started VipsLinear

This commit is contained in:
John Cupitt 2011-10-31 09:23:43 +00:00
parent c2efba5162
commit 55aab0236f

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libvips/arithmetic/linear.c Normal file
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/* im_lintra.c -- linear transform
*
* Copyright: 1990, N. Dessipris, based on im_powtra()
* Author: Nicos Dessipris
* Written on: 02/05/1990
* Modified on:
* 23/4/93 JC
* - adapted to work with partial images
* 1/7/93 JC
* - adapted for partial v2
* 7/10/94 JC
* - new IM_NEW()
* - more typedefs
* 9/2/95 JC
* - adapted for im_wrap...
* - operations on complex images now just transform the real channel
* 29/9/95 JC
* - complex was broken
* 15/4/97 JC
* - return(0) missing from generate, arrgh!
* 1/7/98 JC
* - im_lintra_vec added
* 3/8/02 JC
* - fall back to im_copy() for a == 1, b == 0
* 10/10/02 JC
* - auug, failing to multiply imag for complex! (thanks matt)
* 10/12/02 JC
* - removed im_copy() fallback ... meant that output format could change
* with value :-( very confusing
* 30/6/04
* - added 1 band image * n band vector case
* 8/12/06
* - add liboil support
* 9/9/09
* - gtkdoc comment, minor reformat
* 31/7/10
* - remove liboil
* 31/10/11
* - rework as a class
*/
/*
Copyright (C) 1991-2005 The National Gallery
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU 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 General Public License for more details.
You should have received a copy of the GNU 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 DEBUG
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#include "arithmetic.h"
#include "unary.h"
/**
* VipsLinear:
* @in: input #VipsImage
* @out: output #VipsImage
*
* For unsigned formats, this operation calculates (max - @in), eg. (255 -
* @in) for uchar. For signed and float formats, this operation calculates (-1
* * @in).
*
* See also: im_lintra().
*
* Returns: 0 on success, -1 on error
*/
typedef struct _VipsLinear {
VipsUnary parent_instance;
/* Our constants: multiply by a, add b.
*/
VipsArea *a;
VipsArea *b;
} VipsLinear;
typedef VipsUnaryClass VipsLinearClass;
G_DEFINE_TYPE( VipsLinear, vips_linear, VIPS_TYPE_UNARY );
static int
vips_linear_build( VipsObject *object )
{
VipsArithmetic *arithmetic = VIPS_ARITHMETIC( object );
VipsLinear *linear = (VipsLinear *) object;
if( VIPS_OBJECT_CLASS( vips_insert_parent_class )->build( object ) )
return( -1 );
if( vips_check_vector( "VipsLinear",
linear->a->n, arithmetic->in[0] ) ||
vips_check_vector( "VipsLinear",
linear->b->n, arithmetic->in[0] ) )
return( -1 );
how do we do this?? unary or arithmetic needs a bit of chopping about
if( in->Bands == 1 )
out->Bands = n;
bandalike a and b
return( 0 );
}
static void
vips_linear_buffer( VipsArithmetic *arithmetic, PEL *out, PEL **in, int width )
{
VipsImage *im = arithmetic->ready[0];
/* Complex just doubles the size.
*/
const int sz = width * vips_image_get_bands( im ) *
(vips_band_format_iscomplex( vips_image_get_format( im ) ) ?
2 : 1);
int x;
switch( vips_image_get_format( im ) ) {
case VIPS_FORMAT_UCHAR:
LOOP( unsigned char, UCHAR_MAX ); break;
case VIPS_FORMAT_CHAR:
LOOPN( signed char ); break;
case VIPS_FORMAT_USHORT:
LOOP( unsigned short, USHRT_MAX ); break;
case VIPS_FORMAT_SHORT:
LOOPN( signed short ); break;
case VIPS_FORMAT_UINT:
LOOP( unsigned int, UINT_MAX ); break;
case VIPS_FORMAT_INT:
LOOPN( signed int ); break;
case VIPS_FORMAT_FLOAT:
case VIPS_FORMAT_COMPLEX:
LOOPN( float ); break;
case VIPS_FORMAT_DOUBLE:
case VIPS_FORMAT_DPCOMPLEX:
LOOPN( double ); break;
default:
g_assert( 0 );
}
}
/* Save a bit of typing.
*/
#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
/* Format doesn't change with linear.
*/
static const VipsBandFormat vips_bandfmt_linear[10] = {
/* UC C US S UI I F X D DX */
F, F F, F, F, F, F, X, D, DX
};
static void
vips_invert_buffer( VipsArithmetic *arithmetic, PEL *out, PEL **in, int width )
{
VipsImage *im = arithmetic->ready[0];
/* Complex just doubles the size.
*/
const int sz = width * vips_image_get_bands( im ) *
(vips_band_format_iscomplex( vips_image_get_format( im ) ) ?
2 : 1);
int x;
switch( vips_image_get_format( im ) ) {
case VIPS_FORMAT_UCHAR:
LOOP( unsigned char, UCHAR_MAX ); break;
case VIPS_FORMAT_CHAR:
LOOPN( signed char ); break;
case VIPS_FORMAT_USHORT:
LOOP( unsigned short, USHRT_MAX ); break;
case VIPS_FORMAT_SHORT:
LOOPN( signed short ); break;
case VIPS_FORMAT_UINT:
LOOP( unsigned int, UINT_MAX ); break;
case VIPS_FORMAT_INT:
LOOPN( signed int ); break;
case VIPS_FORMAT_FLOAT:
case VIPS_FORMAT_COMPLEX:
LOOPN( float ); break;
case VIPS_FORMAT_DOUBLE:
case VIPS_FORMAT_DPCOMPLEX:
LOOPN( double ); break;
default:
g_assert( 0 );
}
}
static void
vips_linear_class_init( VipsLinearClass *class )
{
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsArithmeticClass *aclass = VIPS_ARITHMETIC_CLASS( class );
object_class->nickname = "linear";
object_class->description = _( "calculate (a * in + b)" );
object_class->build = vips_linear_build;
vips_arithmetic_set_format_table( aclass, vips_bandfmt_linear );
aclass->process_line = vips_linear_buffer;
VIPS_ARG_BOXED( class, "a", 4,
_( "a" ),
_( "Multiply by this" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsLinear, a ),
VIPS_TYPE_ARRAY_DOUBLE );
VIPS_ARG_BOXED( class, "b", 5,
_( "b" ),
_( "Add this" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsLinear, b ),
VIPS_TYPE_ARRAY_DOUBLE );
}
static void
vips_linear_init( VipsLinear *linear )
{
}
int
vips_linear( VipsImage *in, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_call_split( "linear", ap, in, out );
va_end( ap );
return( result );
}