struck（结构化SVM用于视觉跟踪）--源代码详解--main.cpp

struck 利用结构化SVM来实现视觉跟踪，在深度学习流行起来之前，struck是视觉跟踪领域效果最好的方法。深度学习流行之后，利用泛化的卷积特征能够得到很好的效果。struck的优点在于，它可以使用任意的特征来实现跟踪，因此它可以利用卷积神经网络提取的特征，然后结合结构化SVM来实现视觉跟踪，这样的效果说不定更好。

struck的源码是C++实现的，作者写的很好，思路清晰，代码结构清晰，而且与论文中的相符，没有那么多小trick，结果比较可靠。

下面从它的主函数开始，分析这份源码是如何实现的：

main.cpp

/*  * Struck: Structured Output Tracking with Kernels *  * Code to accompany the paper: *   Struck: Structured Output Tracking with Kernels *   Sam Hare, Amir Saffari, Philip H. S. Torr *   International Conference on Computer Vision (ICCV), 2011 *  * Copyright (C) 2011 Sam Hare, Oxford Brookes University, Oxford, UK *  * This file is part of Struck. *  * Struck is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. *  * Struck is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. *  * You should have received a copy of the GNU General Public License * along with Struck.  If not, see <http://www.gnu.org/licenses/>. *  */ #include "Tracker.h"#include "Config.h"#include <iostream>#include <fstream>#include <opencv/cv.h>#include <opencv/highgui.h>using namespace std;using namespace cv;static const int kLiveBoxWidth = 80;static const int kLiveBoxHeight = 80;void rectangle(Mat& rMat, const FloatRect& rRect, const Scalar& rColour){IntRect r(rRect);rectangle(rMat, Point(r.XMin(), r.YMin()), Point(r.XMax(), r.YMax()), rColour);}int main(int argc, char* argv[]){//这几句话没啥作用，我给注释掉#ifndef WIN32string programName = argv[0];programName = programName.substr(programName.find_first_of('/'));cout << "programName: " << programName << endl;#endif// read config filestring configPath = "../docs/config.txt";Config conf(configPath);//作者定义的类Config 读取了所有的配置信息，并且cout输出cout << conf << endl;if (conf.features.size() == 0){cout << "error: no features specified in config" << endl;return EXIT_FAILURE;}if (argc > 1){conf.sequenceName = argv[1];}ofstream outFile;//定义一个输出文件流，输出结果if (conf.resultsPath != ""){#ifdef WIN32string resultsPath = conf.resultsPath + "/" + conf.sequenceName + "_result.txt";#elsestring resultsPath = conf.resultsPath + "/" + conf.sequenceName + "_" + programName + "Result.txt";#endifoutFile.open(resultsPath, ios::out);if (!outFile){cout << "error: could not open results file: " << conf.resultsPath << endl;return EXIT_FAILURE;}}// if no sequence specified then use the camerabool useCamera = (conf.sequenceName == "");//根据在config.txt中是否给出视频名称，判断是否使用摄像头VideoCapture cap;int startFrame = -1;int endFrame = -1;FloatRect initBB;//这是一个模板类，string imgFormat;float scaleW = 1.f;float scaleH = 1.f;if (useCamera)//使用摄像头{if (!cap.open(0)){cout << "error: could not start camera capture" << endl;return EXIT_FAILURE;}startFrame = 0;endFrame = INT_MAX;Mat tmp;cap >> tmp;//读入一帧视频scaleW = (float)conf.frameWidth/tmp.cols;//config中宽/读入视频的宽，比率scaleH = (float)conf.frameHeight/tmp.rows;/*该函数，创造了一个矩形，左上角在（120,80）,80*80的矩形*/initBB = IntRect(conf.frameWidth/2-kLiveBoxWidth/2, conf.frameHeight/2-kLiveBoxHeight/2, kLiveBoxWidth, kLiveBoxHeight);cout << "press 'i' to initialise tracker" << endl;}else//使用视频{// parse frames filestring framesFilePath = conf.sequenceBasePath+"/"+conf.sequenceName+"/"+"frames.txt";ifstream framesFile(framesFilePath.c_str(), ios::in);if (!framesFile){cout << "error: could not open sequence frames file: " << framesFilePath << endl;return EXIT_FAILURE;}string framesLine;getline(framesFile, framesLine);printf("%s", framesLine.c_str());sscanf(framesLine.c_str(), "%d,%d", &startFrame, &endFrame);if (framesFile.fail() || startFrame == -1 || endFrame == -1){cout << "error: could not parse sequence frames file" << endl;return EXIT_FAILURE;}imgFormat = conf.sequenceBasePath+"/"+conf.sequenceName+"/img/%04d.jpg";//qyy changed// read first frame to get sizechar imgPath[256];sprintf(imgPath, imgFormat.c_str(), startFrame);Mat tmp = cv::imread(imgPath, 0);scaleW = (float)conf.frameWidth/tmp.cols;scaleH = (float)conf.frameHeight/tmp.rows;// read init box from ground truth filestring gtFilePath = conf.sequenceBasePath+"/"+conf.sequenceName+"/"+"groundtruth_rect.txt";//qyy changedifstream gtFile(gtFilePath.c_str(), ios::in);if (!gtFile){cout << "error: could not open sequence gt file: " << gtFilePath << endl;return EXIT_FAILURE;}string gtLine;getline(gtFile, gtLine);float xmin = -1.f;float ymin = -1.f;float width = -1.f;float height = -1.f;sscanf(gtLine.c_str(), "%f,%f,%f,%f", &xmin, &ymin, &width, &height);if (gtFile.fail() || xmin < 0.f || ymin < 0.f || width < 0.f || height < 0.f){cout << "error: could not parse sequence gt file" << endl;return EXIT_FAILURE;}initBB = FloatRect(xmin*scaleW, ymin*scaleH, width*scaleW, height*scaleH);}Tracker tracker(conf);//使用conf类，初始化Tracker类if (!conf.quietMode)//quietMode模式下，不显示结果，只运算{namedWindow("result");}Mat result(conf.frameHeight, conf.frameWidth, CV_8UC3);bool paused = false;bool doInitialise = false;srand(conf.seed);for (int frameInd = startFrame; frameInd <= endFrame; ++frameInd){cout << "frame num is: " << frameInd << endl;//qyyMat frame;if (useCamera){Mat frameOrig;cap >> frameOrig;resize(frameOrig, frame, Size(conf.frameWidth, conf.frameHeight));//imshow("result",frame);//qyy//waitKey(0);//qyyflip(frame, frame, 1);//作者把视频左右对称翻转了，不知道为什么这么做？//imshow("result", frame);//qyy//waitKey(0);//qyyframe.copyTo(result);if (doInitialise){if (tracker.IsInitialised()){tracker.Reset();}else{tracker.Initialise(frame, initBB);}doInitialise = false;}else if (!tracker.IsInitialised()){rectangle(result, initBB, CV_RGB(255, 255, 255));//没有初始化，就在result上画白色框框}}else{char imgPath[256];sprintf(imgPath, imgFormat.c_str(), frameInd);Mat frameOrig = cv::imread(imgPath, 0);//第二个参数flag指定读取的颜色类型，=0表示读取为灰度图像cout << "frameOrig.channels: " << frameOrig.channels() << endl;//qyyif (frameOrig.empty()){cout << "error: could not read frame: " << imgPath << endl;return EXIT_FAILURE;}resize(frameOrig, frame, Size(conf.frameWidth, conf.frameHeight));cvtColor(frame, result, CV_GRAY2RGB);//作者读进来的时候是灰度图像，为了显示转换成3通道都是灰度图if (frameInd == startFrame)//如果是第一帧，初始化{tracker.Initialise(frame, initBB);}}if (tracker.IsInitialised())//如果初始化了，就开始跟踪{tracker.Track(frame);//跟踪程序，把tracker当做一个类来对待，很清晰明了啊，赞一个；算法都在这里面实现if (!conf.quietMode && conf.debugMode){tracker.Debug();//debug模式下，可以开启很多额外的窗口显示}rectangle(result, tracker.GetBB(), CV_RGB(0, 255, 0));//使用绿色框，画出跟踪的效果if (outFile)//这里是得到的矩形框，存储到txt文本中{const FloatRect& bb = tracker.GetBB();outFile << bb.XMin() / scaleW << "," << bb.YMin() / scaleH << "," << bb.Width() / scaleW << "," << bb.Height() / scaleH << flush << endl;cout << "cout to file: " << bb.XMin() / scaleW << "," << bb.YMin() / scaleH << "," << bb.Width() / scaleW << "," << bb.Height() / scaleH << endl;}}if (!conf.quietMode)//如果使用的是摄像头，作者提供了几个按键来选择是否初始化，我用的是OTB数据集，就不管这个了{imshow("result", result);int key = waitKey(paused ? 0 : 1);if (key != -1){if (key == 27 || key == 113) // esc q{break;}else if (key == 112) // p{paused = !paused;}else if (key == 105 && useCamera)//i{doInitialise = true;cout << "initialised !" << endl;//qyy}}if (conf.debugMode && frameInd == endFrame){cout << "\n\nend of sequence, press any key to exit" << endl;//waitKey();}}}if (outFile.is_open()){outFile.close();}return EXIT_SUCCESS;}

所以，后面我主要关注tracker这个类做了什么，我们看到在main.cpp中调用了tracker.Initialize Debug Track这几个成员函数，所以这几个函数是作者算法实现的关键。