 = vc2.get(CV_CAP_PROP_FRAME_COUNT); printf("frmCount: %d \n", frmCount1); printf("frmCount: %d \n", frmCount2); for (int i = 0; i < frmCount1; i++) { printf("%d/%d \n", i + 1, frmCount1); cv::Mat image_ref; vc1 >> image_ref; cv::Mat image_obj; vc2 >> image_obj; double mse = 0; double div_r = 0; double div_g = 0; double div_b = 0; int width = image_ref.cols; int height = image_ref.rows; double psnr = 0; for (int v = 0; v < height; v++) { for (int u = 0; u < width; u++) { div_r = image_ref.at<cv::Vec3b>(v, u)[0] - image_obj.at<cv::Vec3b>(v, u)[0]; div_g = image_ref.at<cv::Vec3b>(v, u)[1] - image_obj.at<cv::Vec3b>(v, u)[1]; div_b = image_ref.at<cv::Vec3b>(v, u)[2] - image_obj.at<cv::Vec3b>(v, u)[2]; mse += ((div_r*div_r + div_b*div_b + div_g*div_g) / 3); } } mse = mse / (width*height); psnr = 10 * log10(255 * 255 / mse); printf("%lf\n", mse); printf("%lf\n", psnr); } return; } void DisplayYUV2RGB(const char *dir,const char *in,int _w,int _h) { int w = _w; int h = _h; printf("yuv file w: %d, h: %d \n", w, h); FILE* pFileIn = fopen(in, "rb+"); int bufLen = w*h * 3 / 2; unsigned char* pYuvBuf = new unsigned char[bufLen]; int iCount = 0; for (int i = 0; i<NUM_FRAME; i++) { fread(pYuvBuf, bufLen*sizeof(unsigned char), 1, pFileIn); cv::Mat yuvImg; yuvImg.create(h * 3 / 2, w, CV_8UC1); memcpy(yuvImg.data, pYuvBuf, bufLen*sizeof(unsigned char)); cv::Mat rgbImg; cv::cvtColor(yuvImg, rgbImg, CV_YUV2BGR_I420); cv::imshow("img", rgbImg); char s[100]; sprintf(s,"%spic%d%s",dir,i,".jpg"); cv::imwrite(s, rgbImg); cv::waitKey(1); printf("%d \n", iCount++); } delete[] pYuvBuf; fclose(pFileIn); } void Image_to_video(const char* in, const char* out) { int num = 1; CvSize size = cvSize(1024, 768); //视频帧格式的大小 double fps = 30; //每秒钟的帧率 CvVideoWriter *writer = cvCreateVideoWriter(out, CV_FOURCC('D', 'I', 'V', 'X'), fps, size); //创建视频文件 char cname[100]; sprintf(cname, in, num); //加载图片的文件夹，图片的名称编号是1开始1，2,3,4,5.。。。 IplImage *src = cvLoadImage(cname); if (!src) { return; } IplImage *src_resize = cvCreateImage(size, 8, 3); //创建视频文件格式大小的图片 cvNamedWindow("avi"); while (src) { cvShowImage("avi", src_resize); cvWaitKey(1); cvResize(src, src_resize); //将读取的图片设置为视频格式大小相同 cvWriteFrame(writer, src_resize); //保存图片为视频流格式 cvReleaseImage(&src); //释放空间 num++; sprintf(cname, in, num); src = cvLoadImage(cname); //循环读取数据 } cvReleaseVideoWriter(&writer); cvReleaseImage(&src_resize); } int main(int argc, char *argv[]) { const char *out = "C:/Users/jiang/Desktop/output/book_virtual08.yuv"; const char *dir = "C:/Users/jiang/Desktop/output/tupian1/"; DisplayYUV2RGB(dir, out, 1024, 768); const char *outImagename = "C:/Users/jiang/Desktop/output/tupian1/pic%d.jpg"; const char *outVideoname = "C:/Users/jiang/Desktop/output/3outfile.avi"; Image_to_video(outImagename, outVideoname); out = "C:/Users/jiang/Desktop/bookarrival/bookarrival_c_8.yuv"; dir = "C:/Users/jiang/Desktop/output/tupian1/"; DisplayYUV2RGB(dir, out, 1024, 768); outImagename = "C:/Users/jiang/Desktop/output/tupian1/pic%d.jpg"; outVideoname = "C:/Users/jiang/Desktop/output/4outfile.avi"; Image_to_video(outImagename, outVideoname); const char *in1 = "C:/Users/jiang/Desktop/output/3outfile.avi"; const char *in2 = "C:/Users/jiang/Desktop/output/4outfile.avi"; CalcPsnr(in1, in2); getchar(); } 文章标签： 视频流 批处理 视频 psnr 个人分类： 虚拟视点