libvips/libvips/conversion/black.c
2011-12-31 18:22:42 +00:00

184 lines
4.1 KiB
C

/* im_black.c
*
* Copyright: 1990, J. Cupitt
*
* Author: J. Cupitt
* Written on: 02/08/1990
* Modified on : 16/04/1991 by N. Dessipris to work on a line by line basis
* 15/8/94 JC
* - adapted for partials
* - ANSIfied
* - memory leaks fixed!
* 2/3/98 JC
* - IM_ANY added
* 18/1/09
* - gtkdoc
* 31/10/11
* - redo 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 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 <vips/intl.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <vips/vips.h>
#include <vips/internal.h>
#include <vips/debug.h>
#include "conversion.h"
typedef struct _VipsBlack {
VipsConversion parent_instance;
int width;
int height;
int bands;
} VipsBlack;
typedef VipsConversionClass VipsBlackClass;
G_DEFINE_TYPE( VipsBlack, vips_black, VIPS_TYPE_CONVERSION );
static int
vips_black_gen( VipsRegion *or, void *seq, void *a, void *b,
gboolean *stop )
{
vips_region_black( or );
return( 0 );
}
static int
vips_black_build( VipsObject *object )
{
VipsConversion *conversion = VIPS_CONVERSION( object );
VipsBlack *black = (VipsBlack *) object;
if( VIPS_OBJECT_CLASS( vips_black_parent_class )->build( object ) )
return( -1 );
vips_image_init_fields( conversion->out,
black->width, black->height, black->bands,
VIPS_FORMAT_UCHAR, VIPS_CODING_NONE,
black->bands == 1 ?
VIPS_INTERPRETATION_B_W : VIPS_INTERPRETATION_MULTIBAND,
1.0, 1.0 );
vips_demand_hint( conversion->out,
VIPS_DEMAND_STYLE_ANY, NULL );
if( vips_image_generate( conversion->out,
NULL, vips_black_gen, NULL, NULL, NULL ) )
return( -1 );
return( 0 );
}
static void
vips_black_class_init( VipsBlackClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
VIPS_DEBUG_MSG( "vips_black_class_init\n" );
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
vobject_class->nickname = "black";
vobject_class->description = _( "make a black image" );
vobject_class->build = vips_black_build;
VIPS_ARG_INT( class, "width", 4,
_( "Width" ),
_( "Image width in pixels" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsBlack, width ),
1, 1000000, 1 );
VIPS_ARG_INT( class, "height", 5,
_( "Height" ),
_( "Image height in pixels" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsBlack, height ),
1, 1000000, 1 );
VIPS_ARG_INT( class, "bands", 6,
_( "Bands" ),
_( "Number of bands in image" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsBlack, bands ),
1, 1000000, 1 );
}
static void
vips_black_init( VipsBlack *black )
{
black->bands = 1;
}
/**
* vips_black:
* @out: output image
* @width: output width
* @height: output height
* @...: %NULL-terminated list of optional named arguments
*
* Optional arguments:
*
* @bands: output bands
*
* Make a black unsigned char image of a specified size.
*
* See also: im_make_xy(), im_text(), im_gaussnoise().
*
* Returns: 0 on success, -1 on error
*/
int
vips_black( VipsImage **out, int width, int height, ... )
{
va_list ap;
int result;
va_start( ap, height );
result = vips_call_split( "black", ap, out, width, height );
va_end( ap );
return( result );
}