Abstract: A system and method for improving the detail of an input digital signal, such as a signal comprising a two dimensional image, can be implemented by computing first and second order gradients of the input signal. These gradients can be represented as quaternions. The logarithm of the quaternions can be used to determine the magnitude and orientation of gradient vectors in the input signal. This gradient magnitude and gradient orientation information can be used to construct an output digital signal that has greater detail than the input digital signal.

Abstract: A system and method for improving the detail of an input digital signal, such as a signal comprising a two dimensional image, can be implemented by computing first and second order gradients of the input signal. These gradients can be represented as quaternions. The logarithm of the quaternions can be used to determine the magnitude and orientation of gradient vectors in the input signal. This gradient magnitude and gradient orientation information can be used to construct an output digital signal that has greater detail than the input digital signal.