start moving im_shrink() to a class
This commit is contained in:
John Cupitt
parent
ff8ec789a0
commit
e9504c28f1
@ -5,6 +5,9 @@
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if ENABLE_CXX
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libresample_la_SOURCES = \
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resample.c \
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resample.h \
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shrink.c \
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im_affine.c \
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interpolate.c \
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im_shrink.c \
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@ -20,6 +23,9 @@ libresample_la_SOURCES = \
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else
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libresample_la_SOURCES = \
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resample.c \
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resample.h \
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shrink.c \
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im_affine.c \
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interpolate.c \
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im_shrink.c \
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117
libvips/resample/resample.c
Normal file
117
libvips/resample/resample.c
Normal file
@ -0,0 +1,117 @@
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/* base class for all resample operations
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*
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* properties:
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* - one in, one out
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* - not point-to-point
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* - size can change in any way
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* - bands, type, format etc. all fixed
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*/
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/*
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Copyright (C) 1991-2005 The National Gallery
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/*
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These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
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*/
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/*
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#define DEBUG
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*/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif /*HAVE_CONFIG_H*/
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#include <vips/intl.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include <vips/vips.h>
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#include <vips/internal.h>
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#include "resample.h"
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G_DEFINE_ABSTRACT_TYPE( VipsResample, vips_resample, VIPS_TYPE_OPERATION );
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static int
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vips_resample_build( VipsObject *object )
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{
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VipsResample *resample = VIPS_RESAMPLE( object );
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#ifdef DEBUG
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printf( "vips_resample_build: " );
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vips_object_print_name( object );
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printf( "\n" );
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#endif /*DEBUG*/
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g_object_set( resample, "out", vips_image_new(), NULL );
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if( VIPS_OBJECT_CLASS( vips_resample_parent_class )->build( object ) )
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return( -1 );
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return( 0 );
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}
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static void
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vips_resample_class_init( VipsResampleClass *class )
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{
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GObjectClass *gobject_class = G_OBJECT_CLASS( class );
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VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
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gobject_class->set_property = vips_object_set_property;
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gobject_class->get_property = vips_object_get_property;
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vobject_class->nickname = "resample";
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vobject_class->description = _( "resample operations" );
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vobject_class->build = vips_resample_build;
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VIPS_ARG_IMAGE( class, "in", 1,
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_( "Input" ),
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_( "Input image argument" ),
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VIPS_ARGUMENT_REQUIRED_INPUT,
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G_STRUCT_OFFSET( VipsResample, in ) );
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VIPS_ARG_IMAGE( class, "out", 2,
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_( "Output" ),
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_( "Output image" ),
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VIPS_ARGUMENT_REQUIRED_OUTPUT,
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G_STRUCT_OFFSET( VipsResample, out ) );
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}
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static void
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vips_resample_init( VipsResample *resample )
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{
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}
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/* Called from iofuncs to init all operations in this dir. Use a plugin system
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* instead?
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*/
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void
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vips_resample_operation_init( void )
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{
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extern GType vips_shrink_get_type( void );
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vips_shrink_get_type();
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}
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77
libvips/resample/resample.h
Normal file
77
libvips/resample/resample.h
Normal file
@ -0,0 +1,77 @@
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/* base class for all resample operations
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*/
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/*
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Copyright (C) 1991-2005 The National Gallery
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/*
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These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
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*/
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/* We don't want to get confused with the resample.h in include, put an
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* extra _ in there.
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*/
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#ifndef VIPS__RESAMPLE_H
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#define VIPS__RESAMPLE_H
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#ifdef __cplusplus
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extern "C" {
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#endif /*__cplusplus*/
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#define VIPS_TYPE_RESAMPLE (vips_resample_get_type())
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#define VIPS_RESAMPLE( obj ) \
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(G_TYPE_CHECK_INSTANCE_CAST( (obj), \
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VIPS_TYPE_RESAMPLE, VipsResample ))
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#define VIPS_RESAMPLE_CLASS( klass ) \
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(G_TYPE_CHECK_CLASS_CAST( (klass), \
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VIPS_TYPE_RESAMPLE, VipsResampleClass))
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#define VIPS_IS_RESAMPLE( obj ) \
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(G_TYPE_CHECK_INSTANCE_TYPE( (obj), VIPS_TYPE_RESAMPLE ))
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#define VIPS_IS_RESAMPLE_CLASS( klass ) \
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(G_TYPE_CHECK_CLASS_TYPE( (klass), VIPS_TYPE_RESAMPLE ))
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#define VIPS_RESAMPLE_GET_CLASS( obj ) \
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(G_TYPE_INSTANCE_GET_CLASS( (obj), \
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VIPS_TYPE_RESAMPLE, VipsResampleClass ))
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typedef struct _VipsResample {
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VipsOperation parent_instance;
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VipsImage *in;
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VipsImage *out;
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} VipsResample;
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typedef struct _VipsResampleClass {
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VipsOperationClass parent_class;
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} VipsResampleClass;
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GType vips_resample_get_type( void );
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#ifdef __cplusplus
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}
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#endif /*__cplusplus*/
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#endif /*VIPS__RESAMPLE_H*/
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411
libvips/resample/shrink.c
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411
libvips/resample/shrink.c
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@ -0,0 +1,411 @@
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/* shrink with a box filter
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*
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* Copyright: 1990, N. Dessipris.
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*
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* Authors: Nicos Dessipris and Kirk Martinez
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* Written on: 29/04/1991
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* Modified on: 2/11/92, 22/2/93 Kirk Martinez - Xres Yres & cleanup
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incredibly inefficient for box filters as LUTs are used instead of +
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Needs converting to a smoother filter: eg Gaussian! KM
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* 15/7/93 JC
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* - rewritten for partial v2
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* - ANSIfied
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* - now shrinks any non-complex type
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* - no longer cloned from im_convsub()
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* - could be much better! see km comments above
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* 3/8/93 JC
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* - rounding bug fixed
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* 11/1/94 JC
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* - problems with .000001 and round up/down ignored! Try shrink 3738
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* pixel image by 9.345000000001
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* 7/10/94 JC
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* - IM_NEW and IM_ARRAY added
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* - more typedef
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* 3/7/95 JC
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* - IM_CODING_LABQ handling added here
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* 20/12/08
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* - fall back to im_copy() for 1/1 shrink
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* 2/2/11
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* - gtk-doc
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* 10/2/12
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* - shrink in chunks to reduce peak memuse for large shrinks
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* - simpler
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* 12/6/12
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* - redone as a class
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* - special-case int shrinks
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*/
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/*
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This file is part of VIPS.
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VIPS is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/*
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These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
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*/
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/*
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#define DEBUG
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*/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif /*HAVE_CONFIG_H*/
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#include <vips/intl.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include <vips/vips.h>
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#include <vips/debug.h>
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#include "resample.h"
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typedef struct _VipsShrink {
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VipsResample parent_instance;
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double xshrink; /* Shrink factors */
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double yshrink;
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int mw; /* Size of area we average */
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int mh;
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int np; /* Number of pels we average */
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} VipsShrink;
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typedef VipsResampleClass VipsShrinkClass;
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G_DEFINE_TYPE( VipsShrink, vips_shrink, VIPS_TYPE_RESAMPLE );
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/* Our per-sequence parameter struct. Somewhere to sum band elements.
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*/
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typedef struct {
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VipsRegion *ir;
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VipsPel *sum;
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} VipsShrinkSequence;
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/* Free a sequence value.
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*/
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static int
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vips_shrink_stop( void *vseq, void *a, void *b )
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{
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VipsShrinkSequence *seq = (VipsShrinkSequence *) vseq;
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VIPS_FREEF( g_object_unref, seq->ir );
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return( 0 );
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}
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/* Make a sequence value.
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*/
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static void *
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vips_shrink_start( VipsImage *out, void *a, void *b )
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{
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VipsImage *in = (VipsImage *) a;
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VipsShrink *shrink = (VipsShrink *) b;
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VipsShrinkSequence *seq;
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if( !(seq = IM_NEW( out, VipsShrinkSequence )) )
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return( NULL );
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/* Init!
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*/
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seq->ir = vips_region_new( in );
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if( !(seq->sum = (VipsPel *) VIPS_ARRAY( out, in->Bands, double )) ) {
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vips_shrink_stop( seq, in, shrink );
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return( NULL );
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}
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return( (void *) seq );
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}
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/* Integer shrink.
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*/
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#define ISHRINK( TYPE ) { \
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int *sum = (int *) seq->sum; \
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TYPE *p = (TYPE *) in; \
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TYPE *q = (TYPE *) out; \
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\
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for( b = 0; b < bands; b++ ) \
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sum[b] = 0; \
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\
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for( y1 = 0; y1 < shrink->mh; y1++ ) { \
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for( i = 0, x1 = 0; x1 < shrink->mw; x1++ ) \
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for( b = 0; b < bands; b++, i++ ) \
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sum[b] += p[i]; \
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\
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p += ls; \
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} \
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\
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for( b = 0; b < bands; b++ ) \
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q[b] = (sum[b] + shrink->np / 2) / shrink->np; \
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}
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/* Float shrink.
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*/
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#define FSHRINK( TYPE ) { \
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double *sum = (double *) seq->sum; \
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TYPE *p = (TYPE *) in; \
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TYPE *q = (TYPE *) out; \
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\
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for( b = 0; b < bands; b++ ) \
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sum[b] = 0.0; \
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\
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for( y1 = 0; y1 < shrink->mh; y1++ ) { \
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for( i = 0, x1 = 0; x1 < shrink->mw; x1++ ) \
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for( b = 0; b < bands; b++, i++ ) \
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sum[b] += p[i]; \
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\
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p += ls; \
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} \
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\
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for( b = 0; b < bands; b++ ) \
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q[b] = sum[b] / shrink->np; \
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}
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/* Generate an area of @or. @ir is large enough.
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*/
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static void
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vips_shrink_gen2( VipsShrink *shrink, VipsShrinkSequence *seq,
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VipsRegion *or, VipsRegion *ir,
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int left, int top, int width, int height )
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{
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VipsResample *resample = VIPS_RESAMPLE( shrink );
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const int bands = resample->in->Bands;
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const int sizeof_pixel = VIPS_IMAGE_SIZEOF_PEL( resample->in );
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const int ls = VIPS_REGION_LSKIP( ir ) /
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VIPS_IMAGE_SIZEOF_ELEMENT( resample->in );
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int x, y, i;
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int x1, y1, b;
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for( y = 0; y < height; y++ ) {
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VipsPel *out = VIPS_REGION_ADDR( or, left, top + y );
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for( x = 0; x < width; x++ ) {
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int ix = (left + x) * shrink->xshrink;
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int iy = (top + y) * shrink->yshrink;
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VipsPel *in = VIPS_REGION_ADDR( ir, ix, iy );
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switch( resample->in->BandFmt ) {
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case VIPS_FORMAT_UCHAR:
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ISHRINK( unsigned char ); break;
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case VIPS_FORMAT_CHAR:
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ISHRINK( char ); break;
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case VIPS_FORMAT_USHORT:
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ISHRINK( unsigned short ); break;
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case VIPS_FORMAT_SHORT:
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ISHRINK( short ); break;
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case VIPS_FORMAT_UINT:
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ISHRINK( unsigned int ); break;
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case VIPS_FORMAT_INT:
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ISHRINK( int ); break;
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case VIPS_FORMAT_FLOAT:
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FSHRINK( float ); break;
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case VIPS_FORMAT_DOUBLE:
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FSHRINK( double ); break;
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default:
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g_assert( 0 );
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}
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out += sizeof_pixel;
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}
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}
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}
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static int
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vips_shrink_gen( VipsRegion *or, void *vseq, void *a, void *b, gboolean *stop )
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{
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VipsShrinkSequence *seq = (VipsShrinkSequence *) vseq;
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VipsShrink *shrink = (VipsShrink *) b;
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VipsRegion *ir = seq->ir;
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VipsRect *r = &or->valid;
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/* How do we chunk up the image? We don't want to prepare the whole of
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* the input region corresponding to *r since it could be huge.
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*
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* Each pixel of *r will depend on roughly mw x mh
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* pixels, so we walk *r in chunks which map to the tile size.
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*
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*/
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int xstep = 1 + VIPS__TILE_WIDTH / shrink->mw;
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int ystep = 1 + VIPS__TILE_HEIGHT / shrink->mh;
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int x, y;
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#ifdef DEBUG
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printf( "vips_shrink_gen: generating %d x %d at %d x %d\n",
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r->width, r->height, r->left, r->top );
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#endif /*DEBUG*/
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for( y = 0; y < r->height; y += ystep )
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for( x = 0; x < r->width; x += xstep ) {
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/* Clip the this rect against the demand size.
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*/
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int width = VIPS_MIN( xstep, r->width - x );
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int height = VIPS_MIN( ystep, r->height - y );
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VipsRect s;
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s.left = (r->left + x) * shrink->xshrink;
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s.top = (r->top + y) * shrink->yshrink;
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s.width = 1 + ceil( width * shrink->xshrink );
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s.height = 1 + ceil( height * shrink->yshrink );
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#ifdef DEBUG
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printf( "shrink_gen: requesting %d x %d at %d x %d\n",
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s.width, s.height, s.left, s.top );
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#endif /*DEBUG*/
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||||
if( vips_region_prepare( ir, &s ) )
|
||||
return( -1 );
|
||||
|
||||
vips_shrink_gen2( shrink, seq,
|
||||
or, ir,
|
||||
r->left + x, r->top + y, width, height );
|
||||
}
|
||||
|
||||
return( 0 );
|
||||
}
|
||||
|
||||
static int
|
||||
vips_shrink_build( VipsObject *object )
|
||||
{
|
||||
VipsResample *resample = VIPS_RESAMPLE( object );
|
||||
VipsShrink *shrink = (VipsShrink *) object;
|
||||
|
||||
if( VIPS_OBJECT_CLASS( vips_shrink_parent_class )->build( object ) )
|
||||
return( -1 );
|
||||
|
||||
shrink->mw = ceil( shrink->xshrink );
|
||||
shrink->mh = ceil( shrink->yshrink );
|
||||
shrink->np = shrink->mw * shrink->mh;
|
||||
|
||||
if( im_check_noncomplex( "VipsShrink", resample->in ) )
|
||||
return( -1 );
|
||||
|
||||
if( shrink->xshrink < 1.0 ||
|
||||
shrink->yshrink < 1.0 ) {
|
||||
vips_error( "VipsShrink",
|
||||
"%s", _( "shrink factors should be >= 1" ) );
|
||||
return( -1 );
|
||||
}
|
||||
|
||||
if( shrink->xshrink == 1.0 &&
|
||||
shrink->yshrink == 1.0 )
|
||||
return( vips_image_write( resample->in, resample->out ) );
|
||||
|
||||
if( vips_image_copy_fields( resample->out, resample->in ) )
|
||||
return( -1 );
|
||||
vips_demand_hint( resample->out,
|
||||
VIPS_DEMAND_STYLE_THINSTRIP, resample->in, NULL );
|
||||
|
||||
/* Size output. Note: we round the output width down!
|
||||
*/
|
||||
resample->out->Xsize = resample->in->Xsize / shrink->xshrink;
|
||||
resample->out->Ysize = resample->in->Ysize / shrink->yshrink;
|
||||
resample->out->Xres = resample->in->Xres / shrink->xshrink;
|
||||
resample->out->Yres = resample->in->Yres / shrink->yshrink;
|
||||
if( resample->out->Xsize <= 0 ||
|
||||
resample->out->Ysize <= 0 ) {
|
||||
vips_error( "VipsShrink",
|
||||
"%s", _( "image has shrunk to nothing" ) );
|
||||
return( -1 );
|
||||
}
|
||||
|
||||
if( vips_image_generate( resample->out,
|
||||
vips_shrink_start, vips_shrink_gen, vips_shrink_stop,
|
||||
resample->in, shrink ) )
|
||||
return( -1 );
|
||||
|
||||
return( 0 );
|
||||
}
|
||||
|
||||
static void
|
||||
vips_shrink_class_init( VipsShrinkClass *class )
|
||||
{
|
||||
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
|
||||
VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
|
||||
|
||||
VIPS_DEBUG_MSG( "vips_shrink_class_init\n" );
|
||||
|
||||
gobject_class->set_property = vips_object_set_property;
|
||||
gobject_class->get_property = vips_object_get_property;
|
||||
|
||||
vobject_class->nickname = "shrink";
|
||||
vobject_class->description = _( "shrink an image" );
|
||||
vobject_class->build = vips_shrink_build;
|
||||
|
||||
VIPS_ARG_DOUBLE( class, "xshrink", 9,
|
||||
_( "Xshrink" ),
|
||||
_( "Horizontal shrink factor" ),
|
||||
VIPS_ARGUMENT_REQUIRED_INPUT,
|
||||
G_STRUCT_OFFSET( VipsShrink, xshrink ),
|
||||
1.0, 1000000, 1 );
|
||||
|
||||
VIPS_ARG_DOUBLE( class, "yshrink", 9,
|
||||
_( "Yshrink" ),
|
||||
_( "Vertical shrink factor" ),
|
||||
VIPS_ARGUMENT_REQUIRED_INPUT,
|
||||
G_STRUCT_OFFSET( VipsShrink, yshrink ),
|
||||
1.0, 1000000, 1 );
|
||||
|
||||
}
|
||||
|
||||
static void
|
||||
vips_shrink_init( VipsShrink *shrink )
|
||||
{
|
||||
}
|
||||
|
||||
/**
|
||||
* vips_shrink:
|
||||
* @in: input image
|
||||
* @out: output image
|
||||
* @xshrink: horizontal shrink
|
||||
* @yshrink: vertical shrink
|
||||
*
|
||||
* Shrink @in by a pair of factors with a simple box filter.
|
||||
*
|
||||
* You will get aliasing for non-integer shrinks. In this case, shrink with
|
||||
* this function to the nearest integer size above the target shrink, then
|
||||
* downsample to the exact size with im_affinei() and your choice of
|
||||
* interpolator.
|
||||
*
|
||||
* im_rightshift_size() is faster for factors which are integer powers of two.
|
||||
*
|
||||
* See also: im_rightshift_size(), im_affinei().
|
||||
*
|
||||
* Returns: 0 on success, -1 on error
|
||||
*/
|
||||
int
|
||||
vips_shrink( VipsImage *in, VipsImage *out,
|
||||
double xshrink, double yshrink, ... )
|
||||
{
|
||||
va_list ap;
|
||||
int result;
|
||||
|
||||
va_start( ap, yshrink );
|
||||
result = vips_call_split( "shrink", ap, in, out, xshrink, yshrink );
|
||||
va_end( ap );
|
||||
|
||||
return( result );
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user