Method and apparatus for processing or compressing n-dimensional signals by foveal filtering along trajectories

US6836569B2 · kind B2 · utility

Inventors

• Erwan Le Pennec · Paris, FR
• Stephane Mallat · Paris, FR

Key dates

• Filing date: Apr 13, 2001
• Grant date: Dec 28, 2004
• Expiry date: May 3, 2023

Classification

• Technology area (CPC G): Physics
• CPC primary: G06T9/007
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

Methods and apparatus for processing n-dimensional digitized signals with a foveal processing which constructs a sparse representation by taking advantage of the geometrical regularity of the signal structures. This invention can compress, restore, match and classify signals. Foveal coefficients are computed with one-dimensional inner products along trajectories of an n-directional trajectory list. The invention includes a trajectory finder which computes an n-directional trajectory list from the input n-dimensional signal, in order to choose optimal locations to compute the foveal coefficients. From foveal coefficients, a foveal reconstruction processor recovers a signal approximation which has the same geometrical structures as the input signal along the trajectories and which is regular away from these trajectories. A foveal residue can be calculated as a difference with the input signal. A bandelet processor decorrelates the foveal coefficients by applying invertible linear operators along each trajectory. Bandelet coefficients are inner products between the signal and n-dimensional bandelet vectors elongated along the trajectories. A geometric processor computes geometric coef…