OpenCV C++实现Lucas-Kanade光流：Python转译轨迹绘制问题

作为OpenCV和Python的新手，我正在做一个小项目——给视频里的多个运动物体绘制轨迹，最终输出包含物体最终状态和轨迹的图像。我参考了OpenCV官方的Lucas-Kanade光流示例，折腾了好一阵把Python代码的第一部分转成了C++，但到轨迹绘制的环节就卡壳了。

以下是我已经完成的C++代码：

#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/video/tracking.hpp"
#include "opencv2/imgproc.hpp"
#include <iostream>
using namespace cv;
using namespace std;
/**
 * @function main
 */
int main(int argc, char** argv) {
 //TODO
 VideoCapture src = VideoCapture("C:\\Users\\youss\\Desktop\\opencv\\movingCars.mp4");
 Mat currentFrame, oldGrayedFrame, grayedFrame, mask ;
 vector<Point2f> prevPts, nextPts;
 vector<uchar> status;
 vector<float> err;
 vector<Point2f> corners;
 Mat good_new = Mat(), good_old = Mat();
 int maxCorners = 100, minDistance = 7, blockSize = 7;
 double qualityLevel = 0.3;
 src.read(currentFrame);
 cvtColor(currentFrame, oldGrayedFrame, COLOR_BGR2GRAY);
 goodFeaturesToTrack(oldGrayedFrame, corners, maxCorners, qualityLevel, minDistance, Mat(), blockSize);
 mask = Mat::zeros(currentFrame.size(), currentFrame.type());
 prevPts = corners;
 //while (true) {
 src.read(currentFrame);
 cvtColor(currentFrame, grayedFrame, COLOR_BGR2GRAY);
 calcOpticalFlowPyrLK(oldGrayedFrame, grayedFrame, prevPts, nextPts, status, err);
 int i, k;
 for (i = k = 0; i < nextPts.size(); i++) {
 if (!status[i]) continue;
 prevPts[k] = prevPts[i];
 nextPts[k] = nextPts[i];
 err[k] = err[i];
 k++;
 }
 prevPts.resize(k);
 nextPts.resize(k);
 err.resize(k);
 //}
}

我并不希望大家直接帮我写完代码，只想要一些思路或者提示，帮我把下面这段Python的轨迹绘制代码转译成C++：

# draw the tracks
for i,(new,old) in enumerate(zip(good_new,good_old)):
 a,b = new.ravel()
 c,d = old.ravel()
 mask = cv2.line(mask, (a,b),(c,d), color[i].tolist(), 2)
 frame = cv2.circle(frame,(a,b),5,color[i].tolist(),-1)
 img = cv2.add(frame,mask)

内容的提问来源于stack exchange，提问作者hereForLearing