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add find_trim

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compiles, not yet working
This commit is contained in:
John Cupitt 2017-07-25 14:52:45 +01:00
parent 42b04e48de
commit 1e7541bfb8
5 changed files with 262 additions and 0 deletions
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1
ChangeLog
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@ -10,6 +10,7 @@
- better prefix guessing on Windows, thanks tumagonx
- savers support a "page_height" option for multipage save
- rename 'disc' as 'memory' and default off
- add vips_find_trim(), search for non-background areas
12/6/17 started 8.5.7
- transform cmyk->rgb automatically on write if there's an embedded profile

1
libvips/arithmetic/Makefile.am
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@ -1,6 +1,7 @@
noinst_LTLIBRARIES = libarithmetic.la
libarithmetic_la_SOURCES = \
find_trim.c \
sum.c \
hough.c \
hough.h \

2
libvips/arithmetic/arithmetic.c
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@ -778,6 +778,7 @@ vips_arithmetic_operation_init( void )
extern GType vips_complex2_get_type( void );
extern GType vips_complexget_get_type( void );
extern GType vips_complexform_get_type( void );
extern GType vips_find_trim_get_type( void );
vips_add_get_type();
vips_sum_get_type();
@ -816,4 +817,5 @@ vips_arithmetic_operation_init( void )
vips_complex2_get_type();
vips_complexget_get_type();
vips_complexform_get_type();
vips_find_trim_get_type();
}

255
libvips/arithmetic/find_trim.c Normal file
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@ -0,0 +1,255 @@
/* return the bounding box of the non-border part of the image
*
* 26/7/17
* - from a ruby example
*/
/*
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 <vips/intl.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <vips/vips.h>
typedef struct _VipsFindTrim {
VipsOperation parent_instance;
VipsImage *in;
double threshold;
int left;
int top;
int width;
int height;
double *ones;
double *background;
int n;
} VipsFindTrim;
typedef VipsOperationClass VipsFindTrimClass;
G_DEFINE_TYPE( VipsFindTrim, vips_find_trim, VIPS_TYPE_OPERATION );
static void
vips_find_trim_finalize( GObject *gobject )
{
VipsFindTrim *find_trim = (VipsFindTrim *) gobject;
#ifdef DEBUG
printf( "vips_find_trim_finalize: " );
vips_object_print_name( VIPS_OBJECT( gobject ) );
printf( "\n" );
#endif /*DEBUG*/
VIPS_FREE( find_trim->background );
VIPS_FREE( find_trim->ones );
G_OBJECT_CLASS( vips_find_trim_parent_class )->finalize( gobject );
}
static int
vips_find_trim_build( VipsObject *object )
{
VipsFindTrim *find_trim = (VipsFindTrim *) object;
VipsImage **t = (VipsImage **) vips_object_local_array( object, 2 );
int i;
double *ones;
double d;
if( VIPS_OBJECT_CLASS( vips_find_trim_parent_class )->build( object ) )
return( -1 );
if( vips_image_decode( find_trim->in, &t[0] ) )
return( -1 );
/* Fetch pixel (0, 0) as the background value.
*/
if( vips_getpoint( t[0],
&find_trim->background, &find_trim->n,
0, 0, NULL ) )
return( -1 );
/* We want to subtract the bg.
*/
if( !(ones = VIPS_ARRAY( find_trim, find_trim->n, double )) )
return( -1 );
for( i = 0; i < find_trim->n; i++ ) {
ones[i] = 1.0;
find_trim->background[i] *= -1;
}
/* Smooth, find difference from bg, abs, threshold.
*/
if( vips_median( t[0], &t[1], 3, NULL ) ||
vips_linear( t[1], &t[2],
ones, find_trim->background, find_trim->n, NULL ) ||
vips_abs( t[2], &t[3], NULL ) ||
vips_more_const1( t[3], &t[4], find_trim->threshold, NULL ) )
return( -1 );
/* t[5] == column sums, t[6] == row sums.
*/
if( vips_project( t[4], &t[5], &t[6], NULL ) )
return( -1 );
/* t[8] == search column sums in from left.
*/
if( vips_profile( t[5], &t[7], &t[8], NULL ) ||
vips_avg( t[8], &d, NULL ) )
return( -1 );
find_trim->left = d;
if( vips_flip( t[5], &t[9], VIPS_DIRECTION_HORIZONTAL, NULL ) ||
vips_profile( t[9], &t[10], &t[11], NULL ) ||
vips_avg( t[11], &d, NULL ) )
return( -1 );
find_trim->width = (t[5]->Xsize - d) - find_trim->left;
/* t[8] == search column sums in from left.
*/
if( vips_profile( t[6], &t[12], &t[13], NULL ) ||
vips_avg( t[12], &d, NULL ) )
return( -1 );
find_trim->top = d;
if( vips_flip( t[6], &t[14], VIPS_DIRECTION_VERTICAL, NULL ) ||
vips_profile( t[14], &t[15], &t[16], NULL ) ||
vips_avg( t[15], &d, NULL ) )
return( -1 );
find_trim->height = (t[6]->Ysize - d) - find_trim->left;
return( 0 );
}
static void
vips_find_trim_class_init( VipsFindTrimClass *class )
{
GObjectClass *gobject_class = (GObjectClass *) class;
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsOperationClass *operation_class = VIPS_OPERATION_CLASS( class );
gobject_class->finalize = vips_find_trim_finalize;
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
object_class->nickname = "find_trim";
object_class->description = _( "search an image for non-edge areas" );
object_class->build = vips_find_trim_build;
operation_class->flags = VIPS_OPERATION_SEQUENTIAL;
VIPS_ARG_IMAGE( class, "in", 1,
_( "in" ),
_( "Image to find_trim" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsFindTrim, in ) );
VIPS_ARG_DOUBLE( class, "threshold", 2,
_( "Threshold" ),
_( "Object threshold" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsFindTrim, threshold ),
0, INFINITY, 10.0 );
VIPS_ARG_INT( class, "left", 5,
_( "Left" ),
_( "Left edge of image" ),
VIPS_ARGUMENT_REQUIRED_OUTPUT,
G_STRUCT_OFFSET( VipsFindTrim, left ),
1, VIPS_MAX_COORD, 1 );
VIPS_ARG_INT( class, "top", 11,
_( "Top" ),
_( "Top edge of extract area" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsFindTrim, top ),
0, VIPS_MAX_COORD, 0 );
VIPS_ARG_INT( class, "width", 12,
_( "Width" ),
_( "Width of extract area" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsFindTrim, width ),
1, VIPS_MAX_COORD, 1 );
VIPS_ARG_INT( class, "height", 13,
_( "Height" ),
_( "Height of extract area" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsFindTrim, height ),
1, VIPS_MAX_COORD, 1 );
}
static void
vips_find_trim_init( VipsFindTrim *find_trim )
{
find_trim->threshold = 10;
}
/**
* vips_find_trim:
* @in: image to find_trim
* @left: output left edge
* @top: output top edge
* @width: output width
* @height: output height
* @...: %NULL-terminated list of optional named arguments
*
* Optional arguments:
*
* * @threshold: background / object threshold
*
* See also: vips_extract_area(), vips_smartcrop().
*
* Returns: 0 on success, -1 on error
*/
int
vips_find_trim( VipsImage *in,
int *left, int *top, int *width, int *height, ... )
{
va_list ap;
int result;
va_start( ap, height );
result = vips_call_split( "find_trim", ap, in,
left, top, width, height );
va_end( ap );
return( result );
}

3
libvips/include/vips/arithmetic.h
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@ -384,6 +384,9 @@ int vips_stats( VipsImage *in, VipsImage **out, ... )
__attribute__((sentinel));
int vips_measure( VipsImage *in, VipsImage **out, int h, int v, ... )
__attribute__((sentinel));
int vips_find_trim( VipsImage *in,
int *left, int *top, int *width, int *height, ... )
__attribute__((sentinel));
int vips_getpoint( VipsImage *in, double **vector, int *n, int x, int y, ... )
__attribute__((sentinel));
int vips_hist_find( VipsImage *in, VipsImage **out, ... )