libvips/libsrc/colour/im_float2rad.c
2009-03-24 12:43:55 +00:00

207 lines
6.2 KiB
C

/* Convert float to Radiance 32bit packed format
* 23/3/09
* - from im_rad2float and Radiance sources
*/
/*
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
*/
/*
Sections of this file from Greg Ward and Radiance with kind
permission. The Radience copyright notice appears below.
*/
/* ====================================================================
* The Radiance Software License, Version 1.0
*
* Copyright (c) 1990 - 2009 The Regents of the University of California,
* through Lawrence Berkeley National Laboratory. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes Radiance software
* (http://radsite.lbl.gov/)
* developed by the Lawrence Berkeley National Laboratory
* (http://www.lbl.gov/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
* and "The Regents of the University of California" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact radiance@radsite.lbl.gov.
*
* 5. Products derived from this software may not be called "Radiance",
* nor may "Radiance" appear in their name, without prior written
* permission of Lawrence Berkeley National Laboratory.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of Lawrence Berkeley National Laboratory. For more
* information on Lawrence Berkeley National Laboratory, please see
* <http://www.lbl.gov/>.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <stdio.h>
#include <math.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/* Begin copy-paste from Radiance sources.
*/
#define RED 0
#define GRN 1
#define BLU 2
#define CIEX 0 /* or, if input is XYZ... */
#define CIEY 1
#define CIEZ 2
#define EXP 3 /* exponent same for either format */
#define COLXS 128 /* excess used for exponent */
#define WHT 3 /* used for RGBPRIMS type */
#undef BYTE
#define BYTE unsigned char /* 8-bit unsigned integer */
typedef BYTE COLR[4]; /* red, green, blue (or X,Y,Z), exponent */
typedef float COLORV;
typedef COLORV COLOR[3]; /* red, green, blue (or X,Y,Z) */
#define copycolor(c1,c2) ((c1)[0]=(c2)[0],(c1)[1]=(c2)[1],(c1)[2]=(c2)[2])
static void
setcolr( COLR clr, double r, double g, double b ) /* assign a short color value */
{
double d;
int e;
d = r > g ? r : g;
if (b > d) d = b;
if (d <= 1e-32) {
clr[RED] = clr[GRN] = clr[BLU] = 0;
clr[EXP] = 0;
return;
}
d = frexp(d, &e) * 255.9999 / d;
if (r > 0.0)
clr[RED] = r * d;
else
clr[RED] = 0;
if (g > 0.0)
clr[GRN] = g * d;
else
clr[GRN] = 0;
if (b > 0.0)
clr[BLU] = b * d;
else
clr[BLU] = 0;
clr[EXP] = e + COLXS;
}
/* End copy-paste from Radiance sources.
*/
static void
float2rad( COLOR *inp, COLR *outbuf, int n )
{
while (n-- > 0) {
setcolr( outbuf[0], inp[0][RED], inp[0][GRN], inp[0][BLU] );
inp++;
outbuf++;
}
}
int
im_float2rad( IMAGE *in, IMAGE *out )
{
/* Must be 3-band float.
*/
if( in->Bands != 3 || in->BandFmt != IM_BANDFMT_FLOAT ||
in->Coding != IM_CODING_NONE ) {
im_error( "im_float2rad", "%s",
_( "not a 3-band float uncoded image" ) );
return( -1 );
}
if( im_cp_desc( out, in ) )
return( -1 );
out->Bands = 4;
out->BandFmt = IM_BANDFMT_UCHAR;
out->Bbits = im_bits_of_fmt( out->BandFmt );
if( im_wrapone( in, out,
(im_wrapone_fn) float2rad, NULL, NULL ) )
return( -1 );
return( 0 );
}