libvips/libsrc/histograms_lut/im_histspec.c

218 lines
5.2 KiB
C

/* @(#) Creates a lut for transforming imagein (with histin) according to
* @(#) the pdf of imageref (with histref). The lut should have been set
* @(#) by a call to im_setbuf() or im_openout(). histin and histref
* @(#) should have been set by a call to im_mmapin() or they are buffer images
* @(#)
* @(#) Usage: int im_histspec(in, ref, out)
* @(#) IMAGE *histin, *histref, *out;
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
*
* Copyright: 1991, N. Dessipris.
*
* Author: Nicos Dessipris
* Written on: 19/07/1990
* Modified on: 26/03/1991
* 1/3/01 JC
* - bleurg! rewritten, now does 16 bits as well, bugs removed, faster,
* smaller
*/
/*
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 <assert.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/*
#define DEBUG
*/
/*
#define PIM_RINT
*/
/* Match two normalised cumulative histograms.
*/
static int
match( IMAGE *in, IMAGE *ref, IMAGE *out )
{
const int inpx = in->Xsize * in->Ysize;
const int refpx = ref->Xsize * ref->Ysize;
const int bands = in->Bands;
unsigned int *inbuf; /* in and ref, padded to same size */
unsigned int *refbuf;
unsigned int *outbuf; /* Always output as uint */
int px; /* Number of pixels */
int max; /* px * bands */
int i, j;
if( im_iocheck( in, out ) || im_iocheck( ref, out ) )
return( -1 );
if( in->Coding != IM_CODING_NONE || ref->Coding != IM_CODING_NONE ) {
im_errormsg( "im_histspec: not uncoded" );
return( -1 );
}
if( in->BandFmt != IM_BANDFMT_UINT ||
ref->BandFmt != IM_BANDFMT_UINT ) {
im_errormsg( "im_histspec: bad band format" );
return( -1 );
}
if( in->Bands != ref->Bands ) {
im_errormsg( "im_histspec: input histograms differ in "
"number of bands" );
return( -1 );
}
/* How big?
*/
if( inpx <= 256 && refpx <= 256 )
px = 256;
else if( inpx <= 65536 && refpx <= 65536 )
px = 65536;
else {
im_errormsg( "im_histspec: luts too large" );
return( -1 );
}
max = px * bands;
/* Unpack to equal sized buffers.
*/
inbuf = IM_ARRAY( out, max, unsigned int );
refbuf = IM_ARRAY( out, max, unsigned int );
outbuf = IM_ARRAY( out, max, unsigned int );
if( !inbuf || !refbuf || !outbuf )
return( -1 );
for( i = 0; i < inpx * bands; i++ )
inbuf[i] = ((unsigned int *)in->data)[i];
for( ; i < max; i++ )
inbuf[i] = 0;
for( i = 0; i < refpx * bands; i++ )
refbuf[i] = ((unsigned int *)ref->data)[i];
for( ; i < max; i++ )
refbuf[i] = 0;
for( j = 0; j < bands; j++ ) {
/* Track up refbuf[] with this.
*/
int ri = j;
int limit = max - bands;
for( i = j; i < max; i += bands ) {
unsigned int inv = inbuf[i];
for( ; ri < limit; ri += bands )
if( inv <= refbuf[ri] )
break;
if( ri < limit ) {
/* Simple rounding.
*/
double mid = refbuf[ri] +
refbuf[ri + bands] / 2.0;
if( inv < mid )
outbuf[i] = ri/bands;
else
outbuf[i] = ri/bands + 1;
}
else
outbuf[i] = refbuf[ri];
}
}
if( im_cp_descv( out, in, ref, NULL ) )
return( -1 );
out->Xsize = px;
out->Ysize = 1;
out->Type = IM_TYPE_HISTOGRAM;
if( im_setupout( out ) || im_writeline( 0, out, (PEL *) outbuf ) )
return( -1 );
return( 0 );
}
int
im_histspec( IMAGE *in, IMAGE *ref, IMAGE *out )
{
IMAGE *t1 = im_open_local( out, "im_histspec:1", "p" );
IMAGE *t2 = im_open_local( out, "im_histspec:2", "p" );
IMAGE *t3 = im_open_local( out, "im_histspec:3", "p" );
IMAGE *t4 = im_open_local( out, "im_histspec:4", "p" );
IMAGE *t5 = im_open_local( out, "im_histspec:5", "p" );
int px;
int fmt;
if( !t1 || !t2 || !t2 || !t4 || !t5 )
return( -1 );
if( !im_isuint( in ) || !im_isuint( ref ) ) {
im_errormsg( "im_histspec: input luts are not some unsigned "
"integer type" );
return( -1 );
}
/* Match hists.
*/
if( im_histeq( in, t1 ) || im_clip2ui( t1, t2 ) ||
im_histeq( ref, t3 ) || im_clip2ui( t3, t4 ) ||
match( t2, t4, t5 ) )
return( -1 );
/* Clip type down.
*/
px = t5->Xsize * t5->Ysize;
if( px <= 256 )
fmt = IM_BANDFMT_UCHAR;
else if( px <= 65536 )
fmt = IM_BANDFMT_USHORT;
else
fmt = IM_BANDFMT_UINT;
if( im_clip2fmt( t5, out, fmt ) )
return( -1 );
return( 0 );
}