If there exist an E- pseudo scaling function φ and a " generalized " E-filter H ∈ Fφ such thatfor some unimodular, 2π - Z2 periodic function p0, where, then ψ is called an MRA E-tight frame wavelet.

This article summarizes the spatial domain,frequency domain and mixed edge detection methods in two-dimensional images,focuses on the super-wavelet edge detection method and its advantages,and then summarizes and compares them with the current edge detection methods in three-dimensional images and gives the direction of development.

Optical orthogonal code based on discrete hyper-wavelet transform;