libvips/libsrc/convolution/im_convf.c
2008-11-02 22:11:01 +00:00

353 lines
8.3 KiB
C

/* @(#) Convolve an image with a DOUBLEMASK. Image can have any number of bands,
* @(#) any non-complex type. Output is IM_BANDFMT_FLOAT for all non-complex inputs
* @(#) except IM_BANDFMT_DOUBLE, which gives IM_BANDFMT_DOUBLE.
* @(#)
* @(#) int
* @(#) im_convf( in, out, mask )
* @(#) IMAGE *in, *out;
* @(#) DOUBLEMASK *mask;
* @(#)
* @(#) Returns either 0 (success) or -1 (fail)
* @(#)
*
* Copyright: 1990, N. Dessipris.
*
* Author: Nicos Dessipris & Kirk Martinez
* Written on: 29/04/1991
* Modified on: 19/05/1991
* 8/7/93 JC
* - adapted for partial v2
* - memory leaks fixed
* - ANSIfied
* 12/7/93 JC
* - adapted im_convbi() to im_convbf()
* 7/10/94 JC
* - new IM_ARRAY() macro
* - evalend callbacks
* - more typedef
* 9/3/01 JC
* - redone from im_conv()
* 27/7/01 JC
* - rejects masks with scale == 0
* 7/4/04
* - now uses im_embed() with edge stretching on the input, not
* the output
* - sets Xoffset / Yoffset
* 11/11/05
* - simpler inner loop avoids gcc4 bug
*/
/*
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 <limits.h>
#include <assert.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Our parameters ... we take a copy of the mask argument, plus we make a
* smaller version with the zeros squeezed out.
*/
typedef struct {
IMAGE *in;
IMAGE *out;
DOUBLEMASK *mask; /* Copy of mask arg */
int nnz; /* Number of non-zero mask elements */
double *coeff; /* Array of non-zero mask coefficients */
} Conv;
static int
conv_close( Conv *conv )
{
if( conv->mask ) {
(void) im_free_dmask( conv->mask );
conv->mask = NULL;
}
return( 0 );
}
static Conv *
conv_new( IMAGE *in, IMAGE *out, DOUBLEMASK *mask )
{
Conv *conv = IM_NEW( out, Conv );
const int ne = mask->xsize * mask->ysize;
int i;
if( !conv )
return( NULL );
conv->in = in;
conv->out = out;
conv->mask = NULL;
conv->nnz = 0;
conv->coeff = NULL;
if( im_add_close_callback( out,
(im_callback_fn) conv_close, conv, NULL ) ||
!(conv->coeff = IM_ARRAY( out, ne, double )) ||
!(conv->mask = im_dup_dmask( mask, "conv_mask" )) )
return( NULL );
/* Find non-zero mask elements.
*/
for( i = 0; i < ne; i++ )
if( mask->coeff[i] )
conv->coeff[conv->nnz++] = mask->coeff[i];
return( conv );
}
/* Our sequence value.
*/
typedef struct {
Conv *conv;
REGION *ir; /* Input region */
int *offsets; /* Offsets for each non-zero matrix element */
PEL **pts; /* Per-non-zero mask element image pointers */
} ConvSequence;
/* Free a sequence value.
*/
static int
conv_stop( void *vseq, void *a, void *b )
{
ConvSequence *seq = (ConvSequence *) vseq;
IM_FREEF( im_region_free, seq->ir );
return( 0 );
}
/* Convolution start function.
*/
static void *
conv_start( IMAGE *out, void *a, void *b )
{
IMAGE *in = (IMAGE *) a;
Conv *conv = (Conv *) b;
ConvSequence *seq;
if( !(seq = IM_NEW( out, ConvSequence )) )
return( NULL );
/* Init!
*/
seq->conv = conv;
seq->ir = NULL;
seq->pts = NULL;
/* Attach region and arrays.
*/
seq->ir = im_region_create( in );
seq->offsets = IM_ARRAY( out, conv->nnz, int );
seq->pts = IM_ARRAY( out, conv->nnz, PEL * );
if( !seq->ir || !seq->offsets || !seq->pts ) {
conv_stop( seq, in, conv );
return( NULL );
}
return( (void *) seq );
}
#define INNER sum += *t++ * (*p++)[x]
#define CONV_FLOAT( ITYPE, OTYPE ) { \
OTYPE *q = (OTYPE *) IM_REGION_ADDR( or, le, y ); \
\
for( x = 0; x < sz; x++ ) { \
double sum = 0; \
double *t = conv->coeff; \
ITYPE **p = (ITYPE **) seq->pts; \
\
z = 0; \
IM_UNROLL( conv->nnz, INNER ); \
\
sum = (sum / mask->scale) + mask->offset; \
\
q[x] = sum; \
} \
}
/* Convolve!
*/
static int
conv_gen( REGION *or, void *vseq, void *a, void *b )
{
ConvSequence *seq = (ConvSequence *) vseq;
IMAGE *in = (IMAGE *) a;
Conv *conv = (Conv *) b;
REGION *ir = seq->ir;
DOUBLEMASK *mask = conv->mask;
Rect *r = &or->valid;
Rect s;
int le = r->left;
int to = r->top;
int bo = IM_RECT_BOTTOM(r);
int sz = IM_REGION_N_ELEMENTS( or );
int x, y, z, i;
/* Prepare the section of the input image we need. A little larger
* than the section of the output image we are producing.
*/
s = *r;
s.width += mask->xsize - 1;
s.height += mask->ysize - 1;
if( im_prepare( ir, &s ) )
return( -1 );
/* Fill offset array.
*/
z = 0;
for( i = 0, y = 0; y < mask->ysize; y++ )
for( x = 0; x < mask->xsize; x++, i++ )
if( mask->coeff[i] )
seq->offsets[z++] =
IM_REGION_ADDR( ir, x + le, y + to ) -
IM_REGION_ADDR( ir, le, to );
for( y = to; y < bo; y++ ) {
/* Init pts for this line of PELs.
*/
for( z = 0; z < conv->nnz; z++ )
seq->pts[z] = seq->offsets[z] +
(PEL *) IM_REGION_ADDR( ir, le, y );
switch( in->BandFmt ) {
case IM_BANDFMT_UCHAR:
CONV_FLOAT( unsigned char, float ); break;
case IM_BANDFMT_CHAR:
CONV_FLOAT( signed char, float ); break;
case IM_BANDFMT_USHORT:
CONV_FLOAT( unsigned short, float ); break;
case IM_BANDFMT_SHORT:
CONV_FLOAT( signed short, float ); break;
case IM_BANDFMT_UINT:
CONV_FLOAT( unsigned int, float ); break;
case IM_BANDFMT_INT:
CONV_FLOAT( signed int, float ); break;
case IM_BANDFMT_FLOAT:
CONV_FLOAT( float, float ); break;
case IM_BANDFMT_DOUBLE:
CONV_FLOAT( double, double ); break;
default:
assert( 0 );
}
}
return( 0 );
}
int
im_convf_raw( IMAGE *in, IMAGE *out, DOUBLEMASK *mask )
{
Conv *conv;
/* Check parameters.
*/
if( !in || in->Coding != IM_CODING_NONE || im_iscomplex( in ) ) {
im_error( "im_convf",
"%s", _( "non-complex uncoded only" ) );
return( -1 );
}
if( !mask || mask->xsize > 1000 || mask->ysize > 1000 ||
mask->xsize <= 0 || mask->ysize <= 0 || !mask->coeff ||
mask->scale == 0 ) {
im_error( "im_convf", "%s", _( "nonsense mask parameters" ) );
return( -1 );
}
if( im_piocheck( in, out ) )
return( -1 );
if( !(conv = conv_new( in, out, mask )) )
return( -1 );
/* Prepare output. Consider a 7x7 mask and a 7x7 image --- the output
* would be 1x1.
*/
if( im_cp_desc( out, in ) )
return( -1 );
if( im_isint( in ) ) {
out->Bbits = IM_BBITS_FLOAT;
out->BandFmt = IM_BANDFMT_FLOAT;
}
out->Xsize -= mask->xsize - 1;
out->Ysize -= mask->ysize - 1;
if( out->Xsize <= 0 || out->Ysize <= 0 ) {
im_error( "im_convf", "%s", _( "image too small for mask" ) );
return( -1 );
}
/* Set demand hints. FATSTRIP is good for us, as THINSTRIP will cause
* too many recalculations on overlaps.
*/
if( im_demand_hint( out, IM_FATSTRIP, in, NULL ) )
return( -1 );
if( im_generate( out, conv_start, conv_gen, conv_stop, in, conv ) )
return( -1 );
out->Xoffset = -mask->xsize / 2;
out->Yoffset = -mask->ysize / 2;
return( 0 );
}
/* The above, with a border to make out the same size as in.
*/
int
im_convf( IMAGE *in, IMAGE *out, DOUBLEMASK *mask )
{
IMAGE *t1 = im_open_local( out, "im_convf intermediate", "p" );
if( !t1 ||
im_embed( in, t1, 1, mask->xsize / 2, mask->ysize / 2,
in->Xsize + mask->xsize - 1,
in->Ysize + mask->ysize - 1 ) ||
im_convf_raw( t1, out, mask ) )
return( -1 );
out->Xoffset = 0;
out->Yoffset = 0;
return( 0 );
}