libvips/libvips/arithmetic/im_lintra.c
2010-07-31 10:35:57 +00:00

360 lines
9.2 KiB
C

/* im_lintra.c -- linear transform
*
* Copyright: 1990, N. Dessipris, based on im_powtra()
* Author: Nicos Dessipris
* Written on: 02/05/1990
* Modified on:
* 23/4/93 JC
* - adapted to work with partial images
* 1/7/93 JC
* - adapted for partial v2
* 7/10/94 JC
* - new IM_NEW()
* - more typedefs
* 9/2/95 JC
* - adapted for im_wrap...
* - operations on complex images now just transform the real channel
* 29/9/95 JC
* - complex was broken
* 15/4/97 JC
* - return(0) missing from generate, arrgh!
* 1/7/98 JC
* - im_lintra_vec added
* 3/8/02 JC
* - fall back to im_copy() for a == 1, b == 0
* 10/10/02 JC
* - auug, failing to multiply imag for complex! (thanks matt)
* 10/12/02 JC
* - removed im_copy() fallback ... meant that output format could change
* with value :-( very confusing
* 30/6/04
* - added 1 band image * n band vector case
* 8/12/06
* - add liboil support
* 9/9/09
* - gtkdoc comment, minor reformat
* 31/7/10
* - remove liboil
*/
/*
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 <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#include <vips/internal.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Struct we need for im_generate().
*/
typedef struct {
int n; /* Number of bands of constants */
double *a, *b;
} LintraInfo;
/* Define what we do for each band element type. Non-complex input, any
* output.
*/
#define LOOP( IN, OUT ) { \
IN *p = (IN *) in; \
OUT *q = (OUT *) out; \
\
for( x = 0; x < sz; x++ ) \
q[x] = a * (OUT) p[x] + b; \
}
/* Complex input, complex output.
*/
#define LOOPCMPLX( IN, OUT ) { \
IN *p = (IN *) in; \
OUT *q = (OUT *) out; \
\
for( x = 0; x < sz; x++ ) { \
q[0] = a * p[0] + b; \
q[1] = a * p[1]; \
q += 2; \
p += 2; \
} \
}
/* Lintra a buffer, 1 set of scale/offset.
*/
static int
lintra1_gen( PEL *in, PEL *out, int width, IMAGE *im, LintraInfo *inf )
{
double a = inf->a[0];
double b = inf->b[0];
int sz = width * im->Bands;
int x;
/* Lintra all input types.
*/
switch( im->BandFmt ) {
case IM_BANDFMT_UCHAR: LOOP( unsigned char, float ); break;
case IM_BANDFMT_CHAR: LOOP( signed char, float ); break;
case IM_BANDFMT_USHORT: LOOP( unsigned short, float ); break;
case IM_BANDFMT_SHORT: LOOP( signed short, float ); break;
case IM_BANDFMT_UINT: LOOP( unsigned int, float ); break;
case IM_BANDFMT_INT: LOOP( signed int, float ); break;
case IM_BANDFMT_FLOAT: LOOP( float, float ); break;
case IM_BANDFMT_DOUBLE: LOOP( double, double ); break;
case IM_BANDFMT_COMPLEX: LOOPCMPLX( float, float ); break;
case IM_BANDFMT_DPCOMPLEX: LOOPCMPLX( double, double ); break;
default:
g_assert( 0 );
}
return( 0 );
}
/* Define what we do for each band element type. Non-complex input, any
* output.
*/
#define LOOPN( IN, OUT ) { \
IN *p = (IN *) in; \
OUT *q = (OUT *) out; \
\
for( i = 0, x = 0; x < width; x++ ) \
for( k = 0; k < nb; k++, i++ ) \
q[i] = a[k] * (OUT) p[i] + b[k]; \
}
/* Complex input, complex output.
*/
#define LOOPCMPLXN( IN, OUT ) { \
IN *p = (IN *) in; \
OUT *q = (OUT *) out; \
\
for( x = 0; x < width; x++ ) \
for( k = 0; k < nb; k++ ) { \
q[0] = a[k] * p[0] + b[k]; \
q[1] = a[k] * p[1]; \
q += 2; \
p += 2; \
} \
}
/* Lintra a buffer, n set of scale/offset.
*/
static int
lintran_gen( PEL *in, PEL *out, int width, IMAGE *im, LintraInfo *inf )
{
double *a = inf->a;
double *b = inf->b;
int nb = im->Bands;
int i, x, k;
/* Lintra all input types.
*/
switch( im->BandFmt ) {
case IM_BANDFMT_UCHAR: LOOPN( unsigned char, float ); break;
case IM_BANDFMT_CHAR: LOOPN( signed char, float ); break;
case IM_BANDFMT_USHORT: LOOPN( unsigned short, float ); break;
case IM_BANDFMT_SHORT: LOOPN( signed short, float ); break;
case IM_BANDFMT_UINT: LOOPN( unsigned int, float ); break;
case IM_BANDFMT_INT: LOOPN( signed int, float ); break;
case IM_BANDFMT_FLOAT: LOOPN( float, float ); break;
case IM_BANDFMT_DOUBLE: LOOPN( double, double ); break;
case IM_BANDFMT_COMPLEX: LOOPCMPLXN( float, float ); break;
case IM_BANDFMT_DPCOMPLEX: LOOPCMPLXN( double, double ); break;
default:
g_assert( 0 );
}
return( 0 );
}
/* 1 band image, n band vector.
*/
#define LOOPNV( IN, OUT ) { \
IN *p = (IN *) in; \
OUT *q = (OUT *) out; \
\
for( i = 0, x = 0; x < width; x++ ) { \
OUT v = p[x]; \
\
for( k = 0; k < nb; k++, i++ ) \
q[i] = a[k] * v + b[k]; \
} \
}
#define LOOPCMPLXNV( IN, OUT ) { \
IN *p = (IN *) in; \
OUT *q = (OUT *) out; \
\
for( x = 0; x < width; x++ ) { \
OUT p0 = p[0]; \
OUT p1 = p[1]; \
\
for( k = 0; k < nb; k++ ) { \
q[0] = a[k] * p0 + b[k]; \
q[1] = a[k] * p1; \
q += 2; \
} \
\
p += 2; \
} \
}
static int
lintranv_gen( PEL *in, PEL *out, int width, IMAGE *im, LintraInfo *inf )
{
double *a = inf->a;
double *b = inf->b;
int nb = inf->n;
int i, x, k;
/* Lintra all input types.
*/
switch( im->BandFmt ) {
case IM_BANDFMT_UCHAR: LOOPNV( unsigned char, float ); break;
case IM_BANDFMT_CHAR: LOOPNV( signed char, float ); break;
case IM_BANDFMT_USHORT: LOOPNV( unsigned short, float ); break;
case IM_BANDFMT_SHORT: LOOPNV( signed short, float ); break;
case IM_BANDFMT_UINT: LOOPNV( unsigned int, float ); break;
case IM_BANDFMT_INT: LOOPNV( signed int, float ); break;
case IM_BANDFMT_FLOAT: LOOPNV( float, float ); break;
case IM_BANDFMT_DOUBLE: LOOPNV( double, double ); break;
case IM_BANDFMT_COMPLEX: LOOPCMPLXNV( float, float ); break;
case IM_BANDFMT_DPCOMPLEX: LOOPCMPLXNV( double, double ); break;
default:
g_assert( 0 );
}
return( 0 );
}
/**
* im_lintra_vec:
* @n: array size
* @a: array of constants for multiplication
* @in: image to transform
* @b: array of constants for addition
* @out: output image
*
* Pass an image through a linear transform - ie. @out = @in * @a + @b. Output
* is always float for integer input, double for double input, complex for
* complex input and double complex for double complex input.
*
* If the arrays of constants have just one element, that constant are used for
* all image bands. If the arrays have more than one element and they have
* the same number of elements as there are bands in the image, then
* one array element is used for each band. If the arrays have more than one
* element and the image only has a single band, the result is a many-band
* image where each band corresponds to one array element.
*
* See also: im_add(), im_lintra().
*
* Returns: 0 on success, -1 on error
*/
int
im_lintra_vec( int n, double *a, IMAGE *in, double *b, IMAGE *out )
{
LintraInfo *inf;
int i;
if( im_piocheck( in, out ) ||
im_check_vector( "im_lintra_vec", n, in ) ||
im_check_uncoded( "lintra_vec", in ) )
return( -1 );
/* Prepare output header.
*/
if( im_cp_desc( out, in ) )
return( -1 );
if( vips_bandfmt_isint( in->BandFmt ) )
out->BandFmt = IM_BANDFMT_FLOAT;
if( in->Bands == 1 )
out->Bands = n;
/* Make space for a little buffer.
*/
if( !(inf = IM_NEW( out, LintraInfo )) ||
!(inf->a = IM_ARRAY( out, n, double )) ||
!(inf->b = IM_ARRAY( out, n, double )) )
return( -1 );
inf->n = n;
for( i = 0; i < n; i++ ) {
inf->a[i] = a[i];
inf->b[i] = b[i];
}
/* Generate!
*/
if( n == 1 ) {
if( im_wrapone( in, out,
(im_wrapone_fn) lintra1_gen, in, inf ) )
return( -1 );
}
else if( in->Bands == 1 ) {
if( im_wrapone( in, out,
(im_wrapone_fn) lintranv_gen, in, inf ) )
return( -1 );
}
else {
if( im_wrapone( in, out,
(im_wrapone_fn) lintran_gen, in, inf ) )
return( -1 );
}
return( 0 );
}
/**
* im_lintra:
* @a: constant for multiplication
* @in: image to transform
* @b: constant for addition
* @out: output image
*
* Pass an image through a linear transform - ie. @out = @in * @a + @b. Output
* is always float for integer input, double for double input, complex for
* complex input and double complex for double complex input.
*
* See also: im_add(), im_lintra_vec().
*
* Returns: 0 on success, -1 on error
*/
int
im_lintra( double a, IMAGE *in, double b, IMAGE *out )
{
return( im_lintra_vec( 1, &a, in, &b, out ) );
}