118 lines
2.6 KiB
C
118 lines
2.6 KiB
C
/* @(#) Extract the imaginary part of a complex image. Output is float or
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* @(#) double.
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* @(#)
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* @(#) int im_c2imag( in, out )
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* @(#) IMAGE *in, *out;
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* @(#)
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* @(#) All functions return 0 on success and -1 on error
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* @(#)
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*
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* Copyright: 1990, N. Dessipris.
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*
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* Author: Nicos Dessipris
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* Written on: 12/02/1990
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* Modified on : 09/05/1990
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* 21/12/94 JC
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* - im_c2amph() adapted to make im_c2real() and im_c2imag()
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*/
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/*
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This file is part of VIPS.
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VIPS is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/*
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These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
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*/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif /*HAVE_CONFIG_H*/
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#include <vips/intl.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include <vips/vips.h>
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#ifdef WITH_DMALLOC
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#include <dmalloc.h>
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#endif /*WITH_DMALLOC*/
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#define loop(TYPE) \
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{\
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TYPE *p = (TYPE *) in + 1;\
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TYPE *q = (TYPE *) out;\
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int x;\
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\
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for( x = 0; x < n; x++ ) {\
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double re = *p;\
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\
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p += 2;\
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*q++ = re;\
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}\
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}
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/* c2imag buffer processor.
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*/
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static void
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buffer_c2imag( void *in, void *out, int w, IMAGE *im )
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{
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int n = w * im->Bands;
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switch( im->BandFmt ) {
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case IM_BANDFMT_DPCOMPLEX: loop(double); break;
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case IM_BANDFMT_COMPLEX: loop(float); break;
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default:
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error_exit( "buffer_c2imag: internal error" );
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}
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}
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int
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im_c2imag( IMAGE *in, IMAGE *out )
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{
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if( in->Coding != IM_CODING_NONE || !im_iscomplex( in ) ) {
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im_errormsg( "im_c2imag: input should be uncoded complex" );
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return( -1 );
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}
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if( im_cp_desc( out, in ) )
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return( -1 );
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/* Output will be float or double.
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*/
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if( in->BandFmt == IM_BANDFMT_DPCOMPLEX ) {
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out->BandFmt = IM_BANDFMT_DOUBLE;
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out->Bbits = IM_BBITS_DOUBLE;
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}
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else {
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out->BandFmt = IM_BANDFMT_FLOAT;
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out->Bbits = IM_BBITS_FLOAT;
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}
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/* Do the processing.
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*/
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if( im_wrapone( in, out,
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(im_wrapone_fn) buffer_c2imag, in, NULL ) )
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return( -1 );
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return( 0 );
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}
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