libvips/libvips/conversion/rot.c

488 lines
9.8 KiB
C

/* rotate by 0/90/180/270 degrees
*
* Copyright: 1991, N. Dessipris
* Written on: 28/10/91
* Updated on: 2/4/92, J.Cupitt
* bugs in im_la90rot fixed, now works for any type.
* 19/7/93 JC
* - IM_CODING_LABQ allowed now
* 15/11/94 JC
* - name changed
* - memory leaks fixed
* 8/2/95 JC
* - oops! memory allocation problem fixed
* 18/5/95 JC
* - IM_MAXLINES increased
* 13/8/96 JC
* - rewritten for partials
* 6/11/02 JC
* - speed-up ... replace memcpy() with a loop for small pixels
* 14/4/04
* - sets Xoffset / Yoffset
* 24/3/09
* - added IM_CODING_RAD support
* 1/2/10
* - cleanups
* - gtkdoc
* 4/11/11
* - rewrite as a class
* 7/3/17
* - added 90/180/270 convenience functions
*/
/*
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 <string.h>
#include <stdlib.h>
#include <vips/vips.h>
#include <vips/internal.h>
#include <vips/debug.h>
#include "pconversion.h"
typedef struct _VipsRot {
VipsConversion parent_instance;
/* The input image.
*/
VipsImage *in;
/* Rotate by ...
*/
VipsAngle angle;
} VipsRot;
typedef VipsConversionClass VipsRotClass;
G_DEFINE_TYPE( VipsRot, vips_rot, VIPS_TYPE_CONVERSION );
static int
vips_rot90_gen( VipsRegion *or, void *seq, void *a, void *b,
gboolean *stop )
{
VipsRegion *ir = (VipsRegion *) seq;
VipsImage *in = (VipsImage *) a;
/* Output area.
*/
VipsRect *r = &or->valid;
int le = r->left;
int ri = VIPS_RECT_RIGHT(r);
int to = r->top;
int bo = VIPS_RECT_BOTTOM(r);
int x, y, i;
/* Pixel geometry.
*/
int ps, ls;
/* Find the area of the input image we need.
*/
VipsRect need;
need.left = to;
need.top = in->Ysize - ri;
need.width = r->height;
need.height = r->width;
if( vips_region_prepare( ir, &need ) )
return( -1 );
/* Find PEL size and line skip for ir.
*/
ps = VIPS_IMAGE_SIZEOF_PEL( in );
ls = VIPS_REGION_LSKIP( ir );
/* Rotate the bit we now have.
*/
for( y = to; y < bo; y++ ) {
/* Start of this output line.
*/
VipsPel *q = VIPS_REGION_ADDR( or, le, y );
/* Corresponding position in ir.
*/
VipsPel *p = VIPS_REGION_ADDR( ir,
need.left + y - to,
need.top + need.height - 1 );
for( x = le; x < ri; x++ ) {
for( i = 0; i < ps; i++ )
q[i] = p[i];
q += ps;
p -= ls;
}
}
return( 0 );
}
static int
vips_rot180_gen( VipsRegion *or, void *seq, void *a, void *b,
gboolean *stop )
{
VipsRegion *ir = (VipsRegion *) seq;
VipsImage *in = (VipsImage *) a;
/* Output area.
*/
VipsRect *r = &or->valid;
int le = r->left;
int ri = VIPS_RECT_RIGHT(r);
int to = r->top;
int bo = VIPS_RECT_BOTTOM(r);
int x, y;
/* Pixel geometry.
*/
int ps;
/* Find the area of the input image we need.
*/
VipsRect need;
need.left = in->Xsize - ri;
need.top = in->Ysize - bo;
need.width = r->width;
need.height = r->height;
if( vips_region_prepare( ir, &need ) )
return( -1 );
/* Find PEL size and line skip for ir.
*/
ps = VIPS_IMAGE_SIZEOF_PEL( in );
/* Rotate the bit we now have.
*/
for( y = to; y < bo; y++ ) {
/* Start of this output line.
*/
VipsPel *q = VIPS_REGION_ADDR( or, le, y );
/* Corresponding position in ir.
*/
VipsPel *p = VIPS_REGION_ADDR( ir,
need.left + need.width - 1,
need.top + need.height - (y - to) - 1 );
/* Blap across!
*/
for( x = le; x < ri; x++ ) {
memcpy( q, p, ps );
q += ps;
p -= ps;
}
}
return( 0 );
}
static int
vips_rot270_gen( VipsRegion *or, void *seq, void *a, void *b,
gboolean *stop )
{
VipsRegion *ir = (VipsRegion *) seq;
VipsImage *in = (VipsImage *) a;
/* Output area.
*/
VipsRect *r = &or->valid;
int le = r->left;
int ri = VIPS_RECT_RIGHT(r);
int to = r->top;
int bo = VIPS_RECT_BOTTOM(r);
int x, y, i;
/* Pixel geometry.
*/
int ps, ls;
/* Find the area of the input image we need.
*/
VipsRect need;
need.left = in->Xsize - bo;
need.top = le;
need.width = r->height;
need.height = r->width;
if( vips_region_prepare( ir, &need ) )
return( -1 );
/* Find PEL size and line skip for ir.
*/
ps = VIPS_IMAGE_SIZEOF_PEL( in );
ls = VIPS_REGION_LSKIP( ir );
/* Rotate the bit we now have.
*/
for( y = to; y < bo; y++ ) {
/* Start of this output line.
*/
VipsPel *q = VIPS_REGION_ADDR( or, le, y );
/* Corresponding position in ir.
*/
VipsPel *p = VIPS_REGION_ADDR( ir,
need.left + need.width - (y - to) - 1,
need.top );
for( x = le; x < ri; x++ ) {
for( i = 0; i < ps; i++ )
q[i] = p[i];
q += ps;
p += ls;
}
}
return( 0 );
}
static int
vips_rot_build( VipsObject *object )
{
VipsConversion *conversion = VIPS_CONVERSION( object );
VipsRot *rot = (VipsRot *) object;
VipsGenerateFn generate_fn;
VipsDemandStyle hint;
if( VIPS_OBJECT_CLASS( vips_rot_parent_class )->build( object ) )
return( -1 );
if( rot->angle == VIPS_ANGLE_D0 )
return( vips_image_write( rot->in, conversion->out ) );
if( vips_image_pio_input( rot->in ) )
return( -1 );
hint = rot->angle == VIPS_ANGLE_D180 ?
VIPS_DEMAND_STYLE_THINSTRIP :
VIPS_DEMAND_STYLE_SMALLTILE;
if( vips_image_pipelinev( conversion->out, hint, rot->in, NULL ) )
return( -1 );
switch( rot->angle ) {
case VIPS_ANGLE_D90:
generate_fn = vips_rot90_gen;
conversion->out->Xsize = rot->in->Ysize;
conversion->out->Ysize = rot->in->Xsize;
conversion->out->Xoffset = rot->in->Ysize;
conversion->out->Yoffset = 0;
break;
case VIPS_ANGLE_D180:
generate_fn = vips_rot180_gen;
conversion->out->Xoffset = rot->in->Xsize;
conversion->out->Yoffset = rot->in->Ysize;
break;
case VIPS_ANGLE_D270:
generate_fn = vips_rot270_gen;
conversion->out->Xsize = rot->in->Ysize;
conversion->out->Ysize = rot->in->Xsize;
conversion->out->Xoffset = 0;
conversion->out->Yoffset = rot->in->Xsize;
break;
default:
g_assert_not_reached();
/* Stop compiler warnings.
*/
generate_fn = NULL;
}
if( vips_image_generate( conversion->out,
vips_start_one, generate_fn, vips_stop_one,
rot->in, rot ) )
return( -1 );
return( 0 );
}
static void
vips_rot_class_init( VipsRotClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
VIPS_DEBUG_MSG( "vips_rot_class_init\n" );
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
vobject_class->nickname = "rot";
vobject_class->description = _( "rotate an image" );
vobject_class->build = vips_rot_build;
VIPS_ARG_IMAGE( class, "in", 1,
_( "Input" ),
_( "Input image" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsRot, in ) );
VIPS_ARG_ENUM( class, "angle", 6,
_( "Angle" ),
_( "Angle to rotate image" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsRot, angle ),
VIPS_TYPE_ANGLE, VIPS_ANGLE_D90 );
}
static void
vips_rot_init( VipsRot *rot )
{
}
static int
vips_rotv( VipsImage *in, VipsImage **out, VipsAngle angle, va_list ap )
{
return( vips_call_split( "rot", ap, in, out, angle ) );
}
/**
* vips_rot: (method)
* @in: input image
* @out: (out): output image
* @angle: rotation angle
* @...: %NULL-terminated list of optional named arguments
*
* Rotate @in by a multiple of 90 degrees.
*
* Use vips_similarity() to rotate by an arbitary angle. vips_rot45() is
* useful for rotating convolution masks by 45 degrees.
*
* See also: vips_flip(), vips_similarity(), vips_rot45().
*
* Returns: 0 on success, -1 on error
*/
int
vips_rot( VipsImage *in, VipsImage **out, VipsAngle angle, ... )
{
va_list ap;
int result;
va_start( ap, angle );
result = vips_rotv( in, out, angle, ap );
va_end( ap );
return( result );
}
/**
* vips_rot90:
* @in: input image
* @out: output image
* @...: %NULL-terminated list of optional named arguments
*
* Rotate @in by 90 degress clockwise. A convenience function over vips_rot().
*
* See also: vips_rot().
*
* Returns: 0 on success, -1 on error
*/
int
vips_rot90( VipsImage *in, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_rotv( in, out, VIPS_ANGLE_D90, ap );
va_end( ap );
return( result );
}
/**
* vips_rot180: (method)
* @in: input image
* @out: (out): output image
* @...: %NULL-terminated list of optional named arguments
*
* Rotate @in by 180 degress. A convenience function over vips_rot().
*
* See also: vips_rot().
*
* Returns: 0 on success, -1 on error
*/
int
vips_rot180( VipsImage *in, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_rotv( in, out, VIPS_ANGLE_D180, ap );
va_end( ap );
return( result );
}
/**
* vips_rot270: (method)
* @in: input image
* @out: (out): output image
* @...: %NULL-terminated list of optional named arguments
*
* Rotate @in by 270 degress clockwise. A convenience function over vips_rot().
*
* See also: vips_rot().
*
* Returns: 0 on success, -1 on error
*/
int
vips_rot270( VipsImage *in, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_rotv( in, out, VIPS_ANGLE_D270, ap );
va_end( ap );
return( result );
}