libvips/libsrc/convolution/im_conv.c
John Cupitt 2219ad0703 stuff
2009-04-06 11:14:23 +00:00

588 lines
14 KiB
C

/* @(#) Convolve an image with an INTMASK. Image can have any number of bands,
* @(#) any non-complex type. Size and type of output image matches type of
* @(#) input image.
* @(#)
* @(#) int
* @(#) im_conv( in, out, mask )
* @(#) IMAGE *in, *out;
* @(#) INTMASK *mask;
* @(#)
* @(#) Also: im_conv_raw(). As above, but does not add a black border.
* @(#)
* @(#) Returns either 0 (success) or -1 (fail)
* @(#)
* @(#) Old code, kept for use of other old code in this package:
* @(#)
* @(#) Creates int luts for all non zero elm of the original mask;
* @(#) which is kept in buffer of length buffersize
* @(#) cnt is needed for freeing luts. Called by the above.
* @(#)
* @(#) int im__create_int_luts( buffer, buffersize, orig_luts, luts, cnt )
* @(#) int *buffer, buffersize;
* @(#) int **orig_luts, **luts, *cnt;
* @(#)
* @(#) Returns either 0 (sucess) 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
* 23/7/93 JC
* - inner loop unrolled with a switch - 25% speed-up!
* 13/12/93 JC
* - tiny rounding error removed
* 7/10/94 JC
* - new IM_ARRAY() macro
* - various simplifications
* - evalend callback added
* 1/2/95 JC
* - use of IM_REGION_ADDR() updated
* - output size was incorrect! see comment below
* - bug with large non-square matricies fixed too
* - uses new im_embed() function
* 13/7/98 JC
* - wierd bug ... im_free_imask is no longer directly called for close
* callback, caused SIGKILL on solaris 2.6 ... linker bug?
* 9/3/01 JC
* - reworked and simplified, about 10% faster
* - slightly better range clipping
* 27/7/01 JC
* - rejects masks with scale == 0
* 7/4/04
* - im_conv() 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
* 7/11/07
* - new evalstart/end callbacks
* 12/5/08
* - int rounding was +1 too much, argh
* - only rebuild the buffer offsets if bpl changes
* 5/4/09
* - tiny speedups and cleanups
* - add restrict, though it doesn't seem to help gcc
*/
/*
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;
INTMASK *mask; /* Copy of mask arg */
int nnz; /* Number of non-zero mask elements */
int *coeff; /* Array of non-zero mask coefficients */
int underflow; /* Global underflow/overflow counts */
int overflow;
} Conv;
static int
conv_close( Conv *conv )
{
IM_FREEF( im_free_imask, conv->mask );
return( 0 );
}
static int
conv_evalstart( Conv *conv )
{
/* Reset underflow/overflow count.
*/
conv->overflow = 0;
conv->underflow = 0;
return( 0 );
}
static int
conv_evalend( Conv *conv )
{
/* Print underflow/overflow count.
*/
if( conv->overflow || conv->underflow )
im_warn( "im_conv",
_( "%d overflows and %d underflows detected" ),
conv->overflow, conv->underflow );
return( 0 );
}
static Conv *
conv_new( IMAGE *in, IMAGE *out, INTMASK *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;
conv->underflow = 0;
conv->overflow = 0;
if( im_add_close_callback( out,
(im_callback_fn) conv_close, conv, NULL ) ||
im_add_close_callback( out,
(im_callback_fn) conv_evalstart, conv, NULL ) ||
im_add_close_callback( out,
(im_callback_fn) conv_evalend, conv, NULL ) ||
!(conv->coeff = IM_ARRAY( out, ne, int )) ||
!(conv->mask = im_dup_imask( 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 pointers */
int underflow; /* Underflow/overflow counts */
int overflow;
int last_bpl; /* Avoid recalcing offsets, if we can */
} ConvSequence;
/* Free a sequence value.
*/
static int
conv_stop( void *vseq, void *a, void *b )
{
ConvSequence *seq = (ConvSequence *) vseq;
Conv *conv = (Conv *) b;
/* Add local under/over counts to global counts.
*/
conv->overflow += seq->overflow;
conv->underflow += seq->underflow;
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;
seq->underflow = 0;
seq->overflow = 0;
seq->last_bpl = -1;
/* 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( seq );
}
#define INNER { \
sum += t[i] * p[i][x]; \
i += 1; \
}
/* INT and FLOAT inner loops.
*/
#define CONV_INT( TYPE, IM_CLIP ) { \
TYPE ** restrict p = (TYPE **) seq->pts; \
TYPE * restrict q = (TYPE *) IM_REGION_ADDR( or, le, y ); \
\
for( x = 0; x < sz; x++ ) { \
int sum; \
int i; \
\
sum = 0; \
i = 0; \
IM_UNROLL( conv->nnz, INNER ); \
\
sum = ((sum + rounding) / mask->scale) + mask->offset; \
\
IM_CLIP; \
\
q[x] = sum; \
} \
}
#define CONV_FLOAT( TYPE ) { \
TYPE ** restrict p = (TYPE **) seq->pts; \
TYPE * restrict q = (TYPE *) IM_REGION_ADDR( or, le, y ); \
\
for( x = 0; x < sz; x++ ) { \
double sum; \
int i; \
\
sum = 0; \
i = 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;
INTMASK *mask = conv->mask;
int * restrict t = conv->coeff;
/* You might think this should be (scale+1)/2, but then we'd be adding
* one for scale == 1.
*/
int rounding = mask->scale / 2;
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. Only do this if the bpl has changed since the
* previous im_prepare().
*/
if( seq->last_bpl != IM_REGION_LSKIP( ir ) ) {
seq->last_bpl = IM_REGION_LSKIP( ir );
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_INT( unsigned char, IM_CLIP_UCHAR( sum, seq ) );
break;
case IM_BANDFMT_CHAR:
CONV_INT( signed char, IM_CLIP_CHAR( sum, seq ) );
break;
case IM_BANDFMT_USHORT:
CONV_INT( unsigned short, IM_CLIP_USHORT( sum, seq ) );
break;
case IM_BANDFMT_SHORT:
CONV_INT( signed short, IM_CLIP_SHORT( sum, seq ) );
break;
case IM_BANDFMT_UINT:
CONV_INT( unsigned int, IM_CLIP_NONE( sum, seq ) );
break;
case IM_BANDFMT_INT:
CONV_INT( signed int, IM_CLIP_NONE( sum, seq ) );
break;
case IM_BANDFMT_FLOAT:
CONV_FLOAT( float );
break;
case IM_BANDFMT_DOUBLE:
CONV_FLOAT( double );
break;
default:
assert( 0 );
}
}
return( 0 );
}
int
im_conv_raw( IMAGE *in, IMAGE *out, INTMASK *mask )
{
Conv *conv;
/* Check parameters.
*/
if( !in || in->Coding != IM_CODING_NONE || im_iscomplex( in ) ) {
im_error( "im_conv", "%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_conv", "%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 );
out->Xsize -= mask->xsize - 1;
out->Ysize -= mask->ysize - 1;
if( out->Xsize <= 0 || out->Ysize <= 0 ) {
im_error( "im_conv", "%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_conv( IMAGE *in, IMAGE *out, INTMASK *mask )
{
IMAGE *t1 = im_open_local( out, "im_conv 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_conv_raw( t1, out, mask ) )
return( -1 );
out->Xoffset = 0;
out->Yoffset = 0;
return( 0 );
}
/* im__create_int_luts is not used in this file. We have to keep it for the use
* of other conv functions in this directory which have not yet been
* rewritten.
FIXME ... the only one left is im_convsub() which I'm sure no one
uses. Scrap this junk in the next version. Kill off the old gradient
and lindetect things too.
*/
/* Create multiplication luts for all non zero elements of the original mask;
* which is kept in buffer of length buffersize
* cnt is needed for freeing luts
*/
int
im__create_int_luts( int *buffer, int buffersize,
int **orig_luts, int **luts, int *cnt )
{
int *pbuffer;
int *buf1, *buf2, *pbuf1, *pbuf2;
int i, j;
int min, max;
int mark; /* used to mark the buffer mark = max+1 */
int counter; /* counts the no of unique elms in mask; returned in cnt*/
buf1 = (int*)calloc( (unsigned)buffersize, sizeof(int) );
buf2 = (int*)calloc( (unsigned)buffersize, sizeof(int) );
if ( ( buf1 == NULL ) || ( buf2 == NULL ) )
{
im_errormsg("im_create_int_luts: calloc failed (1)");
return( -1 );
}
pbuffer = buffer;
pbuf1 = buf1;
/* find max and copy mask to buf1 */
max = *pbuffer;
for ( i=0; i < buffersize; i++ )
{
if ( *pbuffer > max )
max = *pbuffer;
*pbuf1++ = *pbuffer++;
}
mark = max + 1;
pbuf1 = buf1;
pbuf2 = buf2;
counter = 0;
/* find a min at a time; put it into buf2 and mark all values of
* buf1 equal to found min, to INT_MAX
*/
for ( i=0; i < buffersize; i++ )
{
min = mark + 1; /* force min to be greater than mark */
pbuf1 = buf1;
/* find a min */
for ( j=0; j < buffersize; j++ )
{
if ( *pbuf1 < min )
min = *pbuf1;
pbuf1++;
}
if ( min == mark ) /* all min are found */
break;
*pbuf2++ = min;
counter++;
pbuf1 = buf1;
for ( j=0; j < buffersize; j++ ) /* mark values equal to min */
{
if ( *pbuf1 == min )
*pbuf1 = mark;
pbuf1++;
}
}
/* buf2 should keep now counter unique values of the mask, descending order
* Malloc counter luts and initialise them
*/
pbuf2 = buf2;
for ( i=0; i<counter; i++)
{
orig_luts[i] = (int*)calloc((unsigned)256, sizeof(int));
if (orig_luts[i] == NULL)
{
im_errormsg("im_create_int_luts: calloc failed (2)");
return( -1 );
}
for ( j=0; j<256; j++ )
*(orig_luts[i] + j) = j * (*pbuf2);
pbuf2++;
}
pbuffer = buffer;
for ( i=0; i<buffersize; i++ )
{
j = 0;
while ( 1 )
{
if ( *(buf2 + j) == *pbuffer )
{
luts[i] = orig_luts[j];
break;
}
j++;
}
pbuffer++;
}
/* free buf1, buf2 */
free((char*)buf1); free( (char*)buf2);
*cnt = counter;
return(0);
}