VectorCode

Cython code for filtering vector fields.

alignment(vectors, selem_index, selem_vector, selem_offset, sink, parameter)

Compute alignment of central vector with neighboring vectors.

Algorithm

For each central voxel

1. compute a set of weights to neighboring vectors via the scalar product of the central vector with the structural element vectors

2. compute the scalar product of the central vector with the neighbouring vectors

3. from the weighed sum

alignment_weighted(vectors, weights, selem_index, selem_vector, selem_offset, sink, parameter)

Compute alignment of central vector with neighboring vectors.

Algorithm

For each central voxel

1. compute a set of weights to neighboring vectors via the scalar product of the central vector with the structural element vectors weighted by the weights

2. compute the scalar product of the central vector with the neighbouring vectors

3. from the weighed sum

orientation(vectors, selem_index, selem_vector, selem_offset, sink, parameter)

Compute orientation alignment of central vector with neighboring vectors.

Algorithm

For each central voxel

1. compute a set of matched orientation weights to neighboring vectors via the absolute value scalar product of the central vector with the structural element vectors (e.g. direction vectors from center)

2. compute the absolute value of the scalar product of the central vector with the neighbouring vectors

3. from the weighed sum

orientation_ellipsoid(vectors, selem_index, selem_vector, selem_offset, sink, parameter)

Compute similarity of central vector with neighbors weighted by a central vector aligned ellipsoidal form.

Algorithm

For each central voxel

1. compute weights to neighboring vectors from a quadratic from with mayor axis aligned with the central vector

2. compute the absolute value of the scalar product of the central vector with the neighbouring vectors

3. from the weighed sum

orientation_ellipsoid_weighted(vectors, weights, selem_index, selem_vector, selem_offset, sink, parameter)

Compute similarity of central vector with neighbors weighted by a central vector aligned ellipsoidal form.

Algorithm

For each central voxel

1. compute weights to neighboring vectors from a quadratic from with mayor axis aligned with the central vector

2. compute the absolute value of the scalar product of the central vector with the neighbouring vectors

3. from the weighed sum

orientation_weighted(vectors, weights, selem_index, selem_vector, selem_offset, sink, parameter)

Compute orientation alignment of central vector with neighboring vectors.

Algorithm

For each central voxel

1. compute as set of weights to neighboring vectors via the absolute value scalar product of the central vector with the structural element vectors (e.g. direction vectors from center), and further multiply by the input weights for the vectors.

2. compute the absolute value of the scalar product of the central vector with the neighbouring vectors

3. from the weighed sum

similarity(vectors, selem_index, selem_vector, selem_offset, sink, parameter)

Compute sum of scalar products of the center vector with neighbouring vectors defined by the structural element.

Algorithm

For each center voxel compute the scalar products of the center vector with the neighbouring vectors defined by the structural element and sum them up.

similarity_weighted(vectors, weights, selem_index, selem_vector, selem_offset, sink, parameter)

Compute weighted sum of scalar products of the center vector with neighboring vectors.

Algorithm

For each center voxel compute the scalar products of the center vector with the neighbouring vectors defined by the structural element, and compute the weighted average using the weights for each vector.