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<p>kim's algorithm supposedly has a cache layer, i did not dig deep enough into opencv implementation to know how to have a workable version that works with exposure problem. </p> <h3>notes</h3> <ul> <li>opencv book(which i havent read) should have the info you need if it's there at all</li> <li>this is only 1 channel and not in yuv although it can be extended</li> <li>needs more work on speed/testing (you can of course turn on optimization in compiler)</li> <li>background subtraction is a buzzy word. try "change detection"</li> </ul> <p>bgfg_cb.h</p> <pre><code>#ifndef __bgfg_cb_h__ #define __bgfg_cb_h__ //http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.148.9778&rep=rep1&type=pdf #include "opencv2/core/core.hpp" #include "opencv2/imgproc/imgproc.hpp" #include "opencv2/highgui/highgui.hpp" #include <iostream> #include <time.h> using namespace cv; using namespace std; struct codeword { float min; float max; float f; float l; int first; int last; bool isStale; }; extern int alpha ; extern float beta ; extern int Tdel ,Tadd , Th; void initializeCodebook(int w,int h); void update_cb(Mat& frame); void fg_cb(Mat& frame,Mat& fg); #endif </code></pre> <p>bgfg_cb.cpp</p> <pre><code>#include "opencv2/core/core.hpp" #include "opencv2/imgproc/imgproc.hpp" #include "opencv2/highgui/highgui.hpp" #include <iostream> #include <time.h> #include "bgfg_cb.h" using namespace cv; using namespace std; vector<codeword> **cbMain; vector<codeword> **cbCache; int t=0; int alpha = 10;//knob float beta =1; int Tdel = 200,Tadd = 150, Th= 200;//knobs void initializeCodebook(int w,int h) { cbMain = new vector<codeword>*[w]; for(int i = 0; i < w; ++i) cbMain[i] = new vector<codeword>[h]; cbCache = new vector<codeword>*[w]; for(int i = 0; i < w; ++i) cbCache[i] = new vector<codeword>[h]; } void update_cb(Mat& frame) { if(t>10) return; for(int i=0;i<frame.rows;i++) { for(int j=0;j<frame.cols;j++) { int pix = frame.at<uchar>(i,j); vector<codeword>& cm =cbMain[i][j]; bool found = false; for(int k=0;k<cm.size();k++) { if(cm[k].min<=pix && pix<=cm[k].max && !found) { found=true; cm[k].min = ((pix-alpha)+(cm[k].f*cm[k].min))/(cm[k].f+1); cm[k].max = ((pix+alpha)+(cm[k].f*cm[k].max))/(cm[k].f+1); cm[k].l=0; cm[k].last=t; cm[k].f++; }else { cm[k].l++; } } if(!found) { codeword n={}; n.min=max(0,pix-alpha); n.max=min(255,pix+alpha); n.f=1; n.l=0; n.first=t; n.last=t; cm.push_back(n); } } } t++; } void fg_cb(Mat& frame,Mat& fg) { fg=Mat::zeros(frame.size(),CV_8UC1); if(cbMain==0) initializeCodebook(frame.rows,frame.cols); if(t<10) { update_cb(frame); return; } for(int i=0;i<frame.rows;i++) { for(int j=0;j<frame.cols;j++) { int pix = frame.at<uchar>(i,j); vector<codeword>& cm = cbMain[i][j]; bool found = false; for(int k=0;k<cm.size();k++) { if(cm[k].min<=pix && pix<=cm[k].max && !found) { cm[k].min = ((1-beta)*(pix-alpha)) + (beta*cm[k].min); cm[k].max = ((1-beta)*(pix+alpha)) + (beta*cm[k].max); cm[k].l=0; cm[k].first=t; cm[k].f++; found=true; }else { cm[k].l++; } } cm.erase( remove_if(cm.begin(), cm.end(), [](codeword& c) { return c.l>=Tdel;} ), cm.end() ); fg.at<uchar>(i,j) = found?0:255; if(found) continue; found = false; vector<codeword>& cc = cbCache[i][j]; for(int k=0;k<cc.size();k++) { if(cc[k].min<=pix && pix<=cc[k].max && !found) { cc[k].min = ((1-beta)*(pix-alpha)) + (beta*cc[k].min); cc[k].max = ((1-beta)*(pix+alpha)) + (beta*cc[k].max); cc[k].l=0; cc[k].first=t; cc[k].f++; found=true; }else { cc[k].l++; } } if(!found) { codeword n={}; n.min=max(0,pix-alpha); n.max=min(255,pix+alpha); n.f=1; n.l=0; n.first=t; n.last=t; cc.push_back(n); } cc.erase( remove_if(cc.begin(), cc.end(), [](codeword& c) { return c.l>=Th;} ), cc.end() ); for(vector<codeword>::iterator it=cc.begin();it!=cc.end();it++) { if(it->f>Tadd) { cm.push_back(*it); } } cc.erase( remove_if(cc.begin(), cc.end(), [](codeword& c) { return c.f>Tadd;} ), cc.end() ); } } } </code></pre> <p>main.cpp</p> <pre><code>#include "opencv2/core/core.hpp" #include "opencv2/imgproc/imgproc.hpp" #include "opencv2/highgui/highgui.hpp" #include "bgfg_cb.h" #include <iostream> using namespace cv; using namespace std; void proc() { Mat frame,fg,gray; VideoCapture cap("C:/Downloads/S2_L1.tar/S2_L1/Crowd_PETS09/S2/L1/Time_12-34/View_001/frame_%04d.jpg"); cap >> frame; initializeCodebook(frame.rows,frame.cols); for(;;) { cap>>frame; cvtColor(frame,gray,CV_BGR2GRAY); fg_cb(gray,fg); Mat cc; imshow("fg",fg); waitKey(1); } } int main(int argc, char ** argv) { proc(); cin.ignore(1); return 0; } </code></pre>
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1. POCodeBook background subtraction with moving objects
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1. USZaw Lin
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1. COhmmm, thanks i will give it a try, thanks
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2. COif ur fine with a patented algo, then maybe try this as well http://stackoverflow.com/questions/13818574/is-it-possible-to-use-vibe-algorithm-implemented-in-opencv-for-systema-without/15049240
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3. COI will check that one too
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