/* max of a pair of images

 *

 * 18/6/24

 *  - from add.c

 */

/*

  Copyright (C) 1991-2005 The National Gallery

  This library 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 2.1 of the License, or (at your option) any later version.

  This library 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 library; 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

 */

/*

#define DEBUG

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif /*HAVE_CONFIG_H*/

#include <glib/gi18n-lib.h>

#include <stdio.h>

#include <stdlib.h>

#include <math.h>

#include <vips/vips.h>

#include "binary.h"

typedef VipsBinary VipsMaxpair;

typedef VipsBinaryClass VipsMaxpairClass;

G_DEFINE_TYPE(VipsMaxpair, vips_maxpair, VIPS_TYPE_BINARY);

#define LOOP(TYPE) \

  { \

    TYPE *restrict left = (TYPE *) in[0]; \

    TYPE *restrict right = (TYPE *) in[1]; \

    TYPE *restrict q = (TYPE *) out; \

\

    for (int x = 0; x < sz; x++) \

      q[x] = VIPS_MAX(left[x], right[x]); \

  }

#define FLOOP(TYPE) \

  { \

    TYPE *restrict left = (TYPE *) in[0]; \

    TYPE *restrict right = (TYPE *) in[1]; \

    TYPE *restrict q = (TYPE *) out; \

\

    for (int x = 0; x < sz; x++) \

      q[x] = VIPS_FMAX(left[x], right[x]); \

  }

static void

maxpair_buffer(VipsArithmetic *arithmetic,

  VipsPel *out, VipsPel **in, int width)

{

  VipsImage *im = arithmetic->ready[0];

  int bands = vips_image_get_bands(im);

  VipsBandFormat format = vips_image_get_format(im);

  int sz = width * bands * (vips_band_format_iscomplex(format) ? 2 : 1);

  /* Maxpair all input types. Keep types here in sync with

   * vips_maxpair_format_table[] below.

   */

  switch (vips_image_get_format(im)) {

  case VIPS_FORMAT_UCHAR:

    LOOP(unsigned char);

    break;

  case VIPS_FORMAT_CHAR:

    LOOP(signed char);

    break;

  case VIPS_FORMAT_USHORT:

    LOOP(unsigned short);

    break;

  case VIPS_FORMAT_SHORT:

    LOOP(signed short);

    break;

  case VIPS_FORMAT_UINT:

    LOOP(unsigned int);

    break;

  case VIPS_FORMAT_INT:

    LOOP(signed int);

    break;

  case VIPS_FORMAT_FLOAT:

  case VIPS_FORMAT_COMPLEX:

    FLOOP(float);

    break;

  case VIPS_FORMAT_DOUBLE:

  case VIPS_FORMAT_DPCOMPLEX:

    FLOOP(double);

    break;

  default:

    g_assert_not_reached();

  }

}

#define UC VIPS_FORMAT_UCHAR

#define C VIPS_FORMAT_CHAR

#define US VIPS_FORMAT_USHORT

#define S VIPS_FORMAT_SHORT

#define UI VIPS_FORMAT_UINT

#define I VIPS_FORMAT_INT

#define F VIPS_FORMAT_FLOAT

#define X VIPS_FORMAT_COMPLEX

#define D VIPS_FORMAT_DOUBLE

#define DX VIPS_FORMAT_DPCOMPLEX

static const VipsBandFormat vips_maxpair_format_table[10] = {

  /* Band format:  UC  C  US  S  UI  I  F  X  D  DX */

  /* Promotion: */ UC, C, US, S, UI, I, F, X, D, DX

};

static void

vips_maxpair_class_init(VipsMaxpairClass *class)

{

  VipsObjectClass *object_class = (VipsObjectClass *) class;

  VipsArithmeticClass *aclass = VIPS_ARITHMETIC_CLASS(class);

  object_class->nickname = "maxpair";

  object_class->description = _("maximum of a pair of images");

  aclass->process_line = maxpair_buffer;

  vips_arithmetic_set_format_table(aclass, vips_maxpair_format_table);

}

static void

vips_maxpair_init(VipsMaxpair *maxpair)

{

}

/**

 * vips_maxpair:

 * @left: input image

 * @right: input image

 * @out: (out): output image

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

 *

 * For each pixel, pick the maximum of a pair of images.

 *

 * See also: vips_minpair().

 *

 * Returns: 0 on success, -1 on error

 */

int

vips_maxpair(VipsImage *left, VipsImage *right, VipsImage **out, ...)

{

  va_list ap;

  int result;

  va_start(ap, out);

  result = vips_call_split("maxpair", ap, left, right, out);

  va_end(ap);

  return result;

}