redo im_scale() as a class

ChangeLog

@@ -3,7 +3,7 @@
 - turn off caching for im_copy()/vips_copy(), we use copy to stop sharing, and
 it's cheap so caching doesn't help anyway
 - auto rshift down to 8 bits on save, if necessary
-- im_gaussnoise(), im_copy_file(), im_grid() redone as classes
+- im_gaussnoise(), im_copy_file(), im_grid(), im_scale() redone as classes
 - add --angle option to dzsave
 
 14/5/13 started 7.32.4

libvips/conversion/Makefile.am

@@ -29,7 +29,7 @@ libconversion_la_SOURCES = \
 	im_falsecolour.c \
 	im_msb.c \
 	grid.c \
-	im_scale.c \
+	scale.c \
 	im_scaleps.c \
 	im_subsample.c \
 	im_system.c \

libvips/conversion/conversion.c

@@ -127,6 +127,7 @@ vips_conversion_operation_init( void )
 	extern GType vips_bandbool_get_type( void ); 
 	extern GType vips_gaussnoise_get_type( void ); 
 	extern GType vips_grid_get_type( void ); 
+	extern GType vips_scale_get_type( void ); 
 
 	vips_copy_get_type();
 	vips_tile_cache_get_type(); 
@@ -151,6 +152,7 @@ vips_conversion_operation_init( void )
 	vips_bandbool_get_type(); 
 	vips_gaussnoise_get_type(); 
 	vips_grid_get_type(); 
+	vips_scale_get_type(); 
 }
 
 /* The common part of most binary conversion

libvips/conversion/copy.c

@@ -464,6 +464,7 @@ vips_copy( VipsImage *in, VipsImage **out, ... )
  * vips_copy_file:
  * @in: input image
  * @out: output image
+ * @...: %NULL-terminated list of optional named arguments
  *
  * A simple convenience function to copy an image to a file, then copy 
  * again to output. If the image is already a file, just copy straight 
@@ -477,7 +478,7 @@ vips_copy( VipsImage *in, VipsImage **out, ... )
  * Returns: 0 on success, -1 on error
  */
 int
-vips_copy_file( VipsImage *in, VipsImage **out )
+vips_copy_file( VipsImage *in, VipsImage **out, ... )
 {
 	VipsImage *file;
 

libvips/conversion/grid.c

@@ -1,4 +1,4 @@
-/* im_grid
+/* vips_grid
  *
  * 4/8/05
  * 7/9/05
@@ -6,6 +6,8 @@
  * 30/1/10
  * 	- gtkdoc
  * 	- small cleanups
+ * 30/5/13
+ * 	- redo as a class
  */
 
 /*

libvips/conversion/im_scale.c

@@ -1,100 +0,0 @@
-/* im_scale
- *
- * Author: John Cupitt
- * Written on: 22/4/93
- * Modified on: 
- * 30/6/93 JC
- *	- adapted for partial v2
- * 	- ANSI
- * 31/8/93 JC
- *	- calculation of offset now includes scale
- * 8/5/06
- * 	- set Type on output too
- * 16/10/06
- * 	- what? no, don't set Type, useful to be able to scale histograms, for
- * 	  example
- * 1/2/10
- * 	- gtkdoc
- */
-
-/*
-
-    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
-
- */
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif /*HAVE_CONFIG_H*/
-#include <vips/intl.h>
-
-#include <stdio.h>
-#include <stdlib.h>
-
-#include <vips/vips.h>
-
-/**
- * im_scale:
- * @in: input image
- * @out: output image
- *
- * Search the image for the maximum and minimum value, then return the image
- * as unsigned 8-bit, scaled so that the maximum value is 255 and the
- * minimum is zero.
- *
- * See also: im_clip2fmt(), im_scaleps().
- *
- * Returns: 0 on success, -1 on error
- */
-int 
-im_scale( IMAGE *in, IMAGE *out )
-{	
-	DOUBLEMASK *stats;
-	IMAGE *t = im_open_local( out, "im_scale:1", "p" );
-	double mx, mn;
-	double scale, offset;
-
-	/* Measure min and max, calculate transform.
-	 */
-	if( !t || !(stats = im_stats( in )) )
-		return( -1 );
-	mn = VIPS_MASK( stats, 0, 0 );
-	mx = VIPS_MASK( stats, 1, 0 );
-	im_free_dmask( stats );
-
-	if( mn == mx ) 
-		/* Range of zero: just return black.
-		 */
-		return( im_black( out, in->Xsize, in->Ysize, in->Bands ) );
-	scale = 255.0 / (mx - mn);
-	offset = -(mn * scale);
-
-	/* Transform!
-	 */
-	if( im_lintra( scale, in, offset, t ) ||
-		im_clip2fmt( t, out, IM_BANDFMT_UCHAR ) )
-		return( -1 );
-
-	return( 0 );
-}

libvips/conversion/scale.c

@@ -0,0 +1,165 @@
+/* im_scale
+ *
+ * Author: John Cupitt
+ * Written on: 22/4/93
+ * Modified on: 
+ * 30/6/93 JC
+ *	- adapted for partial v2
+ * 	- ANSI
+ * 31/8/93 JC
+ *	- calculation of offset now includes scale
+ * 8/5/06
+ * 	- set Type on output too
+ * 16/10/06
+ * 	- what? no, don't set Type, useful to be able to scale histograms, for
+ * 	  example
+ * 1/2/10
+ * 	- gtkdoc
+ * 30/5/13
+ * 	- redo as a class
+ */
+
+/*
+
+    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
+
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif /*HAVE_CONFIG_H*/
+#include <vips/intl.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <vips/vips.h>
+
+#include "conversion.h"
+
+typedef struct _VipsScale {
+	VipsConversion parent_instance;
+
+	VipsImage *in;
+
+} VipsScale;
+
+typedef VipsConversionClass VipsScaleClass;
+
+G_DEFINE_TYPE( VipsScale, vips_scale, VIPS_TYPE_CONVERSION );
+
+#define ARY( im, x, y ) *((double *) VIPS_IMAGE_ADDR( im, x, y ))
+
+static int
+vips_scale_build( VipsObject *object )
+{
+	VipsConversion *conversion = VIPS_CONVERSION( object );
+	VipsScale *scale = (VipsScale *) object;
+	VipsImage **t = (VipsImage **) vips_object_local_array( object, 7 );
+
+	double mx;
+	double mn;
+
+	if( VIPS_OBJECT_CLASS( vips_scale_parent_class )->build( object ) )
+		return( -1 );
+
+	if( vips_stats( scale->in, &t[0], NULL ) )
+		return( -1 );
+	mn = ARY( t[0], 0, 0 );
+	mx = ARY( t[0], 1, 0 );
+
+	if( mn == mx ) {
+		/* Range of zero: just return black.
+		 */
+		if( vips_black( &t[1], 
+			scale->in->Xsize, scale->in->Ysize, scale->in->Bands,
+			NULL ) ||
+			vips_image_write( t[1], conversion->out ) )
+			return( -1 );
+	}
+	else {
+		double f = 255.0 / (mx - mn);
+		double a = -(mn * f);
+
+		if( vips_linear1( scale->in, &t[2], f, a, NULL ) ||
+			vips_cast( t[2], &t[3], VIPS_FORMAT_UCHAR, NULL ) ||
+			vips_image_write( t[3], conversion->out ) )
+			return( -1 );
+	}
+
+	return( 0 );
+}
+
+static void
+vips_scale_class_init( VipsScaleClass *class )
+{
+	GObjectClass *gobject_class = G_OBJECT_CLASS( class );
+	VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
+
+	gobject_class->set_property = vips_object_set_property;
+	gobject_class->get_property = vips_object_get_property;
+
+	vobject_class->nickname = "scale";
+	vobject_class->description = _( "scale an image to uchar" );
+	vobject_class->build = vips_scale_build;
+
+	VIPS_ARG_IMAGE( class, "in", 1, 
+		_( "Input" ), 
+		_( "Input image" ),
+		VIPS_ARGUMENT_REQUIRED_INPUT,
+		G_STRUCT_OFFSET( VipsScale, in ) );
+
+}
+
+static void
+vips_scale_init( VipsScale *scale )
+{
+}
+
+/**
+ * vips_scale:
+ * @in: input image
+ * @out: output image
+ * @...: %NULL-terminated list of optional named arguments
+ *
+ * Search the image for the maximum and minimum value, then return the image
+ * as unsigned 8-bit, scaled so that the maximum value is 255 and the
+ * minimum is zero.
+ *
+ * See also: vips_cast().
+ *
+ * Returns: 0 on success, -1 on error
+ */
+int
+vips_scale( VipsImage *in, VipsImage **out, ... )
+{
+	va_list ap;
+	int result;
+
+	va_start( ap, out );
+	result = vips_call_split( "scale", ap, in, out );
+	va_end( ap );
+
+	return( result );
+}

libvips/deprecated/vips7compat.c

@@ -1511,6 +1511,22 @@ im_grid( VipsImage *in, VipsImage *out, int tile_height, int across, int down )
 	return( 0 );
 }
 
+int 
+im_scale( VipsImage *in, VipsImage *out )
+{
+	VipsImage *t;
+
+	if( vips_scale( in, &t, NULL ) )
+		return( -1 );
+	if( vips_image_write( t, out ) ) {
+		g_object_unref( t );
+		return( -1 );
+	}
+	g_object_unref( t );
+
+	return( 0 );
+}
+
 static int
 vips__math( VipsImage *in, VipsImage *out, VipsOperationMath math )
 {
@@ -3064,7 +3080,7 @@ im_copy_file( IMAGE *in, IMAGE *out )
 {
 	VipsImage *x;
 
-	if( vips_copy_file( in, &x ) )
+	if( vips_copy_file( in, &x, NULL ) )
 		return( -1 );
 	if( im_copy( x, out ) ) {
 		g_object_unref( x );

libvips/include/vips/conversion.h

@@ -168,7 +168,8 @@ int vips_sequential( VipsImage *in, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_cache( VipsImage *in, VipsImage **out, ... )
 	__attribute__((sentinel));
-int vips_copy_file( VipsImage *in, VipsImage **out );
+int vips_copy_file( VipsImage *in, VipsImage **out, ... )
+	__attribute__((sentinel));
 
 int vips_embed( VipsImage *in, VipsImage **out, 
 	int x, int y, int width, int height, ... )
@@ -214,6 +215,8 @@ int vips_cast_complex( VipsImage *in, VipsImage **out, ... )
 	__attribute__((sentinel));
 int vips_cast_dpcomplex( VipsImage *in, VipsImage **out, ... )
 	__attribute__((sentinel));
+int vips_scale( VipsImage *in, VipsImage **out, ... )
+	__attribute__((sentinel));
 
 int vips_bandjoin( VipsImage **in, VipsImage **out, int n, ... )
 	__attribute__((sentinel));
@@ -252,7 +255,6 @@ int vips_flatten( VipsImage *in, VipsImage **out, ... )
 
 
 
-int im_scale( VipsImage *in, VipsImage *out );
 int im_msb( VipsImage *in, VipsImage *out );
 int im_msb_band( VipsImage *in, VipsImage *out, int band );
 

libvips/include/vips/vips7compat.h

@@ -711,6 +711,7 @@ int im_gbandjoin( VipsImage **in, VipsImage *out, int n );
 int im_black( VipsImage *out, int x, int y, int bands );
 int im_gaussnoise( VipsImage *out, int x, int y, double mean, double sigma );
 int im_grid( VipsImage *in, VipsImage *out, int tile_height, int across, int down );
+int im_scale( VipsImage *in, VipsImage *out );
 
 int im_c2amph( VipsImage *in, VipsImage *out );
 int im_c2rect( VipsImage *in, VipsImage *out );

po/POTFILES.in

@@ -62,16 +62,15 @@ libvips/conversion/cast.c
 libvips/conversion/conversion.c
 libvips/conversion/flatten.c
 libvips/conversion/im_subsample.c
-libvips/conversion/im_grid.c
+libvips/conversion/grid.c
 libvips/conversion/extract.c
 libvips/conversion/bandjoin.c
 libvips/conversion/im_msb.c
-libvips/conversion/im_copy_file.c
 libvips/conversion/black.c
 libvips/conversion/bandbool.c
 libvips/conversion/copy.c
 libvips/conversion/rot.c
-libvips/conversion/im_scale.c
+libvips/conversion/scale.c
 libvips/conversion/replicate.c
 libvips/conversion/join.c
 libvips/conversion/im_text.c