152 lines
4.1 KiB
C
152 lines
4.1 KiB
C
/* @(#) Invert a UCHAR image. Very simple new-style VIPS routine. See
|
|
* @(#) im_exptra() for the next level of complexity. This function is not
|
|
* @(#) as quick as it could be - it is intended to be an example rather than
|
|
* @(#) to be useful. This should really be written with im_wrapone().
|
|
* @(#)
|
|
* @(#) int
|
|
* @(#) im_invert( IMAGE *in, IMAGE *out )
|
|
* @(#)
|
|
* @(#) All functions return 0 on success and -1 on error
|
|
* @(#)
|
|
*
|
|
* Copyright: 1990, N. Dessipris.
|
|
*
|
|
* Author: Nicos Dessipris
|
|
* Written on: 12/02/1990
|
|
* Modified on :
|
|
* 7/7/93 JC
|
|
* - memory leaks fixed
|
|
* - adapted for partial v2
|
|
* - ANSIfied
|
|
* 22/2/95 JC
|
|
* - tidied up again
|
|
*/
|
|
|
|
/*
|
|
|
|
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 <vips/vips.h>
|
|
|
|
#ifdef WITH_DMALLOC
|
|
#include <dmalloc.h>
|
|
#endif /*WITH_DMALLOC*/
|
|
|
|
/* Invert a REGION. We are given the REGION we should write to, the REGION we
|
|
* should use for input, and the IMAGE we are processing. On entry to
|
|
* invert_gen(), or points to the memory we should write to and ir is blank.
|
|
*/
|
|
static int
|
|
invert_gen( REGION *or, void *seq, void *a, void *b )
|
|
{
|
|
REGION *ir = (REGION *) seq;
|
|
|
|
/* Left, right, top and bottom for the output region.
|
|
*/
|
|
int le = or->valid.left;
|
|
int to = or->valid.top;
|
|
int bo = IM_RECT_BOTTOM( &or->valid );
|
|
|
|
int x, y;
|
|
|
|
/* Ask for the section of the input image we need to produce this
|
|
* section of the output image.
|
|
*/
|
|
if( im_prepare( ir, &or->valid ) )
|
|
return( -1 );
|
|
|
|
/* Loop over output, writing input.
|
|
*/
|
|
for( y = to; y < bo; y++ ) {
|
|
/* Point p and q at the start of the line of pels we must
|
|
* process this loop.
|
|
*/
|
|
PEL *p = (PEL *) IM_REGION_ADDR( ir, le, y );
|
|
PEL *q = (PEL *) IM_REGION_ADDR( or, le, y );
|
|
|
|
/* Loop along the line, processing pels.
|
|
* IM_REGION_N_ELEMENTS(region) gives
|
|
* the number of band elements across a region. By looping to
|
|
* IM_REGION_N_ELEMENTS() rather than ir->valid.width, we work
|
|
* for any number of bands.
|
|
*/
|
|
for( x = 0; x < IM_REGION_N_ELEMENTS( or ); x++ )
|
|
q[x] = 255 - p[x];
|
|
}
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
/* Invert IMAGE in to IMAGE out. Any number of bands, unsigned char pels
|
|
* only. See im_exptra() for an example of a VIPS function which can process
|
|
* any input image type.
|
|
*/
|
|
int
|
|
im_invert( IMAGE *in, IMAGE *out )
|
|
{
|
|
/* Check args.
|
|
*/
|
|
if( in->Coding != IM_CODING_NONE ) {
|
|
im_error( "im_invert", _( "not uncoded" ) );
|
|
return( -1 );
|
|
}
|
|
if( in->BandFmt != IM_BANDFMT_UCHAR ) {
|
|
im_error( "im_invert", _( "not UCHAR" ) );
|
|
return( -1 );
|
|
}
|
|
if( im_piocheck( in, out ) )
|
|
return( -1 );
|
|
|
|
/* Prepare the output header.
|
|
*/
|
|
if( im_cp_desc( out, in ) )
|
|
return( -1 );
|
|
|
|
/* Set demand hints. Like most one-to-one operations, we work best
|
|
* with long, thin strips.
|
|
*/
|
|
if( im_demand_hint( out, IM_THINSTRIP, in, NULL ) )
|
|
return( -1 );
|
|
|
|
/* Generate into out. im_start_one() and im_stop_one() are simple
|
|
* convenience functions provided by VIPS which do the necessary
|
|
* region creation and destruction for one-image-in
|
|
* style functions. See im_add(), im_start_many() and im_stop_many()
|
|
* for convenience functions for multiple inputs.
|
|
*/
|
|
if( im_generate( out,
|
|
im_start_one, invert_gen, im_stop_one, in, NULL ) )
|
|
return( -1 );
|
|
|
|
return( 0 );
|
|
}
|