libvips/libsrc/convolution/rotmask.c

357 lines
8.0 KiB
C

/* @(#) Functions to create offsets for rotating square masks.
* @(#) Usage
* @(#) int *im_offsets45( size )
* @(#) int size;
* @(#)
* @(#) Returns an int pointer to valid offsets on sucess and -1 on error
* @(#)
*
* @(#) Usage
* @(#) int *im_offsets90( size )
* @(#) int size;
* @(#)
* @(#) Returns an int pointer to valid offsets on sucess and -1 on error
* @(#)
*
* @(#) Functions to rotate square masks
* @(#)
* @(#) Usage
* @(#) INTMASK *im_rotate_imask45( mask, name )
* @(#) INTMASK *mask;
* @(#)
* @(#) Returns an pointer to INTMASK which keeps the original mask rotated
* @(#) by 45 degrees clockwise.
* @(#) The filename member of the returned mask is set to name
* @(#)
* @(#) Usage
* @(#) DOUBLEMASK *im_rotate_dmask45( mask, name )
* @(#) DOUBLEMASK *mask;
* @(#)
* @(#) Returns an pointer to INTMASK which keeps the original mask rotated
* @(#) by 45 degrees clockwise.
* @(#) The filename member of the returned mask is set to name
* @(#)
* @(#) Usage
* @(#) INTMASK *im_rotate_imask90( mask, name )
* @(#) INTMASK *mask;
* @(#)
* @(#) Returns an pointer to INTMASK which keeps the original mask rotated
* @(#) by 90 degrees clockwise.
* @(#) The filename member of the returned mask is set to name
* @(#)
* @(#) Usage
* @(#) DOUBLEMASK *im_rotate_dmask90( mask, name )
* @(#) DOUBLEMASK *mask;
* @(#)
* @(#) Returns an pointer to DOUBLEMASK which keeps the original mask rotated
* @(#) by 90 degrees clockwise.
* @(#) The filename member of the returned mask is set to name
* @(#)
* @(#) Prints a mask. Used mainly for debugging purposes
* @(#)
* @(#) Usage
* @(#) void im_print_dmask( m )
* @(#) DOUBLEMASK *m;
* @(#)
* @(#) Usage
* @(#) void im_print_imask( m )
* @(#) INTMASK *m;
* @(#)
*
*
* Author: N. Dessipris (Copyright, N. Dessipris 1991)
* Written on: 08/05/1991
* Modified on: 28/05/1991
* 12/10/95 JC
* - small revisions, needs rewriting really
* 7/8/96 JC
* - absolutely foul desp code revised
* - many bugs and mem leaks fixed
* 1/3/99 JC
* - oops, fns were not preserving scale and offset
*/
/*
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
*/
/*
#define PIM_RINT 1
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Creates the offsets to rotate by 45 degrees an odd size square mask
*/
int *
im_offsets45( int size )
{
int temp;
int x, y;
int size2 = size * size;
int size_2 = size / 2;
int *pnt, *cpnt1, *cpnt2;
if( size%2 == 0 ) {
im_errormsg( "im_offsets45: size not odd" );
return( NULL );
}
if( !(pnt = IM_ARRAY( NULL, size2, int )) )
return( NULL );
/* point at the beginning and end of the buffer
*/
cpnt1 = pnt; cpnt2 = pnt + size2 - 1;
for( y = 0; y < size_2; y++ ) {
temp = (size_2 + y) * size;
*cpnt1++ = temp;
*cpnt2-- = size2 - 1 - temp;
for( x = 0; x < y; x++ ) {
temp -= (size-1);
*cpnt1++ = temp;
*cpnt2-- = size2 - 1 - temp;
}
for( x = 0; x < size_2 - y; x++ ) {
temp -= size;
*cpnt1++ = temp;
*cpnt2-- = size2 - 1 - temp;
}
for( x = 0; x < size_2 - y; x++ ) {
temp++;
*cpnt1++ = temp;
*cpnt2-- = size2 - 1 - temp;
}
for( x = 0; x < y; x++ ) {
temp -= ( size - 1 );
*cpnt1++ = temp;
*cpnt2-- = size2 - 1 - temp;
}
}
/* the diagonal now
*/
temp = size * (size - 1);
cpnt1 = pnt + size_2 * size;
for( x = 0; x < size; x++ ) {
*cpnt1++ = temp;
temp -= (size-1);
}
#ifdef PIM_RINT
temp = 0;
for( y = 0; y < size; y++ ) {
for( x = 0; x < size; x++ ) {
fprintf( stderr, "%4d", *(pnt+temp) );
temp++;
}
fprintf(stderr, "\n");
}
fprintf(stderr, "\n");
#endif
return( pnt );
}
/* Creates the offsets to rotate any mask by 90 degrees.
*/
int *
im_offsets90( int size )
{
int temp;
int x, y, k;
int *offsets;
if( !(offsets = IM_ARRAY( NULL, size*size, int )) )
return( NULL );
for( k = 0, y = 0; y < size; y++ ) {
temp = size * (size - 1) + y;
for( x = 0; x < size; x++, k++ ) {
offsets[k] = temp;
temp -= size;
}
}
return( offsets );
}
/* Tye pf offset-generating function.
*/
typedef int *(*offset_fn)( int );
/* Rotate a dmask with a set of offsets.
*/
static DOUBLEMASK *
rotdmask( offset_fn fn, DOUBLEMASK *m, const char *name )
{
DOUBLEMASK *out;
int size = m->xsize * m->ysize;
int *offsets;
int i;
if( m->xsize != m->ysize || (m->xsize % 2) == 0 ) {
im_errormsg( "im_rotate_*mask*: mask should "
"be square of even size" );
return( NULL );
}
if( !(offsets = fn( m->xsize )) )
return( NULL );
if( !(out = im_create_dmask( name, m->xsize, m->ysize )) ) {
im_free( offsets );
return( NULL );
}
out->scale = m->scale;
out->offset = m->offset;
for( i = 0; i < size; i++ )
out->coeff[i] = m->coeff[offsets[i]];
im_free( offsets );
return( out );
}
/* Rotate an imask with a set of offsets.
*/
static INTMASK *
rotimask( offset_fn fn, INTMASK *m, const char *name )
{
INTMASK *out;
int size = m->xsize * m->ysize;
int *offsets;
int i;
if( m->xsize != m->ysize || (m->xsize % 2) == 0 ) {
im_errormsg( "im_rotate_*mask*: mask should "
"be square of even size" );
return( NULL );
}
if( !(offsets = fn( m->xsize )) )
return( NULL );
if( !(out = im_create_imask( name, m->xsize, m->ysize )) ) {
im_free( offsets );
return( NULL );
}
out->scale = m->scale;
out->offset = m->offset;
for( i = 0; i < size; i++ )
out->coeff[i] = m->coeff[offsets[i]];
im_free( offsets );
return( out );
}
/* Returns a mask which is the argument mask rotated by 90 degrees. Filename
* of the returned mask is name.
*/
DOUBLEMASK *
im_rotate_dmask90( DOUBLEMASK *m, const char *name )
{
return( rotdmask( im_offsets90, m, name ) );
}
/* Returns a mask which is the argument mask rotated by 45 degrees. Filename
* of the returned mask is name.
*/
DOUBLEMASK *
im_rotate_dmask45( DOUBLEMASK *m, const char *name )
{
return( rotdmask( im_offsets45, m, name ) );
}
/* Returns a mask which is the argument mask rotated by 90 degrees. Filename
* of the returned mask is name.
*/
INTMASK *
im_rotate_imask90( INTMASK *m, const char *name )
{
return( rotimask( im_offsets90, m, name ) );
}
/* Returns a mask which is the argument mask rotated by 45 degrees. Filename
* of the returned mask is name.
*/
INTMASK *
im_rotate_imask45( INTMASK *m, const char *name )
{
return( rotimask( im_offsets45, m, name ) );
}
void
im_print_imask( INTMASK *m )
{
int i, j, k;
int *pm = m->coeff;
fprintf( stderr, " %s: %d %d %d %d\n",
m->filename, m->xsize, m->ysize, m->scale, m->offset );
for( k = 0, j = 0; j < m->ysize; j++ ) {
for( i = 0; i < m->xsize; i++, k++ )
fprintf( stderr, "%d\t", pm[k] );
fprintf( stderr, "\n" );
}
}
void
im_print_dmask( DOUBLEMASK *m )
{
int i, j, k;
double *pm = m->coeff;
fprintf( stderr, " %s: %d %d %f %f\n",
m->filename, m->xsize, m->ysize, m->scale, m->offset );
for( k = 0, j = 0; j < m->ysize; j++ ) {
for( i = 0; i < m->xsize; i++, k++ )
fprintf( stderr, "%f\t", pm[k] );
fprintf( stderr, "\n" );
}
}