template <typename PointInT, typename PointOutT> void
pcl::SIFTKeypoint<PointInT, PointOutT>::detectKeypointsForOctave (
const PointCloudIn &input,
KdTree &tree,
float base_scale, int nr_scales_per_octave, PointCloudOut &output)
{
// Compute the difference of Gaussians (DoG) scale space
std::vector<float> scales (nr_scales_per_octave + 3);
for (int i_scale = 0; i_scale <= nr_scales_per_octave + 2; ++i_scale)
{
scales[i_scale] = base_scale * pow (2.0, (1.0 * i_scale - 1) / nr_scales_per_octave);
}
Eigen::MatrixXf diff_of_gauss;
computeScaleSpace (input, tree, scales, diff_of_gauss);
// Find extrema in the DoG scale space
std::vector<int> extrema_indices, extrema_scales;
findScaleSpaceExtrema (input, tree, diff_of_gauss, extrema_indices, extrema_scales);
// Add keypoints to output
for (size_t i_keypoint = 0; i_keypoint < extrema_indices.size (); ++i_keypoint)
{
PointOutT keypoint;
const int &keypoint_index = extrema_indices[i_keypoint];
keypoint.x = input.points[keypoint_index].x;
keypoint.y = input.points[keypoint_index].y;
keypoint.z = input.points[keypoint_index].z;
keypoint.scale = scales[extrema_scales[i_keypoint]];
output.points.push_back (keypoint);
}
}
template <typename PointInT, typename PointOutT> void
pcl::SIFTKeypoint<PointInT, PointOutT>::detectKeypointsForOctave (
const PointCloudIn &input, KdTree &tree, float base_scale, int nr_scales_per_octave,
PointCloudOut &output, pcl::PointIndices &indices)
{
// Compute the difference of Gaussians (DoG) scale space
std::vector<float> scales (nr_scales_per_octave + 3);
for (int i_scale = 0; i_scale <= nr_scales_per_octave + 2; ++i_scale)
{
scales[i_scale] = base_scale * powf (2.0f, (1.0f * static_cast<float> (i_scale) - 1.0f) / static_cast<float> (nr_scales_per_octave));
}
Eigen::MatrixXf diff_of_gauss;
computeScaleSpace (input, tree, scales, diff_of_gauss);
// Find extrema in the DoG scale space
std::vector<int> extrema_indices, extrema_scales;
findScaleSpaceExtrema (input, tree, diff_of_gauss, extrema_indices, extrema_scales);
output.points.reserve (output.points.size () + extrema_indices.size ());
indices.indices.reserve (indices.indices.size () + extrema_indices.size ());
// Save scale?
if (scale_idx_ != -1)
{
// Add keypoints to output
for (size_t i_keypoint = 0; i_keypoint < extrema_indices.size (); ++i_keypoint)
{
PointOutT keypoint;
const int &keypoint_index = extrema_indices[i_keypoint];
keypoint.x = input.points[keypoint_index].x;
keypoint.y = input.points[keypoint_index].y;
keypoint.z = input.points[keypoint_index].z;
memcpy (reinterpret_cast<char*> (&keypoint) + out_fields_[scale_idx_].offset,
&scales[extrema_scales[i_keypoint]], sizeof (float));
output.points.push_back (keypoint);
indices.indices.push_back (keypoint_index);
}
}
else
{
// Add keypoints to output
for (size_t i_keypoint = 0; i_keypoint < extrema_indices.size (); ++i_keypoint)
{
PointOutT keypoint;
const int &keypoint_index = extrema_indices[i_keypoint];
keypoint.x = input.points[keypoint_index].x;
keypoint.y = input.points[keypoint_index].y;
keypoint.z = input.points[keypoint_index].z;
output.points.push_back (keypoint);
indices.indices.push_back (keypoint_index);
}
}
}
