Orientation (computer Vision) - Relation To Gradients

Relation To Gradients

In image processing, the computation of the local image gradient is a common operation, e.g., for edge detection. If above is an edge, then its gradient is parallel to . As is already discussed above the gradient is not a unique representation of orientation. Also, in the case of a local region which is centered on a line, the image gradient is approximately zero. However, in this case the vector is still well-defined except for its sign. Therefore, is a more appropriate starting point for defining local orientation than the image gradient.