goodFeaturesToTrack OpenCV 2.4 Extremely Slow compared to Opencv1 - c++

Question

I have this really strange issue and I think I might be doing something wrong, but I have an opencv1 implementation for Pyramidal Lucas Kanade and an opencv2 implementation. The difference is that the opencv2 takes MUCH longer to run (in particular the goodFeaturesToTrack function) vs. the opencv1. In addition, including the opencv2 libs and headers in the opencv1 implmentation results in that one becoming extremely slow as well (we're talking about 0.002 s per two images vs. 1 second per two images). Am I doing something wrong?
Windows 7, 64 bit. Here is the opencv2 code that runs really slow, at about 1 frame per second. As I said, taking the opencv1 implementation and switching library version causes the same slow down by a factor of 10 or more. I think this is very weird and google came up with no information! THANKS!!!
#include <opencv2/opencv.hpp>
#include <iostream>
#include <vector>
#include <cmath>
using namespace cv;
using namespace std;
int64 now, then;
double elapsed_seconds, tickspersecond=cvGetTickFrequency() * 1.0e6;
int main(int argc, char** argv)
{
// Load two images and allocate other structures
Mat imgA = imread("0000.png", CV_LOAD_IMAGE_GRAYSCALE);
Mat imgB = imread("0001.png", CV_LOAD_IMAGE_GRAYSCALE);
Size img_sz = imgA.size();
Mat imgC(img_sz,1);
int win_size = 15;
int maxCorners = 100;
double qualityLevel = 0.05;
double minDistance = 2.0;
int blockSize = 3;
double k = 0.04;
std::vector<cv::Point2f> cornersA;
cornersA.reserve(maxCorners);
std::vector<cv::Point2f> cornersB;
cornersB.reserve(maxCorners);
then = cvGetTickCount();
goodFeaturesToTrack( imgA,cornersA,maxCorners,qualityLevel,minDistance,cv::Mat(),blockSize,true);
goodFeaturesToTrack( imgB,cornersB,maxCorners,qualityLevel,minDistance,cv::Mat(),blockSize,true);
now = cvGetTickCount();
cout << (double)(now - then) / tickspersecond;
cornerSubPix( imgA, cornersA, Size( win_size, win_size ), Size( -1, -1 ),
TermCriteria( CV_TERMCRIT_ITER | CV_TERMCRIT_EPS, 20, 0.03 ) );
cornerSubPix( imgB, cornersB, Size( win_size, win_size ), Size( -1, -1 ),
TermCriteria( CV_TERMCRIT_ITER | CV_TERMCRIT_EPS, 20, 0.03 ) );
// Call Lucas Kanade algorithm
CvSize pyr_sz = Size( img_sz.width+8, img_sz.height/3 );
std::vector<uchar> features_found;
features_found.reserve(maxCorners);
std::vector<float> feature_errors;
feature_errors.reserve(maxCorners);
calcOpticalFlowPyrLK( imgA, imgB, cornersA, cornersB, features_found, feature_errors ,
Size( win_size, win_size ), 5,
cvTermCriteria( CV_TERMCRIT_ITER | CV_TERMCRIT_EPS, 20, 0.3 ), 0 );
// Make an image of the results
for( int i=0; i < features_found.size(); i++ ){
// cout<<"Error is "<<feature_errors[i]<<endl;
//continue;
//cout<<"Got it"<<endl;
Point p0( ceil( cornersA[i].x ), ceil( cornersA[i].y ) );
Point p1( ceil( cornersB[i].x ), ceil( cornersB[i].y ) );
line( imgC, p0, p1, CV_RGB(255,255,255), 2 );
}
namedWindow( "ImageA", 0 );
namedWindow( "ImageB", 0 );
namedWindow( "LKpyr_OpticalFlow", 0 );
imshow( "ImageA", imgA );
imshow( "ImageB", imgB );
imshow( "LKpyr_OpticalFlow", imgC );
cvWaitKey(0);
return 0;
}

Answer 1

You're probably using the debug libraries (*d.lib) instead of the release ones. I had this same problem with ~1-2s per call for goodFeaturesToTrack() and switching to release solved it.

Answer 2

Why are you calling goodFeaturesToTrack twice ?
Call it once to get cornersA and then use LK to identify the same corners / features in imgB.