start rot45

libvips/conversion/rot.c

@@ -1,4 +1,4 @@
-/* im_rot90
+/* rotate by 0/90/180/270 degrees
  *
  * Copyright: 1991, N. Dessipris
  * Written on: 28/10/91

libvips/conversion/rot45.c

@@ -0,0 +1,268 @@
+/* 'lossless' 45 degree rot45ate ... odd-sized square images only
+ *
+ * Author: N. Dessipris (Copyright, N. Dessipris 1991)
+ * Written on: 08/05/1991
+ * Modified on: 28/05/1991
+ * 12/10/95 JC
+ *	- small revisions, needs rewriting really
+ * 7/8/96 JC
+ *	- absolutely foul desp code revised
+ *	- many bugs and mem leaks fixed
+ * 1/3/99 JC
+ *	- oops, fns were not preserving scale and offset
+ * 1/12/10
+ * 	- allow any size mask for the 90 degree rot45ates by using im_rot4590().
+ * 12/10/13
+ * 	- redone as a class from im_offsets45()
+ */
+
+/*
+
+    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 _VipsRot45 {
+	VipsConversion parent_instance;
+
+	/* The input image.
+	 */
+	VipsImage *in;
+
+	/* Rotate by ...
+	 */
+	VipsAngle45 angle;
+
+	/* Output memory buffer ... copy this to ->out.
+	 */
+	VipsImage *outbuf; 
+
+} VipsRot45;
+
+typedef VipsConversionClass VipsRot45Class;
+
+G_DEFINE_TYPE( VipsRot45, vips_rot45, VIPS_TYPE_CONVERSION );
+
+
+/* Creates the offsets to rotate by 45 degrees an odd size square mask 
+ */
+int *
+im_offsets45( int size )
+{
+	int temp;
+	int x, y;
+	int size2 = size * size;
+	int size_2 = size / 2;
+	int *pnt, *cpnt1, *cpnt2;
+
+	if( size%2 == 0 ) {
+		im_error( "im_offsets45", "%s", _( "size not odd" ) );
+		return( NULL );
+	}
+	if( !(pnt = IM_ARRAY( NULL, size2, int )) ) 
+		return( NULL );
+
+	/* point at the beginning and end of the buffer
+	 */
+	cpnt1 = pnt; cpnt2 = pnt + size2 - 1;
+
+	for( y = 0; y < size_2; y++ ) {
+		temp = (size_2 + y) * size;
+		*cpnt1++ = temp; 
+		*cpnt2-- = size2 - 1 - temp;
+
+		for( x = 0; x < y; x++ ) {
+			temp -= (size-1);
+			*cpnt1++ = temp; 
+			*cpnt2-- = size2 - 1 - temp;
+		}
+
+		for( x = 0; x < size_2 - y; x++ ) {
+			temp -= size;
+			*cpnt1++ = temp; 
+			*cpnt2-- = size2 - 1 - temp;
+		}
+
+		for( x = 0; x < size_2 - y; x++ ) {
+			temp++;
+			*cpnt1++ = temp; 
+			*cpnt2-- = size2 - 1 - temp;
+		}
+
+		for( x = 0; x < y; x++ ) {
+			temp -= ( size - 1 );
+			*cpnt1++ = temp; 
+			*cpnt2-- = size2 - 1 - temp;
+		}
+	}
+
+	/* the diagonal now 
+	 */
+	temp = size * (size - 1);
+	cpnt1 = pnt + size_2 * size;
+	for( x = 0; x < size; x++ ) {
+		*cpnt1++ = temp; 
+		temp -= (size-1);
+	}
+
+#ifdef PIM_RINT
+	temp = 0;
+	for( y = 0; y < size; y++ ) {
+		for( x = 0; x < size; x++ ) {
+			fprintf( stderr, "%4d", *(pnt+temp) );
+			temp++;
+		}
+		fprintf(stderr, "\n");
+	}
+	fprintf(stderr, "\n");
+#endif
+
+	return( pnt );
+}
+
+static void
+vips_rot45_45( VipsRot45 *rot45 )
+{
+	int x, y, i;
+
+
+}
+
+static int
+vips_rot45_build( VipsObject *object )
+{
+	VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( object );
+	VipsConversion *conversion = VIPS_CONVERSION( object );
+	VipsRot45 *rot45 = (VipsRot *) object;
+	VipsImage **t = (VipsImage **) vips_object_local_array( object, 1 );
+
+	if( VIPS_OBJECT_CLASS( vips_rot45_parent_class )->build( object ) )
+		return( -1 );
+
+	if( vips_check_oddsquare( class->nickname, rot45->in ) )
+		return( -1 ); 
+
+	if( rot45->angle == VIPS_ANGLE45_0 )
+		return( vips_image_write( rot45->in, conversion->out ) );
+
+	if( vips_image_wio_input( rot45->in ) )
+		return( -1 );
+
+	if( vips_image_copy_fields( conversion->out, rot45->in ) )
+		return( -1 );
+
+	switch( rot45->angle ) {
+	case VIPS_ANGLE45_45:
+		break;
+
+	default:
+		g_assert( 0 );
+
+		/* Keep -Wall happy.
+		 */
+		return( 0 );
+	}
+
+	return( 0 );
+}
+
+static void
+vips_rot45_class_init( VipsRot45Class *class )
+{
+	GObjectClass *gobject_class = G_OBJECT_CLASS( class );
+	VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
+
+	VIPS_DEBUG_MSG( "vips_rot45_class_init\n" );
+
+	gobject_class->set_property = vips_object_set_property;
+	gobject_class->get_property = vips_object_get_property;
+
+	vobject_class->nickname = "rot45";
+	vobject_class->description = _( "rotate an image" );
+	vobject_class->build = vips_rot45_build;
+
+	VIPS_ARG_IMAGE( class, "in", 1, 
+		_( "Input" ), 
+		_( "Input image" ),
+		VIPS_ARGUMENT_REQUIRED_INPUT,
+		G_STRUCT_OFFSET( VipsRot45, in ) );
+
+	VIPS_ARG_ENUM( class, "angle", 6, 
+		_( "Angle" ), 
+		_( "Angle to rotate image" ),
+		VIPS_ARGUMENT_REQUIRED_INPUT,
+		G_STRUCT_OFFSET( VipsRot45, angle ),
+		VIPS_TYPE_ANGLE45, VIPS_ANGLE_45 ); 
+}
+
+static void
+vips_rot45_init( VipsRot45 *rot45 )
+{
+}
+
+/**
+ * vips_rot45:
+ * @in: input image
+ * @out: output image
+ * @angle: rotation angle
+ * @...: %NULL-terminated list of optional named arguments
+ *
+ * Rotate @in by a multiple of 45 degrees. Odd-length sides and square images
+ * only. 
+ *
+ * See also: vips_rot().
+ *
+ * Returns: 0 on success, -1 on error
+ */
+int
+vips_rot45( VipsImage *in, VipsImage **out, VipsAngle angle, ... )
+{
+	va_list ap;
+	int result;
+
+	va_start( ap, angle );
+	result = vips_call_split( "rot45", ap, in, out, angle );
+	va_end( ap );
+
+	return( result );
+}

libvips/include/vips/error.h

@@ -83,6 +83,7 @@ int vips_check_8or16( const char *domain, VipsImage *im );
 int vips_check_u8or16orf( const char *domain, VipsImage *im );
 int vips_check_format_same( const char *domain, VipsImage *im1, VipsImage *im2 );
 int vips_check_size_same( const char *domain, VipsImage *im1, VipsImage *im2 );
+int vips_check_oddsquare( const char *domain, VipsImage *im );
 int vips_check_vector_length( const char *domain, int n, int len );
 int vips_check_vector( const char *domain, int n, VipsImage *im );
 int vips_check_hist( const char *domain, VipsImage *im );

libvips/iofuncs/error.c

@@ -1012,6 +1012,32 @@ vips_check_size_same( const char *domain, VipsImage *im1, VipsImage *im2 )
 	return( 0 );
 }
 
+/**
+ * vips_check_oddsquare:
+ * @domain: the originating domain for the error message
+ * @im: image to check
+ *
+ * Check that the image is square and that the sides are odd. 
+ * If not, set an error message
+ * and return non-zero.
+ *
+ * See also: vips_error().
+ *
+ * Returns: 0 if OK, -1 otherwise.
+ */
+int
+vips_check_oddsquare( const char *domain, VipsImage *im )
+{
+	if( im->Xsize != im->Ysize || 
+		im->Xsize % 2 != 0 ) { 
+		vips_error( domain, 
+			"%s", _( "images must be odd and square" ) );
+		return( -1 );
+	}
+
+	return( 0 );
+}
+
 /**
  * vips_check_bands_same:
  * @domain: the originating domain for the error message