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iowave2

$ \bigcirc$Name


iowave2 Reconstructs an image from an orthogonal wavelet transform




$ \bigcirc$Command Synopsis


iowave2 [-r NLevel] [-h HaarNLevel] [-e EdgeMode] [-p PrecondMode] [-i] [-n FilterNorm] WavTrans RecompImage ImpulseResponse [EdgeIR ]



-r NLevel : Start reconstruction from level NLevel (default 0)

-h HaarNLevel : Start reconstruction with Haar filter from level HaarNLevel down to level NLevel + 1

-e EdgeMode : Edge processing mode (0/1/2/3, default 3)

-p PrecondMode : Edge preconditionning mode (0/1/2, default 0)

-i : Invertible transform

-n FilterNorm : Filter taps normalization (0/1/2, default 2)

WavTrans : Input wavelet transform (wtrans2d)

RecompImage : Output reconstructed image (fimage)

ImpulseResponse : Impulse response of inner filters (fsignal)

EdgeIR : Impulse reponses of edge and preconditionning filters (fimage)




$ \bigcirc$Function Summary


void iowave2 (NumRec , Haar , Edge , Precond , Inverse , FilterNorm , Wtrans , Output , Ri , Edge_Ri )

int *NumRec ;

int *Haar ;

int *Edge ;

int *Precond ;

int *Inverse ;

int *FilterNorm ;

Wtrans2d Wtrans ;

Fimage Output ;

Fsignal Ri ;

Fimage Edge_Ri ;




$ \bigcirc$Description


iowave2 reconstructs an image from a sequence of sub-images forming a wavelet decomposition, according to the pyramidal algorithm of S. Mallat [Mal89]. The notations that are used here have been already defined in owave1 and owave2 modules' documentation, so the reader is refered there to see their signification.

WavTrans is the prefix name of a sequence of files containing the coefficients of a wavelet decomposition D11, D12,..., D1J, D21,...D2J, D31,..., D3J, AJ. iowave2 computes A0, i.e. the inverse wavelet transform of WavTrans.

As for owave2 this is a semi-separable and recursive transformation : Aj-1 is computed from Aj D1j, D2j, and D3j. One applies the one-dimensional inverse wavelet transform to each pair of corresponding lines in Aj and D1j and in D2j, and D3j. Then one applies the one-dimensional inverse wavelet transform to each pair of corresponding columns in the two resulting sub-images.

The edge processing methods are corresponding to those described for iowave1.

The complexity of the algorithm is roughly the same as for owave2.

The name of the files containing the sub-signals D11, D12,..., D1J, D21,...D2J, D31,..., D3J, AJ must have the same prefix WavTrans, and their syntax obeys the rules described in owave2. The sample values of the reconstructed signal are stored in the file RecompImage.

The coefficients hk of the filter's impulse response are read in the file ImpulseResponse. The coefficients of the filter's impulse response for computing the edge coefficients are read in the file EdgeIR.

These options should be tuned in the same way as they were for the decomposition (with the owave2 module).




$ \bigcirc$See Also


precond2d, sconvolve.

fezw, fiezw, fwivq, fwvq.


$ \bigcirc$Version 1.3


Last Modification date : Thu Jan 31 15:11:14 2002


$ \bigcirc$Author


Jean-Pierre D'Ales






next up previous contents index
Next: owave1 Up: Reference Previous: iowave1   Contents   Index
mw 2004-05-05