iclass_perimeter.c File Reference

Imagery library - functions for wx.iclass. More...

#include <stdlib.h>
#include <grass/vector.h>
#include <grass/raster.h>
#include <grass/glocale.h>
#include "iclass_local_proto.h"

Include dependency graph for iclass_perimeter.c:

Go to the source code of this file.

Macros
#define	extrema(x, y, z)   (((x < y) && (z < y)) || ((x > y) && (z > y)))
#define	non_extrema(x, y, z)   (((x < y) && (y < z)) || ((x > y) && (y > z)))

Functions
int	vector2perimeters (struct Map_info *Map, const char *layer_name, int category, IClass_perimeter_list *perimeters, struct Cell_head *band_region)
	Creates perimeters from vector areas of given category. More...
void	free_perimeters (IClass_perimeter_list *perimeters)
	Frees all perimeters in list of perimeters. More...
int	make_perimeter (struct line_pnts *points, IClass_perimeter *perimeter, struct Cell_head *band_region)
	Creates one perimeter from vector area. More...
int	edge2perimeter (IClass_perimeter *perimeter, int x0, int y0, int x1, int y1)
	Converts edge to cells. More...
void	perimeter_add_point (IClass_perimeter *perimeter, int x, int y)
	Adds point to perimeter. More...
int	edge_order (const void *aa, const void *bb)
	Determines points order during sorting. More...

Detailed Description

Imagery library - functions for wx.iclass.

Computation based on training areas for supervised classification. Based on i.class module (GRASS 6).

Vector map with training areas is used to determine corresponding cells by computing cells on area perimeter.

Copyright (C) 1999-2007, 2011 by the GRASS Development Team

This program is free software under the GNU General Public License (>=v2). Read the file COPYING that comes with GRASS for details.

Author

David Satnik, Central Washington University (original author)

Markus Neteler <neteler itc.it> (i.class module)

Bernhard Reiter <bernhard intevation.de> (i.class module)

Brad Douglas <rez touchofmadness.com>(i.class module)

Glynn Clements <glynn gclements.plus.com> (i.class module)

Hamish Bowman <hamish_b yahoo.com> (i.class module)

Jan-Oliver Wagner <jan intevation.de> (i.class module)

Anna Kratochvilova <kratochanna gmail.com> (rewriting for wx.iclass)

Vaclav Petras <wenzeslaus gmail.com> (rewriting for wx.iclass)

Definition in file iclass_perimeter.c.

Macro Definition Documentation

extrema

#define extrema	(		x,
			y,
			z
	)		(((x < y) && (z < y)) || ((x > y) && (z > y)))

Definition at line 36 of file iclass_perimeter.c.

non_extrema

#define non_extrema	(		x,
			y,
			z
	)		(((x < y) && (y < z)) || ((x > y) && (y > z)))

Definition at line 37 of file iclass_perimeter.c.

Function Documentation

edge2perimeter()

int edge2perimeter	(	IClass_perimeter *	perimeter,
		int	x0,
		int	y0,
		int	x1,
		int	y1
	)

Converts edge to cells.

It rasterizes edge given by two vertices. Resterized points are added to perimeter.

Parameters

perimeter	perimeter
x0,y0	first edge point row and cell
x1,y1	second edge point row and cell

Returns

1 on success

0 on error

Definition at line 329 of file iclass_perimeter.c.

edge_order()

int edge_order	(	const void *	aa,
		const void *	bb
	)

Determines points order during sorting.

Parameters

aa	first IClass_point
bb	second IClass_point

Definition at line 382 of file iclass_perimeter.c.

free_perimeters()

void free_perimeters

(

IClass_perimeter_list *

perimeters

)

Frees all perimeters in list of perimeters.

It also frees list of perimeters itself.

Parameters

perimeters

list of perimeters

Definition at line 134 of file iclass_perimeter.c.

References G_debug(), and G_free().

Referenced by I_iclass_analysis(), and vector2perimeters().

make_perimeter()

int make_perimeter	(	struct line_pnts *	points,
		IClass_perimeter *	perimeter,
		struct Cell_head *	band_region
	)

Creates one perimeter from vector area.

Parameters

	points	list of vertices represting area
[out]	perimeter	perimeter
	band_region	region which determines perimeter cells

Returns

1 on success

0 on error

Definition at line 156 of file iclass_perimeter.c.

Referenced by vector2perimeters().

perimeter_add_point()

void perimeter_add_point	(	IClass_perimeter *	perimeter,
		int	x,
		int	y
	)

Adds point to perimeter.

perimeter has to have allocated space for points member.

Parameters

perimeter	perimeter
x,y	point row and cell

Definition at line 365 of file iclass_perimeter.c.

References G_debug(), x, and line_pnts::y.

vector2perimeters()

int vector2perimeters	(	struct Map_info *	Map,
		const char *	layer_name,
		int	category,
		IClass_perimeter_list *	perimeters,
		struct Cell_head *	band_region
	)

Creates perimeters from vector areas of given category.

Parameters

	Map	vector map
	layer_name	layer name (within vector map)
	category	vector category (cat column value)
[out]	perimeters	list of perimeters
	band_region	region which determines perimeter cells

Returns

number of areas of given cat

-1 on error

Definition at line 51 of file iclass_perimeter.c.

References _, free_perimeters(), G_calloc, G_debug(), G_warning(), make_perimeter(), Vect_area_alive(), Vect_destroy_line_struct(), Vect_get_area_cat(), Vect_get_area_points(), Vect_get_field_number(), Vect_get_num_areas(), and Vect_new_line_struct().

Referenced by I_iclass_analysis().