108 lines
2.3 KiB
C
108 lines
2.3 KiB
C
|
/* @(#) Multiplies two DOUBLEMASKs. Result matrix is made and returned.
|
||
|
* @(#) Pass the filename to set for the output.
|
||
|
* @(#)
|
||
|
* @(#) DOUBLEMASK *
|
||
|
* @(#) im_matmul( in1, in2, name )
|
||
|
* @(#) DOUBLEMASK *in1, *in2;
|
||
|
* @(#) char *name;
|
||
|
* @(#)
|
||
|
* @(#) NULL for error.
|
||
|
*
|
||
|
* Copyright: 1990, K. Martinez and J. Cupitt
|
||
|
*
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
|
||
|
This file is part of VIPS.
|
||
|
|
||
|
VIPS is free software; you can redistribute it and/or modify
|
||
|
it under the terms of the GNU Lesser General Public License as published by
|
||
|
the Free Software Foundation; either version 2 of the License, or
|
||
|
(at your option) any later version.
|
||
|
|
||
|
This program is distributed in the hope that it will be useful,
|
||
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
GNU Lesser General Public License for more details.
|
||
|
|
||
|
You should have received a copy of the GNU Lesser General Public License
|
||
|
along with this program; if not, write to the Free Software
|
||
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||
|
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
|
||
|
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
|
||
|
|
||
|
*/
|
||
|
|
||
|
#ifdef HAVE_CONFIG_H
|
||
|
#include <config.h>
|
||
|
#endif /*HAVE_CONFIG_H*/
|
||
|
#include <vips/intl.h>
|
||
|
|
||
|
#include <stdio.h>
|
||
|
|
||
|
#include <vips/vips.h>
|
||
|
|
||
|
#ifdef WITH_DMALLOC
|
||
|
#include <dmalloc.h>
|
||
|
#endif /*WITH_DMALLOC*/
|
||
|
|
||
|
/* MATRIX MULTIPLY?
|
||
|
*/
|
||
|
DOUBLEMASK *
|
||
|
im_matmul( DOUBLEMASK *in1, DOUBLEMASK *in2, const char *name )
|
||
|
{
|
||
|
int xc, yc, col;
|
||
|
double sum;
|
||
|
DOUBLEMASK *mat;
|
||
|
double *out, *a, *b;
|
||
|
double *s1, *s2;
|
||
|
|
||
|
/* Check matrix sizes.
|
||
|
*/
|
||
|
if( in1->xsize != in2->ysize ) {
|
||
|
im_errormsg( "im_matmul: bad sizes" );
|
||
|
return( NULL );
|
||
|
}
|
||
|
|
||
|
/* Allocate output matrix.
|
||
|
*/
|
||
|
if( !(mat = im_create_dmask( name, in2->xsize, in1->ysize )) ) {
|
||
|
im_errormsg( "im_matmul: unable to allocate output mask" );
|
||
|
return( NULL );
|
||
|
}
|
||
|
|
||
|
/* Multiply.
|
||
|
*/
|
||
|
out = mat->coeff;
|
||
|
s1 = in1->coeff;
|
||
|
|
||
|
for( yc = 0; yc < in1->ysize; yc++ ) {
|
||
|
s2 = in2->coeff;
|
||
|
|
||
|
for( col = 0; col < in2->xsize; col++ ) {
|
||
|
/* Get ready to sweep a row.
|
||
|
*/
|
||
|
sum = 0.0;
|
||
|
a = s1;
|
||
|
b = s2;
|
||
|
|
||
|
for( sum = 0.0, xc = 0; xc < in1->xsize; xc++ ) {
|
||
|
sum += *a++ * *b;
|
||
|
b += in2->xsize;
|
||
|
}
|
||
|
|
||
|
*out++ = sum;
|
||
|
s2++;
|
||
|
}
|
||
|
|
||
|
s1 += in1->xsize;
|
||
|
}
|
||
|
|
||
|
return( mat );
|
||
|
}
|