/* extract an area and/or a set of bands

 *

 * Copyright: 1990, J. Cupitt

 *

 * Author: J. Cupitt

 * Written on: 12/02/1990

 * Modified on: 4/6/92, J.Cupitt

 *  - speed up! why wasn't this done before? Why am I stupid?

 *  - layout, messages fixed

 * now extracts IM_CODING_LABQ to IM_CODING_LABQ file: K.Martinez 1/7/93

 * 2/7/93 JC

 *  - adapted for partial v2

 *  - ANSIfied

 * 7/7/93 JC

 *  - behaviour for IM_CODING_LABQ fixed

 *  - better messages

 * 7/10/94 JC

 *  - new IM_NEW()

 * 22/2/95 JC

 *  - new use of im_region_region()

 * 6/7/98 JC

 *  - im_extract_area() and im_extract_band() added

 * 11/7/01 JC

 *  - im_extract_band() now numbers from zero

 * 7/11/01 JC

 *  - oh what pain, im_extract now numbers bands from zero as well

 * 6/9/02 JC

 *  - zero xoff/yoff for extracted area

 * 14/4/04 JC

 *  - nope, -ve the origin

 * 17/7/04

 *  - added im_extract_bands(), remove many bands from image

 * 24/3/09

 *  - added IM_CODING_RAD support

 * 29/1/10

 *  - cleanups

 *  - gtkdoc

 * 26/10/11

 *  - redone as a class

 */

/*

  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

 */

/*

#define VIPS_DEBUG

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif /*HAVE_CONFIG_H*/

#include <glib/gi18n-lib.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <vips/vips.h>

#include <vips/internal.h>

#include <vips/debug.h>

#include "pconversion.h"

#include "bandary.h"

typedef struct _VipsExtractArea {

  VipsConversion parent_instance;

  /* The input image.

   */

  VipsImage *in;

  int left;

  int top;

  int width;

  int height;

} VipsExtractArea;

typedef VipsConversionClass VipsExtractAreaClass;

G_DEFINE_TYPE(VipsExtractArea, vips_extract_area, VIPS_TYPE_CONVERSION);

/* Extract an area. Can just use pointers.

 */

static int

vips_extract_area_gen(VipsRegion *out_region,

  void *seq, void *a, void *b, gboolean *stop)

{

  VipsRegion *ir = (VipsRegion *) seq;

  VipsExtractArea *extract = (VipsExtractArea *) b;

  VipsRect iarea;

  /* Ask for input we need. Translate from demand in or's space to

   * demand in ir's space.

   */

  iarea = out_region->valid;

  iarea.left += extract->left;

  iarea.top += extract->top;

  if (vips_region_prepare(ir, &iarea))

    return -1;

  /* Attach or to ir.

   */

  if (vips_region_region(out_region, ir,

      &out_region->valid, iarea.left, iarea.top))

    return -1;

  return 0;

}

static int

vips_extract_area_build(VipsObject *object)

{

  VipsObjectClass *class = VIPS_OBJECT_GET_CLASS(object);

  VipsConversion *conversion = VIPS_CONVERSION(object);

  VipsExtractArea *extract = (VipsExtractArea *) object;

  if (VIPS_OBJECT_CLASS(vips_extract_area_parent_class)->build(object))

    return -1;

  if (extract->left + extract->width > extract->in->Xsize ||

    extract->top + extract->height > extract->in->Ysize ||

    extract->left < 0 || extract->top < 0 ||

    extract->width <= 0 || extract->height <= 0) {

    vips_error(class->nickname, "%s", _("bad extract area"));

    return -1;

  }

  if (vips_image_pio_input(extract->in) ||

    vips_check_coding_known(class->nickname, extract->in))

    return -1;

  if (vips_image_pipelinev(conversion->out,

      VIPS_DEMAND_STYLE_THINSTRIP, extract->in, NULL))

    return -1;

  conversion->out->Xsize = extract->width;

  conversion->out->Ysize = extract->height;

  conversion->out->Xoffset = -extract->left;

  conversion->out->Yoffset = -extract->top;

  if (vips_image_generate(conversion->out,

      vips_start_one, vips_extract_area_gen, vips_stop_one,

      extract->in, extract))

    return -1;

  return 0;

}

static void

vips_extract_area_class_init(VipsExtractAreaClass *class)

{

  GObjectClass *gobject_class = G_OBJECT_CLASS(class);

  VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS(class);

  VipsOperationClass *operation_class = VIPS_OPERATION_CLASS(class);

  VIPS_DEBUG_MSG("vips_extract_area_class_init\n");

  gobject_class->set_property = vips_object_set_property;

  gobject_class->get_property = vips_object_get_property;

  vobject_class->nickname = "extract_area";

  vobject_class->description = _("extract an area from an image");

  vobject_class->build = vips_extract_area_build;

  operation_class->flags = VIPS_OPERATION_SEQUENTIAL;

  VIPS_ARG_IMAGE(class, "input", 1,

    _("Input"),

    _("Input image"),

    VIPS_ARGUMENT_REQUIRED_INPUT,

    G_STRUCT_OFFSET(VipsExtractArea, in));

  VIPS_ARG_INT(class, "left", 3,

    _("Left"),

    _("Left edge of extract area"),

    VIPS_ARGUMENT_REQUIRED_INPUT,

    G_STRUCT_OFFSET(VipsExtractArea, left),

    -VIPS_MAX_COORD, VIPS_MAX_COORD, 0);

  VIPS_ARG_INT(class, "top", 4,

    _("Top"),

    _("Top edge of extract area"),

    VIPS_ARGUMENT_REQUIRED_INPUT,

    G_STRUCT_OFFSET(VipsExtractArea, top),

    -VIPS_MAX_COORD, VIPS_MAX_COORD, 0);

  VIPS_ARG_INT(class, "width", 5,

    _("Width"),

    _("Width of extract area"),

    VIPS_ARGUMENT_REQUIRED_INPUT,

    G_STRUCT_OFFSET(VipsExtractArea, width),

    1, VIPS_MAX_COORD, 1);

  VIPS_ARG_INT(class, "height", 6,

    _("Height"),

    _("Height of extract area"),

    VIPS_ARGUMENT_REQUIRED_INPUT,

    G_STRUCT_OFFSET(VipsExtractArea, height),

    1, VIPS_MAX_COORD, 1);

}

#ifdef __EMSCRIPTEN__

static void

vips_crop_init_adapter(VipsExtractArea *extract, void *dummy)

{

  vips_extract_area_init(extract);

}

#endif

static void

vips_extract_area_init(VipsExtractArea *extract)

{

}

/**

 * vips_extract_area: (method)

 * @in: input image

 * @out: (out): output image

 * @left: left edge of area to extract

 * @top: top edge of area to extract

 * @width: width of area to extract

 * @height: height of area to extract

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

 *

 * Extract an area from an image. The area must fit within @in.

 *

 * See also: vips_extract_bands(), vips_smartcrop().

 *

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

 */

int

vips_extract_area(VipsImage *in, VipsImage **out,

  int left, int top, int width, int height, ...)

{

  va_list ap;

  int result;

  va_start(ap, height);

  result = vips_call_split("extract_area", ap, in, out,

    left, top, width, height);

  va_end(ap);

  return result;

}

/* A synonym for extract_area.

 */

GType

vips_crop_get_type(void)

{

  static gsize gtype_id = 0;

  if (g_once_init_enter(&gtype_id)) {

    GType new_type = g_type_register_static_simple(VIPS_TYPE_CONVERSION,

      g_intern_static_string("crop"),

      sizeof(VipsExtractAreaClass),

      (GClassInitFunc) (void (*)(void)) vips_extract_area_class_intern_init,

      sizeof(VipsExtractArea),

#ifdef __EMSCRIPTEN__

      (GInstanceInitFunc) vips_crop_init_adapter,

#else

      (GInstanceInitFunc) (void (*)(void)) vips_extract_area_init,

#endif

      (GTypeFlags) 0);

    g_once_init_leave(&gtype_id, new_type);

  }

  return (GType) gtype_id;

}

/**

 * vips_crop: (method)

 * @in: input image

 * @out: (out): output image

 * @left: left edge of area to extract

 * @top: top edge of area to extract

 * @width: width of area to extract

 * @height: height of area to extract

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

 *

 * A synonym for vips_extract_area().

 *

 * See also: vips_extract_bands(), vips_smartcrop().

 *

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

 */

int

vips_crop(VipsImage *in, VipsImage **out,

  int left, int top, int width, int height, ...)

{

  va_list ap;

  int result;

  va_start(ap, height);

  result = vips_call_split("crop", ap, in, out,

    left, top, width, height);

  va_end(ap);

  return result;

}

typedef struct _VipsExtractBand {

  VipsBandary parent_instance;

  /* The input image.

   */

  VipsImage *in;

  int band;

  int n;

} VipsExtractBand;

typedef VipsBandaryClass VipsExtractBandClass;

G_DEFINE_TYPE(VipsExtractBand, vips_extract_band, VIPS_TYPE_BANDARY);

static void

vips_extract_band_buffer(VipsBandarySequence *seq,

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

{

  VipsBandary *bandary = seq->bandary;

  VipsConversion *conversion = (VipsConversion *) bandary;

  VipsExtractBand *extract = (VipsExtractBand *) bandary;

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

  int es = VIPS_IMAGE_SIZEOF_ELEMENT(im);

  int ips = VIPS_IMAGE_SIZEOF_PEL(im);

  const int ops = VIPS_IMAGE_SIZEOF_PEL(conversion->out);

  VipsPel *restrict p;

  VipsPel *restrict q;

  int x, z;

  p = in[0] + extract->band * es;

  q = out;

  if (ops == 1) {

    for (x = 0; x < width; x++) {

      q[x] = p[0];

      p += ips;

    }

  }

  else {

    for (x = 0; x < width; x++) {

      for (z = 0; z < ops; z++)

        q[z] = p[z];

      p += ips;

      q += ops;

    }

  }

}

static int

vips_extract_band_build(VipsObject *object)

{

  VipsObjectClass *class = VIPS_OBJECT_GET_CLASS(object);

  VipsBandary *bandary = (VipsBandary *) object;

  VipsExtractBand *extract = (VipsExtractBand *) object;

  if (extract->in) {

    int bands;

    vips_image_decode_predict(extract->in, &bands, NULL);

    bandary->n = 1;

    bandary->in = &extract->in;

    bandary->out_bands = extract->n;

    if (extract->band + extract->n > bands) {

      vips_error(class->nickname,

        "%s", _("bad extract band"));

      return -1;

    }

    if (extract->band == 0 &&

      extract->n == bands)

      return vips_bandary_copy(bandary);

  }

  if (VIPS_OBJECT_CLASS(vips_extract_band_parent_class)->build(object))

    return -1;

  return 0;

}

static void

vips_extract_band_class_init(VipsExtractBandClass *class)

{

  GObjectClass *gobject_class = G_OBJECT_CLASS(class);

  VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS(class);

  VipsBandaryClass *bandary_class = VIPS_BANDARY_CLASS(class);

  VIPS_DEBUG_MSG("vips_extract_band_class_init\n");

  gobject_class->set_property = vips_object_set_property;

  gobject_class->get_property = vips_object_get_property;

  vobject_class->nickname = "extract_band";

  vobject_class->description = _("extract band from an image");

  vobject_class->build = vips_extract_band_build;

  bandary_class->process_line = vips_extract_band_buffer;

  VIPS_ARG_IMAGE(class, "in", 1,

    _("Input"),

    _("Input image"),

    VIPS_ARGUMENT_REQUIRED_INPUT,

    G_STRUCT_OFFSET(VipsExtractBand, in));

  VIPS_ARG_INT(class, "band", 3,

    _("Band"),

    _("Band to extract"),

    VIPS_ARGUMENT_REQUIRED_INPUT,

    G_STRUCT_OFFSET(VipsExtractBand, band),

    0, VIPS_MAX_COORD, 0);

  VIPS_ARG_INT(class, "n", 4,

    _("n"),

    _("Number of bands to extract"),

    VIPS_ARGUMENT_OPTIONAL_INPUT,

    G_STRUCT_OFFSET(VipsExtractBand, n),

    1, VIPS_MAX_COORD, 1);

}

static void

vips_extract_band_init(VipsExtractBand *extract)

{

  extract->n = 1;

}

/**

 * vips_extract_band: (method)

 * @in: input image

 * @out: (out): output image

 * @band: index of first band to extract

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

 *

 * Optional arguments:

 *

 * * @n: number of bands to extract

 *

 * Extract a band or bands from an image. Extracting out of range is an error.

 *

 * @n defaults to 1.

 *

 * See also: vips_extract_area().

 *

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

 */

int

vips_extract_band(VipsImage *in, VipsImage **out, int band, ...)

{

  va_list ap;

  int result;

  va_start(ap, band);

  result = vips_call_split("extract_band", ap, in, out, band);

  va_end(ap);

  return result;

}