libvips/libsrc/arithmetic/im_abs.c
2009-06-17 08:18:46 +00:00

268 lines
6.6 KiB
C

/** Find the absolute value of an image.
* Acts as a copy for UNSIGNED types, negate
* for int types, fabs() for float types, and calculate modulus for
* complex types.
*\file im_abs.c
*
* Copyright: 1990, N. Dessipris, based on im_powtra()
* Author: Nicos Dessipris
* Written on: 02/05/1990
* Modified on:
* 5/5/93 J.Cupitt
* - adapted from im_lintra to work with partial images
* - complex and signed support added
* 30/6/93 JC
* - adapted for partial v2
* - ANSI conversion
* - spe29873r6k3h()**!@lling errors removed
* 9/2/95 JC
* - adapted for im_wrap...
* 20/6/02 JC
* - tiny speed up
* 8/12/06
* - add liboil support
*/
/*
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 <assert.h>
#include <vips/vips.h>
#include <vips/internal.h>
#ifdef HAVE_LIBOIL
#include <liboil/liboil.h>
#endif /*HAVE_LIBOIL*/
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Integer abs operation: just test and negate.
*/
#define intabs(TYPE) \
{ \
TYPE *p = (TYPE *) in; \
TYPE *q = (TYPE *) out; \
int x; \
\
for( x = 0; x < sz; x++ ) { \
TYPE v = p[x]; \
\
if( v < 0 ) \
q[x] = 0 - v; \
else \
q[x] = v; \
} \
}
/* Float abs operation: call fabs().
*/
#define floatabs(TYPE)\
{\
TYPE *p = (TYPE *) in;\
TYPE *q = (TYPE *) out;\
int x; \
\
for( x = 0; x < sz; x++ )\
q[x] = fabs( p[x] );\
}
/* Complex abs operation: calculate modulus.
*/
#ifdef HAVE_HYPOT
#define complexabs(TYPE) { \
TYPE *p = (TYPE *) in; \
TYPE *q = (TYPE *) out; \
int i; \
\
for( i = 0; i < sz; i++ ) { \
q[i] = hypot( p[0], p[1] ); \
p += 2; \
} \
}
#else /*HAVE_HYPOT*/
#define complexabs(TYPE) { \
TYPE *p = (TYPE *) in; \
TYPE *q = (TYPE *) out; \
TYPE *q_stop = q + sz; \
\
while( q < q_stop ){ \
double rp = *p++; \
double ip = *p++; \
double abs_rp= fabs( rp ); \
double abs_ip= fabs( ip ); \
\
if( abs_rp > abs_ip ){ \
double temp= ip / rp; \
*q++= abs_rp * sqrt( 1.0 + temp * temp ); \
} \
else { \
double temp= rp / ip; \
*q++= abs_ip * sqrt( 1.0 + temp * temp ); \
} \
} \
}
#endif /*HAVE_HYPOT*/
/* Abs a buffer of PELs.
*/
static void
abs_gen( PEL *in, PEL *out, int width, IMAGE *im )
{
int sz = width * im->Bands;
/* Abs all input types.
*/
switch( im->BandFmt ) {
case IM_BANDFMT_CHAR:
#ifdef HAVE_LIBOIL
oil_abs_u8_s8( (uint8_t *) out, sizeof( uint8_t ),
(int8_t *) in, sizeof( int8_t ), sz );
#else /*!HAVE_LIBOIL*/
intabs( signed char );
#endif /*HAVE_LIBOIL*/
break;
case IM_BANDFMT_SHORT:
#ifdef HAVE_LIBOIL
oil_abs_u16_s16( (uint16_t *) out, sizeof( uint16_t ),
(int16_t *) in, sizeof( int16_t ), sz );
#else /*!HAVE_LIBOIL*/
intabs( signed short );
#endif /*HAVE_LIBOIL*/
break;
case IM_BANDFMT_INT:
#ifdef HAVE_LIBOIL
oil_abs_u32_s32( (uint32_t *) out, sizeof( uint32_t ),
(int32_t *) in, sizeof( int32_t ), sz );
#else /*!HAVE_LIBOIL*/
intabs( signed int );
#endif /*HAVE_LIBOIL*/
break;
case IM_BANDFMT_FLOAT:
#ifdef HAVE_LIBOIL
oil_abs_f32_f32( (float *) out, sizeof( float ),
(float *) in, sizeof( float ), sz );
#else /*!HAVE_LIBOIL*/
floatabs( float );
#endif /*HAVE_LIBOIL*/
break;
case IM_BANDFMT_DOUBLE:
#ifdef HAVE_LIBOIL
oil_abs_f64_f64( (double *) out, sizeof( double ),
(double *) in, sizeof( double ), sz );
#else /*!HAVE_LIBOIL*/
floatabs( float );
#endif /*HAVE_LIBOIL*/
break;
case IM_BANDFMT_COMPLEX: complexabs( float ); break;
case IM_BANDFMT_DPCOMPLEX: complexabs( double ); break;
default:
assert( 0 );
}
}
/** Abs of image.
*@param in is input IMAGE
*@param out is output IMAGE
*@return 0 on success, -1 on failure
*@see IMAGE
*/
int
im_abs( IMAGE *in, IMAGE *out )
{
/* Check args.
*/
if( in->Coding != IM_CODING_NONE ) {
im_error( "im_abs", "%s", _( "not uncoded" ) );
return( -1 );
}
/* Is this one of the unsigned types? Degenerate to im_copy() if it
* is.
*/
if( im_isuint( in ) )
return( im_copy( in, out ) );
/* Prepare output header. Output type == input type, except for
* complex.
*/
if( im_cp_desc( out, in ) )
return( -1 );
switch( in->BandFmt ) {
case IM_BANDFMT_CHAR:
case IM_BANDFMT_SHORT:
case IM_BANDFMT_INT:
case IM_BANDFMT_FLOAT:
case IM_BANDFMT_DOUBLE:
/* No action.
*/
break;
case IM_BANDFMT_COMPLEX:
out->Bbits = IM_BBITS_FLOAT;
out->BandFmt = IM_BANDFMT_FLOAT;
break;
case IM_BANDFMT_DPCOMPLEX:
out->Bbits = IM_BBITS_DOUBLE;
out->BandFmt = IM_BANDFMT_DOUBLE;
break;
default:
im_error( "im_abs", "%s", _( "unknown input type" ) );
return( -1 );
}
/* Generate!
*/
if( im_wrapone( in, out,
(im_wrapone_fn) abs_gen, in, NULL ) )
return( -1 );
return( 0 );
}