some tinkering

still not very quick

TODO

@@ -1,5 +1,3 @@
-- look for FCLIP / FABS use ... VIPS_ABS() on float type
-
 - write a shrinker that does two 1D shrinks, vertical and horizontal, with
   bicubic interpolation
 
@@ -7,6 +5,31 @@
 
   vips_resize() can use this, for the default path at least
 
+  try with affine vs. reduce in vips_resize ... on the laptop we see
+
+	affine
+	$ time vipsthumbnail wtc.tif -o x.tif -s 7000
+	real	0m2.325s
+	user	0m8.316s
+	sys	0m0.256s
+
+	reduce
+	$ time vipsthumbnail wtc.tif -o x.tif -s 7000
+	real	0m2.388s
+	user	0m8.544s
+	sys	0m0.244s
+
+  argh
+
+  reducev could be faster with the interpolator inlined ... we could pick a
+  set of masks and just run them along a set of input lines to make an output
+  line
+
+  reduceh ... not so clear, need to pick new masks every output pixel, might
+  not make much difference
+
+	
+
 - get some brightly coloured spots with nohalo / vsqbs on wobble.ws ... very
   odd, the interpolation shouldn't change between bands
 

libvips/resample/reduce.c

@@ -75,6 +75,32 @@ vips_reduce_build( VipsObject *object )
 	if( VIPS_OBJECT_CLASS( vips_reduce_parent_class )->build( object ) )
 		return( -1 );
 
+	/*
+	if( vips_reduceh( resample->in, &t[0], reduce->xshrink, 
+			"interpolate", reduce->interpolateh, NULL ) ||
+		vips_linecache( t[0], &t[1], 
+			"tile_height", 4,
+			NULL ) ||
+		vips_reducev( t[1], &t[2], reduce->yshrink, 
+			"interpolate", reduce->interpolatev, NULL ) ||
+		vips_image_write( t[2], resample->out ) )
+		return( -1 );
+	*/
+
+	/*
+	if( vips_reducev( resample->in, &t[0], reduce->yshrink, 
+			"interpolate", reduce->interpolatev, 
+			NULL ) ||
+		vips_linecache( t[0], &t[1], 
+			"tile_height", 4,
+			NULL ) ||
+		vips_reduceh( t[1], &t[2], reduce->xshrink, 
+			"interpolate", reduce->interpolateh, 
+			NULL ) ||
+		vips_image_write( t[2], resample->out ) )
+		return( -1 );
+	*/
+
 	if( vips_reducev( resample->in, &t[0], reduce->yshrink, 
 			"interpolate", reduce->interpolatev, NULL ) ||
 		vips_reduceh( t[0], &t[1], reduce->xshrink, 

libvips/resample/reduceh.c

@@ -184,10 +184,6 @@ vips_reduceh_build( VipsObject *object )
 		return( -1 );
 	in = t[1];
 
-	/* THINSTRIP will work, anything else will break seq mode. If you 
-	 * combine reduce with conv you'll need to use a line cache to maintain
-	 * sequentiality.
-	 */
 	if( vips_image_pipelinev( resample->out, 
 		VIPS_DEMAND_STYLE_THINSTRIP, in, NULL ) )
 		return( -1 );

libvips/resample/reducev.c

@@ -184,12 +184,8 @@ vips_reducev_build( VipsObject *object )
 		return( -1 );
 	in = t[1];
 
-	/* THINSTRIP will work, anything else will break seq mode. If you 
-	 * combine reduce with conv you'll need to use a line cache to maintain
-	 * sequentiality.
-	 */
 	if( vips_image_pipelinev( resample->out, 
-		VIPS_DEMAND_STYLE_THINSTRIP, in, NULL ) )
+		VIPS_DEMAND_STYLE_SMALLTILE, in, NULL ) )
 		return( -1 );
 
 	/* Size output. Note: we round the output width down!

libvips/resample/resize.c

@@ -230,12 +230,18 @@ vips_resize_build( VipsObject *object )
 		vips_info( class->nickname, "%s interpolation", nickname );
 	}
 
+	/*
 	if( vips_affine( in, &t[3], hresidual, 0, 0, vresidual, 
 		"interpolate", resize->interpolate,
 		"idx", resize->idx,
 		"idy", resize->idy,
 		NULL ) )  
 		return( -1 );
+	 */
+
+	if( vips_reduce( in, &t[3], 1.0 / hresidual, 1.0 / vresidual, NULL ) )  
+		return( -1 );
+
 	in = t[3];
 
 	/* If we are upsampling, don't sharpen. Also don't sharpen if we