public void process(double c_x, double c_y, double scale, double orientation, SurfFeature desc) {
// determine where this feature lies inside the scale-space
int imageIndex = ss.scaleToImageIndex(scale);
double pixelScale = ss.imageIndexToPixelScale(imageIndex);
process(c_x, c_y, scale, orientation, imageIndex, pixelScale, desc);
}
/**
* Compute the descriptor with information on which level in the scale-space to use.
*
* @param c_x Location of feature in input image
* @param c_y Location of feature in input image
* @param scale Size of the feature in the input image
* @param orientation Orientation of the feature
* @param imageIndex Which octave contains the feature
* @param pixelScale The scale of a pixel in the octave
* @param desc (Output) storage for the descriptor
*/
public void process(
double c_x,
double c_y,
double scale,
double orientation,
int imageIndex,
double pixelScale,
SurfFeature desc) {
image = ss.getPyramidLayer(imageIndex);
derivX = ss.getDerivativeX(imageIndex);
derivY = ss.getDerivativeY(imageIndex);
for (int i = 0; i < desc.value.length; i++) desc.value[i] = 0;
for (int i = 0; i < histograms.length; i++)
for (int j = 0; j < histograms[i].length; j++) histograms[i][j] = 0;
// account for the scale of the image in each octave
constructHistograms(c_x / pixelScale, c_y / pixelScale, scale / pixelScale, orientation);
computeDescriptor(desc);
}
/**
* Processes the image and extracts SIFT features
*
* @param input input image
*/
public void process(ImageFloat32 input) {
features.reset();
featureScales.reset();
featureAngles.reset();
location.reset();
ss.constructPyramid(input);
ss.computeFeatureIntensity();
ss.computeDerivatives();
detector.process(ss);
orientation.setScaleSpace(ss);
describe.setScaleSpace(ss);
FastQueue<ScalePoint> found = detector.getFoundPoints();
for (int i = 0; i < found.size; i++) {
ScalePoint sp = found.data[i];
orientation.process(sp.x, sp.y, sp.scale);
GrowQueue_F64 angles = orientation.getOrientations();
int imageIndex = orientation.getImageIndex();
double pixelScale = orientation.getPixelScale();
for (int j = 0; j < angles.size; j++) {
SurfFeature desc = features.grow();
double yaw = angles.data[j];
describe.process(sp.x, sp.y, sp.scale, yaw, imageIndex, pixelScale, desc);
desc.laplacianPositive = sp.white;
featureScales.push(sp.scale);
featureAngles.push(yaw);
location.grow().set(sp.x, sp.y);
}
}
}
