filt2ls

(To be removed) Transform quadruplet of filters to lifting scheme

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    filt2ls will be removed in a future release. Use liftingScheme instead. For more information, see Version History.

    Syntax

    LS = filt2ls(LoD,HiD,LoR,HiR)

    Description

    LS = filt2ls(LoD,HiD,LoR,HiR) returns the lifting scheme LS associated with the four input filters LoD, HiD, LoR, and HiR that verify the perfect reconstruction condition.

    example

    Examples

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    Open Live Script

    Obtain the filters associated with the db2 wavelet.

    [LoD,HiD,LoR,HiR] = wfilters('db2')
    LoD = 1×4

   -0.1294    0.2241    0.8365    0.4830


    HiD = 1×4

   -0.4830    0.8365   -0.2241   -0.1294


    LoR = 1×4

    0.4830    0.8365    0.2241   -0.1294


    HiR = 1×4

   -0.1294   -0.2241    0.8365   -0.4830

    Obtain the lifting scheme associated with the filters.

    LS = filt2ls(LoD,HiD,LoR,HiR);
disp(LS)
     	 Wavelet               : 'custom' 
	 LiftingSteps          : [3 × 1] liftingStep 
	 NormalizationFactors  : [0.29886 3.346] 
	 CustomLowpassFilter   : [  ] 


 Details of LiftingSteps :
            Type: 'predict'
    Coefficients: 0.5774
        MaxOrder: 0

            Type: 'update'
    Coefficients: [-0.4330 2.7990]
        MaxOrder: 0

            Type: 'predict'
    Coefficients: -0.3333
        MaxOrder: 1

    Input Arguments

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    Wavelet decomposition filters, specified as a pair of even-length real-valued vectors. LoD is the lowpass decomposition filter, and HiD is the highpass decomposition filter. The lengths of LoD and HiD must be equal. See wfilters for additional information.

    Data Types: double

    Wavelet reconstruction filters, specified as a pair of even-length real-valued vectors. LoD is the lowpass reconstruction filter, and HiD is the highpass reconstruction filter. The lengths of LoR and HiR must be equal. See wfilters for additional information.

    Data Types: double

    Output Arguments

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    Lifting scheme, returned as a liftingScheme object.

    Data Types: cell

    Version History

    Introduced before R2006a

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    See Also

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