如何在MoG2中禁用陰影檢測

Question

我使用C++和Opencv 2.3.1進行背景扣除。我曾多次嘗試更改Mog2的參數以禁用影子檢測功能，我也嘗試了其他人在互聯網上提出的建議。但是，陰影檢測仍然啓用。

你能告訴我如何禁用它嗎？ 查看示例代碼和生成的掩碼。

//opencv 
#include < opencv2/opencv.hpp> 
#include < opencv2/core/core.hpp> 
#include < opencv2/highgui/highgui.hpp> 
#include < opencv2/video/background_segm.hpp> 
#include < opencv2/imgproc/imgproc.hpp> 
#include < opencv2/video/video.hpp> 

//C 
#include <stdio.h> 
//C++ 
#include <iostream> 
#include <sstream> 

using namespace cv; 
using namespace std; 

// Global variables 
Mat frame; //current frame 
Mat fgMaskMOG2; //fg mask fg mask generated by MOG method 
Ptr<BackgroundSubtractor> pMOG2; //MOG Background subtractor 
int keyboard; //input from keyboard 

//new variables 
int history = 1250; 
float varThreshold = 16; 
bool bShadowDetection = true; 

/* 
//added to remove the shadow 
unsigned char nShadowDetection = 0; 
float fTau = 0.5; 
//static const unsigned char nShadowDetection =(unsigned char)0; 
*/ 
    // Function Headers 
    void help(); 
    void processImages(char* firstFrameFilename); 

void help() 
{ 
cout 
    << "This program shows how to use background subtraction methods provided by " << endl 
    << " OpenCV. You can process images (-img)."          << endl                  
    << "Usage:"                  << endl 
    << "./bs -img <image filename>}"            << endl 
    << "for example: ./bs -img /data/images/1.png"         << endl 
    << endl; 
    } 

// morphological operation 

void morphOps(Mat &thresh){ 

    //create structuring element that will be used to "dilate" and "erode" image. 
    //the element chosen here is a 3px by 3px rectangle 

    Mat erodeElement = getStructuringElement(MORPH_RECT,Size(2,2)); //3x3 
    //dilate with larger element so make sure object is nicely visible 
    Mat dilateElement = getStructuringElement(MORPH_RECT,Size(1,1)); //8x8 

    erode(thresh,thresh,erodeElement); 
    erode(thresh,thresh,erodeElement); 


    dilate(thresh,thresh,dilateElement); 
    dilate(thresh,thresh,dilateElement); 

} 


// main function 

int main(int argc, char* argv[]) 
{ 

//print help information 
help(); 

//check for the input parameter correctness 
if(argc != 3) { 
    cerr <<"Incorret input list" << endl; 
    cerr <<"exiting..." << endl; 
    return EXIT_FAILURE; 
} 

    //create GUI windows 
    namedWindow("Frame"); 
    namedWindow("FG Mask MOG2 "); 

//create Background Subtractor objects 
//pMOG2 = new BackgroundSubtractorMOG2(); 
    pMOG2 = new BackgroundSubtractorMOG2(history, varThreshold,  bShadowDetection); 
//BackgroundSubtractorMOG2(int history, float varThreshold, bool bShadowDetection=1); 
    if(strcmp(argv[1], "-img") == 0) { 
    //input data coming from a sequence of images 
    processImages(argv[2]); 
} 
else { 
    //error in reading input parameters 
    cerr <<"Please, check the input parameters." << endl; 
    cerr <<"Exiting..." << endl; 
    return EXIT_FAILURE; 
} 
//destroy GUI windows 
destroyAllWindows(); 
return EXIT_SUCCESS; 
} 

//function processImages 

void processImages(char* fistFrameFilename) { 
    //read the first file of the sequence 
    frame = imread(fistFrameFilename); 
    if(frame.empty()){ 
    //error in opening the first image 
    cerr << "Unable to open first image frame: " << fistFrameFilename << endl; 
    exit(EXIT_FAILURE); 

//current image filename 
string fn(fistFrameFilename); 
//read input data. ESC or 'q' for quitting 
    while((char)keyboard != 'q' && (char)keyboard != 27){ 
    //update the background model 
    pMOG2->operator()(frame, fgMaskMOG2,-1); 
    //get the frame number and write it on the current frame 
    size_t index = fn.find_last_of("/"); 
    if(index == string::npos) { 
     index = fn.find_last_of("\\"); 
    } 
    size_t index2 = fn.find_last_of("."); 
    string prefix = fn.substr(0,index+1); 
    string suffix = fn.substr(index2); 
    string frameNumberString = fn.substr(index+1, index2-index-1); 
    istringstream iss(frameNumberString); 
    int frameNumber = 0; 
    iss >> frameNumber; 
    rectangle(frame, cv::Point(10, 2), cv::Point(100,20), 
       cv::Scalar(255,255,255), -1); 
    putText(frame, frameNumberString.c_str(), cv::Point(15, 15), 
      FONT_HERSHEY_SIMPLEX, 0.5 , cv::Scalar(0,0,0)); 
    //show the current frame and the fg masks 
    imshow("Frame", frame); 
    morphOps(fgMaskMOG2); 
    imshow("FG Mask MOG2 ", fgMaskMOG2); 
    //get the input from the keyboard 
    keyboard = waitKey(1); 
    //search for the next image in the sequence 
    ostringstream oss; 
    oss << (frameNumber + 1); 
    string nextFrameNumberString = oss.str(); 
    string nextFrameFilename = prefix + nextFrameNumberString + suffix; 
    //read the next frame 
    frame = imread(nextFrameFilename); 
    if(frame.empty()){ 
     //error in opening the next image in the sequence 
     cerr << "Unable to open image frame: " << nextFrameFilename << endl; 
     exit(EXIT_FAILURE); 
    } 
    //update the path of the current frame 
    fn.assign(nextFrameFilename); 

    // save subtracted images 
    string imageToSave =("output_MOG_" + frameNumberString + ".png"); 
    bool saved = imwrite( "D:\\SO\\temp\\" +imageToSave,fgMaskMOG2); 
    if(!saved) { 
    cerr << "Unable to save " << imageToSave << endl; 
     } 
} 
} 

}

Answer 1

承擔你的代碼看看the documentation

你有

bool bShadowDetection = true; 

改變它

bool bShadowDetection = false; 

編輯： OpenCV 3的BackgroundSubtractorMOG2類具有setShadowValue (int value)函數來設置陰影的灰度值。 設置灰度值爲零將消除陰影。

Answer 2

這取決於你真正想看到 - 如果你想陰影從分割分開：

bool bShadowDetection = true; 和使用 cv::threshold(Mask,Mask,254,255,cv::THRESH_BINARY); 後MOG2->apply()

你會得到完全一部分至極是在你的形象

和SRY的爽口這個{255} ...