libvips/libsrc/inplace/smudge_area.c

320 lines
6.3 KiB
C

/* @(#) Smudge and smear a piece of image. Smudge is a low-pass filter,
* @(#) smear is an early version of smudge which contains a bug: it
* @(#) pushes pels to the left a little too. Looks cute though.
* @(#)
* @(#) r is the area to smudge/smear. Clipped against the image edges
* @(#) properly.
* @(#)
* @(#) int
* @(#) im_smudge( IMAGE *im, int ix, int iy, Rect *r )
* @(#)
* @(#) int
* @(#) im_smear( IMAGE *im, int ix, int iy, Rect *r )
* @(#)
*
* Copyright: J. Cupitt
* Written: 15/06/1992
* 22/7/93 JC
* - im_incheck() added
* 16/8/94 JC
* - im_incheck() changed to im_makerw()
* ? JC
* - im_makerw() changed to im_rwcheck()
* 5/12/06
* - im_invalidate() after paint
*/
/*
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 <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Smudge a section of an IMAGE. Smudge area r offset by x, y. Take average
* of pixels in 3x3 area surrounding current pixel for every pixel in r. We do
* not change the outermost pixels in the image, although we do read them.
*/
int
im_smudge( IMAGE *im, int ix, int iy, Rect *r )
{
int x, y, a, b, c;
int ba = im->Bands;
int el = ba * im->Xsize;
Rect area, image, clipped;
double total[ 256 ];
if( im_rwcheck( im ) )
return( -1 );
/* Don't do the margins.
*/
area = *r;
area.left += ix;
area.top += iy;
image.left = 0;
image.top = 0;
image.width = im->Xsize;
image.height = im->Ysize;
im_rect_marginadjust( &image, -1 );
im_rect_intersectrect( &area, &image, &clipped );
/* Any left?
*/
if( im_rect_isempty( &clipped ) )
return( 0 );
/* What we do for each type.
*/
#define SMUDGE(TYPE) \
for( y = clipped.top; y < clipped.top + clipped.height; y++ ) \
for( x = clipped.left; \
x < clipped.left + clipped.width; x++ ) { \
TYPE *to = (TYPE *) im->data + x * ba + y * el; \
TYPE *from = to - el - ba; \
TYPE *f; \
\
for( a = 0; a < ba; a++ ) \
total[a] = 0.0; \
\
for( a = 0; a < 3; a++ ) { \
f = from; \
for( b = 0; b < 3; b++ ) \
for( c = 0; c < ba; c++ ) \
total[c] += *f++; \
from += el; \
} \
\
for( a = 0; a < ba; a++ ) \
to[a] = (16 * (double) to[a] + total[a]) \
/ 25.0; \
}
/* Loop through the remaining pixels.
*/
switch( im->BandFmt ) {
case IM_BANDFMT_UCHAR:
SMUDGE(unsigned char);
break;
case IM_BANDFMT_CHAR:
SMUDGE(char);
break;
case IM_BANDFMT_USHORT:
SMUDGE(unsigned short);
break;
case IM_BANDFMT_SHORT:
SMUDGE(short);
break;
case IM_BANDFMT_UINT:
SMUDGE(unsigned int);
break;
case IM_BANDFMT_INT:
SMUDGE(int);
break;
case IM_BANDFMT_FLOAT:
SMUDGE(float);
break;
case IM_BANDFMT_DOUBLE:
SMUDGE(double);
break;
/* Do complex types too. Just treat as float and double, but with
* twice the number of bands.
*/
case IM_BANDFMT_COMPLEX:
/* Twice number of bands: double size and bands.
*/
ba *= 2;
el *= 2;
SMUDGE(float);
break;
case IM_BANDFMT_DPCOMPLEX:
/* Twice number of bands: double size and bands.
*/
ba *= 2;
el *= 2;
SMUDGE(double);
break;
default:
im_error( "im_smudge", _( "unknown band format" ) );
return( -1 );
}
im_invalidate( im );
return( 0 );
}
/* Smear a section of an IMAGE. As above, but shift it left a bit.
*/
int
im_smear( IMAGE *im, int ix, int iy, Rect *r )
{
int x, y, a, b, c;
int ba = im->Bands;
int el = ba * im->Xsize;
Rect area, image, clipped;
double total[ 256 ];
if( im_rwcheck( im ) )
return( -1 );
/* Don't do the margins.
*/
area = *r;
area.left += ix;
area.top += iy;
image.left = 0;
image.top = 0;
image.width = im->Xsize;
image.height = im->Ysize;
im_rect_marginadjust( &image, -1 );
image.left--;
im_rect_intersectrect( &area, &image, &clipped );
/* Any left?
*/
if( im_rect_isempty( &clipped ) )
return( 0 );
/* What we do for each type.
*/
#define SMEAR(TYPE) \
for( y = clipped.top; y < clipped.top + clipped.height; y++ ) \
for( x = clipped.left; \
x < clipped.left + clipped.width; x++ ) { \
TYPE *to = (TYPE *) im->data + x * ba + y * el; \
TYPE *from = to - el; \
TYPE *f; \
\
for( a = 0; a < ba; a++ ) \
total[a] = 0.0; \
\
for( a = 0; a < 3; a++ ) { \
f = from; \
for( b = 0; b < 3; b++ ) \
for( c = 0; c < ba; c++ ) \
total[c] += *f++; \
from += el; \
} \
\
for( a = 0; a < ba; a++ ) \
to[a] = (40 * (double) to[a+ba] + total[a]) \
/ 49.0; \
}
/* Loop through the remaining pixels.
*/
switch( im->BandFmt ) {
case IM_BANDFMT_UCHAR:
SMEAR(unsigned char);
break;
case IM_BANDFMT_CHAR:
SMEAR(char);
break;
case IM_BANDFMT_USHORT:
SMEAR(unsigned short);
break;
case IM_BANDFMT_SHORT:
SMEAR(short);
break;
case IM_BANDFMT_UINT:
SMEAR(unsigned int);
break;
case IM_BANDFMT_INT:
SMEAR(int);
break;
case IM_BANDFMT_FLOAT:
SMEAR(float);
break;
case IM_BANDFMT_DOUBLE:
SMEAR(double);
break;
/* Do complex types too. Just treat as float and double, but with
* twice the number of bands.
*/
case IM_BANDFMT_COMPLEX:
/* Twice number of bands: double size and bands.
*/
ba *= 2;
el *= 2;
SMEAR(float);
break;
case IM_BANDFMT_DPCOMPLEX:
/* Twice number of bands: double size and bands.
*/
ba *= 2;
el *= 2;
SMEAR(double);
break;
default:
im_error( "im_smear", _( "unknown band format" ) );
return( -1 );
}
im_invalidate( im );
return( 0 );
}