Scilab Wavelet Toolbox Function
Last update : Feburary 2006

dwt2 - two dimensional fast discrete wavelet transform

Calling Sequence

[cA,cH,cV,cD]=dwt2(img,wavename,[extension_method])

Parameters

Description

This function performs two dimensional fast discrete wavelet transform and get four coefficients, approximation and details. Different signal extension methods affect the result except haar ('haar') or daubechies wavelet (db1). Detailed algorithm is fully described in userguide.

Examples


-->img=rand(64,64);
-->[cA,cH,cV,cD]=dwt2(img,'db2','zpd');

-->sig=rand(1,64);
-->[cA,cH,cV,cD]=dwt2(sig,'db2','zpd');
Please use dwt instead!

-->[cA,cH,cV,cD]=dwt2(3,'db2','symh');  
Please input image matrixes rather than vectors!

  

See Also

dwt ,   idwt ,   idwt2