[ZZ] Matlab wavelet transform function dwt2 and wavedec2 coefficients extraction function Appcoef2 and Detcoef2

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DWT2 is a two-dimensional single-scale wavelet transform, which can decompose two-dimensional single-scale wavelet by specifying wavelet or decomposition filter.

And WAVEDEC2 is two scale wavelet decomposition.

A syntax format for DWT2 is [Ca,ch,cv,cd]=dwt2 (X, ' wname ');

The corresponding WAVEDEC2 syntax format is [C,S]=WAVEDEC2 (X,n, ' wname '), where N is a positive integer greater than 1.

That is, DWT2 can only do one decomposition of an input matrix x, and WAVEDEC2 may decompose the input matrix x n times.

http://blog.csdn.net/zhuyonghao123/article/details/7996013

WAVEDEC2: Multi-Layer Two-dimensional discrete wavelet transform function

[C,s] = WAVEDEC2 (x,n, ' wname ')

[C,s] = WAVEDEC2 (x,n,lo_d,hi_d)

APPCOEF2: Low frequency partial coefficients extraction of two-dimensional discrete wavelet transform

A = Appcoef2 (c,s, ' wname ', N)

A = Appcoef2 (c,s, ' wname ')

A = Appcoef2 (c,s,lo_r,hi_r)

A = Appcoef2 (c,s,lo_r,hi_r,n)

Detcoef2: Extraction of high frequency partial coefficients of two-dimensional discrete wavelet transform

D = Detcoef2 (o,c,s,n)

[ZZ] Matlab wavelet transform function dwt2 and wavedec2 coefficients extraction function Appcoef2 and Detcoef2