void AffineAdaptedFeature2D::operator()(InputArray _image, InputArray _mask,
vector<KeyPoint>& _keypoints,
OutputArray _descriptors,
bool useProvidedKeypoints) const
{
Mat image = _image.getMat();
Mat mask = _mask.getMat();
CV_Assert(useProvidedKeypoints == false);
CV_Assert(!affineTransformParams.empty());
vector<vector<KeyPoint> > keypoints(affineTransformParams.size());
vector<Mat> descriptors(affineTransformParams.size());
#pragma omp parallel for
for(size_t paramsIndex = 0; paramsIndex < affineTransformParams.size(); paramsIndex++)
{
const Vec2f& params = affineTransformParams[paramsIndex];
const float tilt = params[0];
const float phi = params[1];
if(tilt == 1.f) // tilt
{
detectAndComputeImpl(image, mask, keypoints[paramsIndex], descriptors[paramsIndex]);
}
else
{
Mat transformedImage, transformedMask;
Mat Ainv = affineSkew(image, mask, tilt, phi, transformedImage, transformedMask);
detectAndComputeImpl(transformedImage, transformedMask, keypoints[paramsIndex], descriptors[paramsIndex]);
// correct keypoints coordinates
CV_Assert(Ainv.type() == CV_32FC1);
const float* Ainv_ptr = Ainv.ptr<const float>();
for(size_t kpIndex = 0; kpIndex < keypoints[paramsIndex].size(); kpIndex++)
{
KeyPoint& kp = keypoints[paramsIndex][kpIndex];
float tx = Ainv_ptr[0] * kp.pt.x + Ainv_ptr[1] * kp.pt.y + Ainv_ptr[2];
float ty = Ainv_ptr[3] * kp.pt.x + Ainv_ptr[4] * kp.pt.y + Ainv_ptr[5];
kp.pt.x = tx;
kp.pt.y = ty;
}
}
}
// copy keypoints and descriptors to the output
_keypoints.clear();
Mat allDescriptors;
for(size_t paramsIndex = 0; paramsIndex < affineTransformParams.size(); paramsIndex++)
{
_keypoints.insert(_keypoints.end(), keypoints[paramsIndex].begin(), keypoints[paramsIndex].end());
allDescriptors.push_back(descriptors[paramsIndex]);
}
_descriptors.create(allDescriptors.size(), allDescriptors.type());
Mat _descriptorsMat = _descriptors.getMat();
allDescriptors.copyTo(_descriptorsMat);
}
void ASiftDetector::detectAndCompute(const Mat& img, std::vector< KeyPoint >& keypoints, Mat& descriptors)
{
keypoints.clear();
descriptors = Mat(0, 128, CV_32F);
for(int tl = 1; tl < 6; tl++)
{
double t = pow(2, 0.5*tl);
for(int phi = 0; phi < 180; phi += 72.0/t)
{
std::vector<KeyPoint> kps;
Mat desc;
Mat timg, mask, Ai;
img.copyTo(timg);
affineSkew(t, phi, timg, mask, Ai);
#if 0
Mat img_disp;
bitwise_and(mask, timg, img_disp);
namedWindow( "Skew", WINDOW_AUTOSIZE );// Create a window for display.
imshow( "Skew", img_disp );
waitKey(0);
#endif
SiftFeatureDetector detector;
detector.detect(timg, kps, mask);
SiftDescriptorExtractor extractor;
extractor.compute(timg, kps, desc);
for(unsigned int i = 0; i < kps.size(); i++)
{
Point3f kpt(kps[i].pt.x, kps[i].pt.y, 1);
Mat kpt_t = Ai*Mat(kpt);
kps[i].pt.x = kpt_t.at<float>(0,0);
kps[i].pt.y = kpt_t.at<float>(1,0);
}
keypoints.insert(keypoints.end(), kps.begin(), kps.end());
descriptors.push_back(desc);
}
}
}