Compute Dense SIFT features in OpenCV 3.0

edit

yes, the DenseFeatureDetector is gone in 3.0. but it's no biggie to create your own grid of KeyPoints:

int step = 10; // 10 pixels spacing between kp's

vector<KeyPoint> kps;
for (int i=step; i<img.rows-step; i+=step)
{
    for (int j=step; j<img.cols-step; j+=step)
    {
        // x,y,radius
        kps.push_back(KeyPoint(float(j), float(i), float(step)));
    }
}

Ptr<xfeatures2d::SIFT> sift = xfeatures2d::SIFT::create();
sift->compute(img,kps,features);