OpenCV访问当前帧和上一帧 我需要OpenCV C++中的一些计算的当前和先前的框架。

以下是我目前的代码：

    vector <cv::Mat> frames;
    // Current frame
    Mat M = current_frame; 
    Mat F; // previous frame
    // set Previous Frame
    if (frames.empty()) {
        F = M;
        frames.push_back(M);
        cout << "empty" << endl;
    }
    else {
        F = frames.back();
        frames.push_back(M);
        cout << " NOTempty" << endl;
    }

    // print frame Mat means to see if things look okay
    cout << mean(M) << endl;
    cout << mean(F) << endl;

应该是这样的：

empty
[5.09352, 6.60551, 8.54364, 0]
[5.09352, 6.60551, 8.54364, 0]

 NOTempty
[5.02325, 6.46646, 8.39534, 0]
[5.09352, 6.60551, 8.54364, 0]

 NOTempty
[4.94272, 6.38162, 8.32141, 0]
[5.02325, 6.46646, 8.39534, 0]

//create a dummy vector of mats:
std::vector<cv::Mat> sourceMats;
sourceMats.push_back( cv::Mat(1, 4, CV_32F, {1, 1, 1, 1}) );
sourceMats.push_back( cv::Mat(1, 4, CV_32F, {2, 2, 2, 2}) );
sourceMats.push_back( cv::Mat(1, 4, CV_32F, {3, 3, 3, 3}) );

//frames buffer:
std::vector <cv::Mat> frames;

//loop thru all frames:
for( int i = 0; i < (int)sourceMats.size(); i++ ){

    // Current frame
    cv::Mat M = sourceMats[i];
    cv::Mat F; // previous frame

    // set Previous Frame
    if (frames.empty()) {
        F = M;
        frames.push_back(M);
        std::cout << "empty" << std::endl;
    }
    else {
        F = frames.back();
        frames.push_back(M);
        std::cout << " NOTempty" << std::endl;
    }

    // do not compute the mean, I just want to check out the FIFO contents:
    std::cout << M << std::endl;
    std::cout << F << std::endl;
}

---

这应该很简单，我做错了什么？

您确定该代码段中没有遗漏循环吗？如果我尝试这样的方法：

empty
[5.09352, 6.60551, 8.54364, 0]
[5.09352, 6.60551, 8.54364, 0]

 NOTempty
[5.02325, 6.46646, 8.39534, 0]
[5.09352, 6.60551, 8.54364, 0]

 NOTempty
[4.94272, 6.38162, 8.32141, 0]
[5.02325, 6.46646, 8.39534, 0]

//create a dummy vector of mats:
std::vector<cv::Mat> sourceMats;
sourceMats.push_back( cv::Mat(1, 4, CV_32F, {1, 1, 1, 1}) );
sourceMats.push_back( cv::Mat(1, 4, CV_32F, {2, 2, 2, 2}) );
sourceMats.push_back( cv::Mat(1, 4, CV_32F, {3, 3, 3, 3}) );

//frames buffer:
std::vector <cv::Mat> frames;

//loop thru all frames:
for( int i = 0; i < (int)sourceMats.size(); i++ ){

    // Current frame
    cv::Mat M = sourceMats[i];
    cv::Mat F; // previous frame

    // set Previous Frame
    if (frames.empty()) {
        F = M;
        frames.push_back(M);
        std::cout << "empty" << std::endl;
    }
    else {
        F = frames.back();
        frames.push_back(M);
        std::cout << " NOTempty" << std::endl;
    }

    // do not compute the mean, I just want to check out the FIFO contents:
    std::cout << M << std::endl;
    std::cout << F << std::endl;
}

---

似乎您的

FIFO

正在按预期工作。。。您对函数的期望是什么？

为什么还要使用向量呢。您只需要两个变量，用于前一帧和当前帧。每当出现新帧时，分配

previous\u frame=current\u frame；当前_帧=新_帧并检查
是否（上一个_frame.empty（）| |当前_frame.empty（））继续还是什么