/* Convert float to Radiance 32bit packed format

 *

 * 23/3/09

 *  - from im_rad2float and Radiance sources

 * 2/11/09

 *  - gtkdoc

 * 20/9/12

 *  - redo as a class

 * 13/12/12

 *  - tag as scRGB rather than XYZ

 */

/*

  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., 51 Franklin Street, Fifth Floor, Boston, MA

  02110-1301  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 <glib/gi18n-lib.h>

#include <stdio.h>

#include <math.h>

#include <vips/vips.h>

#include "pcolour.h"

/* 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])

/* assign a short color value */

static void

setcolr(COLR clr, double r, double g, double b)

{

  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.

 */

typedef VipsColourCode VipsFloat2rad;

typedef VipsColourCodeClass VipsFloat2radClass;

G_DEFINE_TYPE(VipsFloat2rad, vips_float2rad, VIPS_TYPE_COLOUR_CODE);

static void

vips_float2rad_line(VipsColour *colour, VipsPel *out, VipsPel **in, int width)

{

  COLOR *inp = (COLOR *) in[0];

  COLR *outbuf = (COLR *) out;

  while (width-- > 0) {

    setcolr(outbuf[0], inp[0][RED], inp[0][GRN], inp[0][BLU]);

    inp++;

    outbuf++;

  }

}

static void

vips_float2rad_class_init(VipsFloat2radClass *class)

{

  VipsObjectClass *object_class = (VipsObjectClass *) class;

  VipsColourClass *colour_class = VIPS_COLOUR_CLASS(class);

  object_class->nickname = "float2rad";

  object_class->description =

    _("transform float RGB to Radiance coding");

  colour_class->process_line = vips_float2rad_line;

}

static void

vips_float2rad_init(VipsFloat2rad *float2rad)

{

  VipsColour *colour = VIPS_COLOUR(float2rad);

  VipsColourCode *code = VIPS_COLOUR_CODE(float2rad);

  colour->coding = VIPS_CODING_RAD;

  colour->interpretation = VIPS_INTERPRETATION_scRGB;

  colour->format = VIPS_FORMAT_UCHAR;

  colour->input_bands = 3;

  colour->bands = 4;

  code->input_coding = VIPS_CODING_NONE;

  code->input_format = VIPS_FORMAT_FLOAT;

}

/**

 * vips_float2rad: (method)

 * @in: input image

 * @out: (out): output image

 * @...: %NULL-terminated list of optional named arguments

 *

 * Convert a three-band float image to Radiance 32-bit packed format.

 *

 * See also: vips_rad2float(), #VIPS_CODING_RAD, vips_LabQ2Lab().

 *

 * Returns: 0 on success, -1 on error.

 */

int

vips_float2rad(VipsImage *in, VipsImage **out, ...)

{

  va_list ap;

  int result;

  va_start(ap, out);

  result = vips_call_split("float2rad", ap, in, out);

  va_end(ap);

  return result;

}