387 lines
9.6 KiB
C
387 lines
9.6 KiB
C
/* horizontal shrink by an integer factor
|
|
*
|
|
* 30/10/15
|
|
* - from shrink.c
|
|
* 22/1/16
|
|
* - reorganise loops, 30% faster, vectorisable
|
|
* 15/8/16
|
|
* - rename xshrink -> hshrink for greater consistency
|
|
* 6/8/19
|
|
* - use a double sum buffer for int32 types
|
|
* 22/4/22 kleisauke
|
|
* - add @ceil option
|
|
*/
|
|
|
|
/*
|
|
|
|
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 DEBUG
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include <config.h>
|
|
#endif /*HAVE_CONFIG_H*/
|
|
#include <glib/gi18n-lib.h>
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <math.h>
|
|
|
|
#include <vips/vips.h>
|
|
#include <vips/debug.h>
|
|
#include <vips/internal.h>
|
|
|
|
#include "presample.h"
|
|
|
|
typedef struct _VipsShrinkh {
|
|
VipsResample parent_instance;
|
|
|
|
int hshrink; /* Shrink factor */
|
|
gboolean ceil; /* Round operation */
|
|
|
|
} VipsShrinkh;
|
|
|
|
typedef VipsResampleClass VipsShrinkhClass;
|
|
|
|
G_DEFINE_TYPE( VipsShrinkh, vips_shrinkh, VIPS_TYPE_RESAMPLE );
|
|
|
|
#define INNER( BANDS ) \
|
|
sum += p[x1]; \
|
|
x1 += BANDS;
|
|
|
|
/* Integer shrink.
|
|
*/
|
|
#define ISHRINK( ACC_TYPE, TYPE, BANDS ) { \
|
|
TYPE * restrict p = (TYPE *) in; \
|
|
TYPE * restrict q = (TYPE *) out; \
|
|
\
|
|
for( x = 0; x < width; x++ ) { \
|
|
for( b = 0; b < BANDS; b++ ) { \
|
|
ACC_TYPE sum; \
|
|
\
|
|
sum = 0; \
|
|
x1 = b; \
|
|
VIPS_UNROLL( shrink->hshrink, INNER( BANDS ) ); \
|
|
q[b] = (sum + shrink->hshrink / 2) / \
|
|
shrink->hshrink; \
|
|
} \
|
|
p += ne; \
|
|
q += BANDS; \
|
|
} \
|
|
}
|
|
|
|
/* Float shrink.
|
|
*/
|
|
#define FSHRINK( TYPE ) { \
|
|
TYPE * restrict p = (TYPE *) in; \
|
|
TYPE * restrict q = (TYPE *) out; \
|
|
\
|
|
for( x = 0; x < width; x++ ) { \
|
|
for( b = 0; b < bands; b++ ) { \
|
|
double sum; \
|
|
\
|
|
sum = 0.0; \
|
|
x1 = b; \
|
|
VIPS_UNROLL( shrink->hshrink, INNER( bands ) ); \
|
|
q[b] = sum / shrink->hshrink; \
|
|
} \
|
|
p += ne; \
|
|
q += bands; \
|
|
} \
|
|
}
|
|
|
|
/* Generate an area of @or. @ir is large enough.
|
|
*/
|
|
static void
|
|
vips_shrinkh_gen2( VipsShrinkh *shrink, VipsRegion *or, VipsRegion *ir,
|
|
int left, int top, int width )
|
|
{
|
|
VipsResample *resample = VIPS_RESAMPLE( shrink );
|
|
const int bands = resample->in->Bands *
|
|
(vips_band_format_iscomplex( resample->in->BandFmt ) ?
|
|
2 : 1);
|
|
const int ne = shrink->hshrink * bands;
|
|
VipsPel *out = VIPS_REGION_ADDR( or, left, top );
|
|
VipsPel *in = VIPS_REGION_ADDR( ir, left * shrink->hshrink, top );
|
|
|
|
int x;
|
|
int x1, b;
|
|
|
|
switch( resample->in->BandFmt ) {
|
|
case VIPS_FORMAT_UCHAR:
|
|
/* Generate a special path for 1, 3 and 4 band uchar data. The
|
|
* compiler will be able to vectorise these.
|
|
*
|
|
* Vectorisation doesn't help much for 16, 32-bit or float
|
|
* data, don't bother with them.
|
|
*/
|
|
switch( bands ) {
|
|
case 1:
|
|
ISHRINK( int, unsigned char, 1 ); break;
|
|
case 3:
|
|
ISHRINK( int, unsigned char, 3 ); break;
|
|
case 4:
|
|
ISHRINK( int, unsigned char, 4 ); break;
|
|
default:
|
|
ISHRINK( int, unsigned char, bands ); break;
|
|
}
|
|
break;
|
|
|
|
case VIPS_FORMAT_CHAR:
|
|
ISHRINK( int, char, bands ); break;
|
|
case VIPS_FORMAT_USHORT:
|
|
ISHRINK( int, unsigned short, bands ); break;
|
|
case VIPS_FORMAT_SHORT:
|
|
ISHRINK( int, short, bands ); break;
|
|
case VIPS_FORMAT_UINT:
|
|
ISHRINK( double, unsigned int, bands ); break;
|
|
case VIPS_FORMAT_INT:
|
|
ISHRINK( double, int, bands ); break;
|
|
case VIPS_FORMAT_FLOAT:
|
|
FSHRINK( float ); break;
|
|
case VIPS_FORMAT_DOUBLE:
|
|
FSHRINK( double ); break;
|
|
case VIPS_FORMAT_COMPLEX:
|
|
FSHRINK( float ); break;
|
|
case VIPS_FORMAT_DPCOMPLEX:
|
|
FSHRINK( double ); break;
|
|
|
|
default:
|
|
g_assert_not_reached();
|
|
}
|
|
}
|
|
|
|
static int
|
|
vips_shrinkh_gen( VipsRegion *or, void *seq,
|
|
void *a, void *b, gboolean *stop )
|
|
{
|
|
VipsShrinkh *shrink = (VipsShrinkh *) b;
|
|
VipsRegion *ir = (VipsRegion *) seq;
|
|
VipsRect *r = &or->valid;
|
|
|
|
int y;
|
|
|
|
/* How do we chunk up the image? We don't want to prepare the whole of
|
|
* the input region corresponding to *r since it could be huge.
|
|
*
|
|
* Request input a line at a time.
|
|
*
|
|
* We don't chunk horizontally. We want "vips shrink x.jpg b.jpg 100
|
|
* 100" to run sequentially. If we chunk horizontally, we will fetch
|
|
* 100x100 lines from the top of the image, then 100x100 100 lines
|
|
* down, etc. for each thread, then when they've finished, fetch
|
|
* 100x100, 100 pixels across from the top of the image. This will
|
|
* break sequentiality.
|
|
*/
|
|
|
|
#ifdef DEBUG
|
|
printf( "vips_shrinkh_gen: generating %d x %d at %d x %d\n",
|
|
r->width, r->height, r->left, r->top );
|
|
#endif /*DEBUG*/
|
|
|
|
for( y = 0; y < r->height; y ++ ) {
|
|
VipsRect s;
|
|
|
|
s.left = r->left * shrink->hshrink;
|
|
s.top = r->top + y;
|
|
s.width = r->width * shrink->hshrink;
|
|
s.height = 1;
|
|
#ifdef DEBUG
|
|
printf( "shrinkh_gen: requesting line %d\n", s.top );
|
|
#endif /*DEBUG*/
|
|
if( vips_region_prepare( ir, &s ) )
|
|
return( -1 );
|
|
|
|
VIPS_GATE_START( "vips_shrinkh_gen: work" );
|
|
|
|
vips_shrinkh_gen2( shrink, or, ir,
|
|
r->left, r->top + y, r->width );
|
|
|
|
VIPS_GATE_STOP( "vips_shrinkh_gen: work" );
|
|
}
|
|
|
|
VIPS_COUNT_PIXELS( or, "vips_shrinkh_gen" );
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
static int
|
|
vips_shrinkh_build( VipsObject *object )
|
|
{
|
|
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( object );
|
|
VipsResample *resample = VIPS_RESAMPLE( object );
|
|
VipsShrinkh *shrink = (VipsShrinkh *) object;
|
|
VipsImage **t = (VipsImage **)
|
|
vips_object_local_array( object, 2 );
|
|
|
|
VipsImage *in;
|
|
|
|
if( VIPS_OBJECT_CLASS( vips_shrinkh_parent_class )->build( object ) )
|
|
return( -1 );
|
|
|
|
in = resample->in;
|
|
|
|
if( shrink->hshrink < 1 ) {
|
|
vips_error( class->nickname,
|
|
"%s", _( "shrink factors should be >= 1" ) );
|
|
return( -1 );
|
|
}
|
|
|
|
if( shrink->hshrink == 1 )
|
|
return( vips_image_write( in, resample->out ) );
|
|
|
|
/* We need new pixels at the right so that we don't have small chunks
|
|
* to average down the right edge.
|
|
*/
|
|
if( vips_embed( in, &t[1],
|
|
0, 0,
|
|
in->Xsize + shrink->hshrink, in->Ysize,
|
|
"extend", VIPS_EXTEND_COPY,
|
|
NULL ) )
|
|
return( -1 );
|
|
in = t[1];
|
|
|
|
if( vips_image_pipelinev( resample->out,
|
|
VIPS_DEMAND_STYLE_THINSTRIP, in, NULL ) )
|
|
return( -1 );
|
|
|
|
/* Size output.
|
|
*
|
|
* Don't change xres/yres, leave that to the application layer. For
|
|
* example, vipsthumbnail knows the true shrink factor (including the
|
|
* fractional part), we just see the integer part here.
|
|
*/
|
|
resample->out->Xsize = shrink->ceil ?
|
|
VIPS_CEIL( (double) resample->in->Xsize / shrink->hshrink ) :
|
|
VIPS_ROUND_UINT(
|
|
(double) resample->in->Xsize / shrink->hshrink );
|
|
if( resample->out->Xsize <= 0 ) {
|
|
vips_error( class->nickname,
|
|
"%s", _( "image has shrunk to nothing" ) );
|
|
return( -1 );
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
printf( "vips_shrinkh_build: shrinking %d x %d image to %d x %d\n",
|
|
in->Xsize, in->Ysize,
|
|
resample->out->Xsize, resample->out->Ysize );
|
|
#endif /*DEBUG*/
|
|
|
|
if( vips_image_generate( resample->out,
|
|
vips_start_one, vips_shrinkh_gen, vips_stop_one,
|
|
in, shrink ) )
|
|
return( -1 );
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
static void
|
|
vips_shrinkh_class_init( VipsShrinkhClass *class )
|
|
{
|
|
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
|
|
VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
|
|
VipsOperationClass *operation_class = VIPS_OPERATION_CLASS( class );
|
|
|
|
VIPS_DEBUG_MSG( "vips_shrinkh_class_init\n" );
|
|
|
|
gobject_class->set_property = vips_object_set_property;
|
|
gobject_class->get_property = vips_object_get_property;
|
|
|
|
vobject_class->nickname = "shrinkh";
|
|
vobject_class->description = _( "shrink an image horizontally" );
|
|
vobject_class->build = vips_shrinkh_build;
|
|
|
|
operation_class->flags = VIPS_OPERATION_SEQUENTIAL;
|
|
|
|
VIPS_ARG_INT( class, "hshrink", 8,
|
|
_( "Hshrink" ),
|
|
_( "Horizontal shrink factor" ),
|
|
VIPS_ARGUMENT_REQUIRED_INPUT,
|
|
G_STRUCT_OFFSET( VipsShrinkh, hshrink ),
|
|
1, 1000000, 1 );
|
|
|
|
VIPS_ARG_BOOL( class, "ceil", 10,
|
|
_( "Ceil" ),
|
|
_( "Round-up output dimensions" ),
|
|
VIPS_ARGUMENT_OPTIONAL_INPUT,
|
|
G_STRUCT_OFFSET( VipsShrinkh, ceil ),
|
|
FALSE );
|
|
|
|
/* The old name .. now use h and v everywhere.
|
|
*/
|
|
VIPS_ARG_INT( class, "xshrink", 8,
|
|
_( "Xshrink" ),
|
|
_( "Horizontal shrink factor" ),
|
|
VIPS_ARGUMENT_REQUIRED_INPUT | VIPS_ARGUMENT_DEPRECATED,
|
|
G_STRUCT_OFFSET( VipsShrinkh, hshrink ),
|
|
1, 1000000, 1 );
|
|
|
|
}
|
|
|
|
static void
|
|
vips_shrinkh_init( VipsShrinkh *shrink )
|
|
{
|
|
}
|
|
|
|
/**
|
|
* vips_shrinkh: (method)
|
|
* @in: input image
|
|
* @out: (out): output image
|
|
* @hshrink: horizontal shrink
|
|
* @...: %NULL-terminated list of optional named arguments
|
|
*
|
|
* Optional arguments:
|
|
*
|
|
* * @ceil: round-up output dimensions
|
|
*
|
|
* Shrink @in horizontally by an integer factor. Each pixel in the output is
|
|
* the average of the corresponding line of @hshrink pixels in the input.
|
|
*
|
|
* This is a very low-level operation: see vips_resize() for a more
|
|
* convenient way to resize images.
|
|
*
|
|
* This operation does not change xres or yres. The image resolution needs to
|
|
* be updated by the application.
|
|
*
|
|
* See also: vips_shrinkv(), vips_shrink(), vips_resize(), vips_affine().
|
|
*
|
|
* Returns: 0 on success, -1 on error
|
|
*/
|
|
int
|
|
vips_shrinkh( VipsImage *in, VipsImage **out, int hshrink, ... )
|
|
{
|
|
va_list ap;
|
|
int result;
|
|
|
|
va_start( ap, hshrink );
|
|
result = vips_call_split( "shrinkh", ap, in, out, hshrink );
|
|
va_end( ap );
|
|
|
|
return( result );
|
|
}
|