On the level lines and geometry of vector-valued images

In this letter, we extend the concept of level lines of scalar images to ve ctor-valued data. Consistent with the scalar case, we define the level-line s of vector-valued images as the integral curves of the directions of minim al vectorial change, This direction, and the magnitude of the change, are c omputed using classical Riemannian geometry. As an example of the use of th is new concept, we show how to visualize the basic geometry of vector-value d images with a scalar image.