libvips/libvips/arithmetic/im_remainder.c

404 lines
9.9 KiB
C

/* im_remainder.c
*
* 2/8/99 JC
* - im_divide adapted to make im_remainder
* 8/5/02 JC
* - im_remainderconst added
* - im_remainderconst_vec added
* 27/9/04
* - updated for 1 band $op n band image -> n band image case
* 26/2/07
* - oop, broken for _vec case :-(
* 14/5/08
* - better /0 test
* 27/8/08
* - revise upcasting system
* - add gtkdoc comments
*/
/*
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 WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Integer remainder-after-division.
*/
#define ILOOP( IN, OUT ) { \
IN *p1 = (IN *) in[0]; \
IN *p2 = (IN *) in[1]; \
OUT *q = (OUT *) out; \
\
for( x = 0; x < sz; x++ ) \
if( p2[x] ) \
q[x] = (int) p1[x] % (int) p2[x]; \
else \
q[x] = -1; \
}
/* Float remainder-after-division.
*/
#define FLOOP( IN, OUT ) { \
IN *p1 = (IN *) in[0]; \
IN *p2 = (IN *) in[1]; \
OUT *q = (OUT *) out; \
\
for( x = 0; x < sz; x++ ) { \
double a = p1[x]; \
double b = p2[x]; \
\
if( b ) \
q[x] = a - b * floor (a / b); \
else \
q[x] = -1; \
} \
}
static void
remainder_buffer( PEL **in, PEL *out, int width, IMAGE *im )
{
int x;
int sz = width * im->Bands;
switch( im->BandFmt ) {
case IM_BANDFMT_CHAR: ILOOP( signed char, signed char ); break;
case IM_BANDFMT_UCHAR: ILOOP( unsigned char, unsigned char ); break;
case IM_BANDFMT_SHORT: ILOOP( signed short, signed short ); break;
case IM_BANDFMT_USHORT: ILOOP( unsigned short, unsigned short ); break;
case IM_BANDFMT_INT: ILOOP( signed int, signed int ); break;
case IM_BANDFMT_UINT: ILOOP( unsigned int, unsigned int ); break;
case IM_BANDFMT_FLOAT: FLOOP( float, float ); break;
case IM_BANDFMT_DOUBLE: FLOOP( double, double ); break;
default:
assert( 0 );
}
}
/* Save a bit of typing.
*/
#define UC IM_BANDFMT_UCHAR
#define C IM_BANDFMT_CHAR
#define US IM_BANDFMT_USHORT
#define S IM_BANDFMT_SHORT
#define UI IM_BANDFMT_UINT
#define I IM_BANDFMT_INT
#define F IM_BANDFMT_FLOAT
#define X IM_BANDFMT_COMPLEX
#define D IM_BANDFMT_DOUBLE
#define DX IM_BANDFMT_DPCOMPLEX
/* Type promotion for remainder. Same as input, except float/complex which are
* signed int. Keep in sync with remainder_buffer() above.
*/
static int bandfmt_remainder[10] = {
/* UC C US S UI I F X D DX */
UC, C, US, S, UI, I, F, X, D, DX
};
/**
* im_remainder:
* @in1: input #IMAGE 1
* @in2: input #IMAGE 2
* @out: output #IMAGE
*
* This operation calculates @in1 % @in2 (remainder after division) and writes
* the result to @out. The images must be the same size. They may have any
* non-complex format. For float types, im_remainder() calculates a - b *
* floor (a / b).
*
* If the number of bands differs, one of the images
* must have one band. In this case, an n-band image is formed from the
* one-band image by joining n copies of the one-band image together, and then
* the two n-band images are operated upon.
*
* The two input images are cast up to the smallest common type (see table
* Smallest common format in
* <link linkend="VIPS-arithmetic">arithmetic</link>), and that format is the
* result type.
*
* See also: im_remainderconst(), im_divide().
*
* Returns: 0 on success, -1 on error
*/
int
im_remainder( IMAGE *in1, IMAGE *in2, IMAGE *out )
{
return( im__arith_binary( "im_remainder",
in1, in2, out,
bandfmt_remainder,
(im_wrapmany_fn) remainder_buffer, NULL ) );
}
/* Cast a vector of double to a vector of TYPE.
*/
#define CAST( TYPE ) { \
TYPE *tq = (TYPE *) q; \
\
for( i = 0; i < n; i++ ) \
tq[i] = (TYPE) p[i]; \
}
/* Make a pixel of output type from a realvec.
*/
static PEL *
make_pixel( IMAGE *out, int n, double *p )
{
PEL *q;
int i;
g_assert( n == out->Bands );
if( !(q = IM_ARRAY( out, IM_IMAGE_SIZEOF_PEL( out ), PEL )) )
return( NULL );
switch( out->BandFmt ) {
case IM_BANDFMT_CHAR: CAST( signed char ); break;
case IM_BANDFMT_UCHAR: CAST( unsigned char ); break;
case IM_BANDFMT_SHORT: CAST( signed short ); break;
case IM_BANDFMT_USHORT: CAST( unsigned short ); break;
case IM_BANDFMT_INT: CAST( signed int ); break;
case IM_BANDFMT_UINT: CAST( unsigned int ); break;
default:
g_assert( 0 );
}
return( q );
}
int
im__arith_binary_const( const char *name,
IMAGE *in, IMAGE *out, int n, double *c,
int format_table[10],
im_wrapone_fn fn, void *a )
{
int i;
PEL *vector;
if( im_piocheck( in, out ) ||
im_check_vector( name, n, in ) ||
im_check_uncoded( name, in ) )
return( -1 );
if( im_cp_desc( out, in ) )
return( -1 );
out->BandFmt = format_table[in->BandFmt];
out->Bbits = im_bits_of_fmt( out->BandFmt );
/* Cast vector to output type.
*/
/*
need to handle case where vector == 1 but bands == (eg.) 3
*/
if( !(vector = make_pixel( out, n, c )) )
return( -1 );
if( im_wrapone( in, out, fn, a, vector ) )
return( -1 );
return( 0 );
}
/* Parameters saved here.
*/
typedef struct _Remainderconst {
IMAGE *in;
IMAGE *out;
int n;
int *c;
} Remainderconst;
/* Integer remainder-after-divide.
*/
#define ICONST1LOOP( TYPE ) { \
TYPE *p = (TYPE *) in; \
TYPE *q = (TYPE *) out; \
\
for( x = 0; x < sz; x++ ) \
q[x] = p[x] % c; \
}
static void
remainderconst1_buffer( PEL *in, PEL *out, int width, Remainderconst *rc )
{
IMAGE *im = rc->in;
int sz = width * im->Bands;
int c = rc->c[0];
int x;
switch( im->BandFmt ) {
case IM_BANDFMT_CHAR: ICONST1LOOP( signed char ); break;
case IM_BANDFMT_UCHAR: ICONST1LOOP( unsigned char ); break;
case IM_BANDFMT_SHORT: ICONST1LOOP( signed short ); break;
case IM_BANDFMT_USHORT: ICONST1LOOP( unsigned short ); break;
case IM_BANDFMT_INT: ICONST1LOOP( signed int ); break;
case IM_BANDFMT_UINT: ICONST1LOOP( unsigned int ); break;
default:
assert( 0 );
}
}
#define ICONSTLOOP( TYPE ) { \
TYPE *p = (TYPE *) in; \
TYPE *q = (TYPE *) out; \
\
for( i = 0, x = 0; x < width; x++ ) \
for( k = 0; k < b; k++, i++ ) \
q[i] = p[i] % c[k]; \
}
static void
remainderconst_buffer( PEL *in, PEL *out, int width, Remainderconst *rc )
{
IMAGE *im = rc->in;
int b = im->Bands;
int *c = rc->c;
int i, x, k;
switch( im->BandFmt ) {
case IM_BANDFMT_CHAR: ICONSTLOOP( signed char ); break;
case IM_BANDFMT_UCHAR: ICONSTLOOP( unsigned char ); break;
case IM_BANDFMT_SHORT: ICONSTLOOP( signed short ); break;
case IM_BANDFMT_USHORT: ICONSTLOOP( unsigned short ); break;
case IM_BANDFMT_INT: ICONSTLOOP( signed int ); break;
case IM_BANDFMT_UINT: ICONSTLOOP( unsigned int ); break;
default:
assert( 0 );
}
}
/**
* im_remainderconst_vec:
* @in: input #IMAGE
* @out: output #IMAGE
* @n: number of elements in array
* @c: array of constants
*
* This operation calculates @in % @c (remainder after division by constant)
* and writes the result to @out. The image must be one of the integer types.
*
* If the array of constants has one element, that constant is used for each
* image band. If the array has more than one element, it must have the same
* number of elements as there are bands in the image, and one array element
* is used for each band.
*
* See also: im_remainder(), im_divide().
*
* Returns: 0 on success, -1 on error
*/
int
im_remainderconst_vec( IMAGE *in, IMAGE *out, int n, double *c )
{
Remainderconst *rc;
int i;
/* Basic checks.
*/
if( im_piocheck( in, out ) ||
im_check_vector( "im_remainder", n, in ) ||
im_check_uncoded( "im_remainder", in ) ||
im_check_int( "im_remainder", in ) )
return( -1 );
if( im_cp_desc( out, in ) )
return( -1 );
/* Take a copy of the parameters.
*/
if( !(rc = IM_NEW( out, Remainderconst )) ||
!(rc->c = IM_ARRAY( out, n, int )) )
return( -1 );
rc->in = in;
rc->out = out;
rc->n = n;
for( i = 0; i < n; i++ ) {
/* Cast down to int ... we pass in double for consistency with
* the other _vec functions.
*/
if( c[i] != (int) c[i] )
im_warn( "im_remainderconst_vec",
_( "float constant %g truncated to integer" ),
c[i] );
rc->c[i] = c[i];
if( rc->c[i] == 0 ) {
im_error( "im_remainderconst_vec",
"%s", _( "division by zero" ) );
return( -1 );
}
}
if( n == 1 ) {
if( im_wrapone( in, out,
(im_wrapone_fn) remainderconst1_buffer, rc, NULL ) )
return( -1 );
}
else {
if( im_wrapone( in, out,
(im_wrapone_fn) remainderconst_buffer, rc, NULL ) )
return( -1 );
}
return( 0 );
}
/**
* im_remainderconst:
* @in: input #IMAGE
* @out: output #IMAGE
* @c: constant
*
* This operation calculates @in % @c (remainder after division by constant)
* and writes the result to @out. The image must be one of the integer types.
*
* See also: im_remainderconst_vec(), im_divide().
*
* Returns: 0 on success, -1 on error
*/
int
im_remainderconst( IMAGE *in, IMAGE *out, double c )
{
return( im_remainderconst_vec( in, out, 1, &c ) );
}