ivan@78: /*
ivan@78: File Name: MIDWT.c
ivan@78: Last Modification Date:	06/14/95	13:01:15
ivan@78: Current Version: MIDWT.c	2.4
ivan@78: File Creation Date: Wed Oct 12 08:44:43 1994
ivan@78: Author: Markus Lang  <lang@jazz.rice.edu>
ivan@78: 
ivan@78: Copyright (c) 2000 RICE UNIVERSITY. All rights reserved.
ivan@78: Created by Markus Lang, Department of ECE, Rice University. 
ivan@78: 
ivan@78: This software is distributed and licensed to you on a non-exclusive 
ivan@78: basis, free-of-charge. Redistribution and use in source and binary forms, 
ivan@78: with or without modification, are permitted provided that the following 
ivan@78: conditions are met:
ivan@78: 
ivan@78: 1. Redistribution of source code must retain the above copyright notice, 
ivan@78:    this list of conditions and the following disclaimer.
ivan@78: 2. Redistribution in binary form must reproduce the above copyright notice, 
ivan@78:    this list of conditions and the following disclaimer in the 
ivan@78:    documentation and/or other materials provided with the distribution.
ivan@78: 3. All advertising materials mentioning features or use of this software 
ivan@78:    must display the following acknowledgment: This product includes 
ivan@78:    software developed by Rice University, Houston, Texas and its contributors.
ivan@78: 4. Neither the name of the University nor the names of its contributors 
ivan@78:    may be used to endorse or promote products derived from this software 
ivan@78:    without specific prior written permission.
ivan@78: 
ivan@78: THIS SOFTWARE IS PROVIDED BY WILLIAM MARSH RICE UNIVERSITY, HOUSTON, TEXAS, 
ivan@78: AND CONTRIBUTORS AS IS AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, 
ivan@78: BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
ivan@78: FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RICE UNIVERSITY 
ivan@78: OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
ivan@78: EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
ivan@78: PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 
ivan@78: OR BUSINESS INTERRUPTIONS) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
ivan@78: WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 
ivan@78: OTHERWISE), PRODUCT LIABILITY, OR OTHERWISE ARISING IN ANY WAY OUT OF THE 
ivan@78: USE OF THIS SOFTWARE,  EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
ivan@78: 
ivan@78: For information on commercial licenses, contact Rice University's Office of 
ivan@78: Technology Transfer at techtran@rice.edu or (713) 348-6173
ivan@78: 
ivan@78: Change History: Fixed the code such that 1D vectors passed to it can be in
ivan@78:                 either passed as a row or column vector. Also took care of 
ivan@78: 		the code such that it will compile with both under standard
ivan@78: 		C compilers as well as for ANSI C compilers
ivan@78: 		Jan Erik Odegard <odegard@ece.rice.edu> Wed Jun 14 1995
ivan@78: 
ivan@78: 		Fix minor bug to allow maximum number of levels
ivan@78: 
ivan@78: decription of the matlab call:
ivan@78: %y = midwt(x,h,L);
ivan@78: % 
ivan@78: % function computes the inverse discrete wavelet transform y for a 1D or 2D
ivan@78: % input signal x.
ivan@78: %
ivan@78: %    Input:
ivan@78: %	x    : finite length 1D or 2D input signal (implicitely periodized)
ivan@78: %       h    : scaling filter
ivan@78: %       L    : number of levels. in case of a 1D signal length(x) must be
ivan@78: %              divisible by 2^L; in case of a 2D signal the row and the
ivan@78: %              column dimension must be divisible by 2^L.
ivan@78: %
ivan@78: % see also: mdwt, mrdwt, mirdwt
ivan@78: 
ivan@78: */
ivan@78: 
ivan@78: #include <math.h>
ivan@78: #include <stdio.h>
ivan@78: #include <inttypes.h>
ivan@78: 
ivan@78: #define max(A,B) (A > B ? A : B)
ivan@78: #define mat(a, i, j) (*(a + (m*(j)+i)))  /* macro for matrix indices */
ivan@78: 
ivan@78: 
ivan@78: #ifdef __STDC__
ivan@78: MIDWT(double *x, uintptr_t m, uintptr_t n, double *h, uintptr_t lh, uintptr_t L, double *y)
ivan@78: #else
ivan@78: MIDWT(x, m, n, h, lh, L, y)
ivan@78: double *x, *h, *y;
ivan@78: uintptr_t m, n, lh, L;
ivan@78: #endif
ivan@78: {
ivan@78:   double  *g0, *g1, *ydummyl, *ydummyh, *xdummy;
ivan@78:   uintptr_t i, j;
ivan@78:   uintptr_t actual_L, actual_m, actual_n, r_o_a, c_o_a, ir, ic, lhm1, lhhm1, sample_f;
ivan@78:   xdummy = (double *)(uintptr_t)mxCalloc(max(m,n),sizeof(double));
ivan@78:   ydummyl = (double *)(uintptr_t)mxCalloc(max(m,n)+lh/2-1,sizeof(double));
ivan@78:   ydummyh = (double *)(uintptr_t)mxCalloc(max(m,n)+lh/2-1,sizeof(double));
ivan@78:   g0 = (double *)(uintptr_t)mxCalloc(lh,sizeof(double));
ivan@78:   g1 = (double *)(uintptr_t)mxCalloc(lh,sizeof(double));
ivan@78: 
ivan@78:   if (n==1){
ivan@78:     n = m;
ivan@78:     m = 1;
ivan@78:   }
ivan@78:   /* synthesis lowpass and highpass */
ivan@78:   for (i=0; i<lh; i++){
ivan@78:     g0[i] = h[i];
ivan@78:     g1[i] = h[lh-i-1];
ivan@78:   }
ivan@78:   for (i=1; i<=lh; i+=2)
ivan@78:     g1[i] = -g1[i];
ivan@78:   
ivan@78:   lhm1 = lh - 1;
ivan@78:   lhhm1 = lh/2 - 1;
ivan@78:   /* 2^L */
ivan@78:   sample_f = 1;
ivan@78:   for (i=1; i<L; i++)
ivan@78:     sample_f = sample_f*2;
ivan@78:   
ivan@78:   if (m>1)
ivan@78:     actual_m = m/sample_f;
ivan@78:   else 
ivan@78:     actual_m = 1;
ivan@78:   actual_n = n/sample_f;
ivan@78: 
ivan@78:   for (i=0; i<(m*n); i++)
ivan@78:     x[i] = y[i];
ivan@78:   
ivan@78:   /* main loop */
ivan@78:   for (actual_L=L; actual_L >= 1; actual_L--){
ivan@78:     r_o_a = actual_m/2;
ivan@78:     c_o_a = actual_n/2;
ivan@78:     
ivan@78:     /* go by columns in case of a 2D signal*/
ivan@78:     if (m>1){
ivan@78:       for (ic=0; ic<actual_n; ic++){            /* loop over column */
ivan@78: 	/* store in dummy variables */
ivan@78: 	ir = r_o_a;
ivan@78: 	for (i=0; i<r_o_a; i++){    
ivan@78: 	  ydummyl[i+lhhm1] = mat(x, i, ic);  
ivan@78: 	  ydummyh[i+lhhm1] = mat(x, ir++, ic);  
ivan@78: 	}
ivan@78: 	/* perform filtering lowpass and highpass*/
ivan@78: 	bpsconv(xdummy, r_o_a, g0, g1, lhm1, lhhm1, ydummyl, ydummyh); 
ivan@78: 	/* restore dummy variables in matrix */
ivan@78: 	for (i=0; i<actual_m; i++)
ivan@78: 	  mat(x, i, ic) = xdummy[i];  
ivan@78:       }
ivan@78:     }
ivan@78:     /* go by rows */
ivan@78:     for (ir=0; ir<actual_m; ir++){            /* loop over rows */
ivan@78:       /* store in dummy variable */
ivan@78:       ic = c_o_a;
ivan@78:       for  (i=0; i<c_o_a; i++){    
ivan@78: 	ydummyl[i+lhhm1] = mat(x, ir, i);  
ivan@78: 	ydummyh[i+lhhm1] = mat(x, ir, ic++);  
ivan@78:       } 
ivan@78:       /* perform filtering lowpass and highpass*/
ivan@78:       bpsconv(xdummy, c_o_a, g0, g1, lhm1, lhhm1, ydummyl, ydummyh); 
ivan@78:       /* restore dummy variables in matrices */
ivan@78:       for (i=0; i<actual_n; i++)
ivan@78:         mat(x, ir, i) = xdummy[i];  
ivan@78:     }  
ivan@78:     if (m==1)
ivan@78:       actual_m = 1;
ivan@78:     else
ivan@78:       actual_m = actual_m*2;
ivan@78:     actual_n = actual_n*2;
ivan@78:   }
ivan@78: }
ivan@78: 
ivan@78: #ifdef __STDC__
ivan@78: bpsconv(double *x_out, uintptr_t lx, double *g0, double *g1, uintptr_t lhm1, 
ivan@78: 	uintptr_t lhhm1, double *x_inl, double *x_inh)
ivan@78: #else
ivan@78: bpsconv(x_out, lx, g0, g1, lhm1, lhhm1, x_inl, x_inh)
ivan@78: double *x_inl, *x_inh, *g0, *g1, *x_out;
ivan@78: uintptr_t lx, lhm1, lhhm1;
ivan@78: #endif
ivan@78: {
ivan@78:   uintptr_t i, j, ind, tj;
ivan@78:   double x0, x1;
ivan@78: 
ivan@78:   for (i=lhhm1-1; i > -1; i--){
ivan@78:     x_inl[i] = x_inl[lx+i];
ivan@78:     x_inh[i] = x_inh[lx+i];
ivan@78:   }
ivan@78:   ind = 0;
ivan@78:   for (i=0; i<(lx); i++){
ivan@78:     x0 = 0;
ivan@78:     x1 = 0;
ivan@78:     tj = -2;
ivan@78:     for (j=0; j<=lhhm1; j++){
ivan@78:       tj+=2;
ivan@78:       x0 = x0 + x_inl[i+j]*g0[lhm1-1-tj] + x_inh[i+j]*g1[lhm1-1-tj] ;
ivan@78:       x1 = x1 + x_inl[i+j]*g0[lhm1-tj] + x_inh[i+j]*g1[lhm1-tj] ;
ivan@78:     }
ivan@78:     x_out[ind++] = x0;
ivan@78:     x_out[ind++] = x1;
ivan@78:   }
ivan@78: }