sync

TODO

@@ -1,3 +1,31 @@
+- try
+
+	$ vips shrink Chicago.png x.png 228 228 --vips-progress
+	vips temp-4: 4 threads, 128 x 16 tiles, groups of 1280 scanlines
+	**
+	VIPS:ERROR:vipspng.c:431:png2vips_generate: assertion failed: (r->top
+	== read->y_pos)
+	$
+
+  but
+
+  	$ vipsthumbnail Chicago.png 
+	memory: high-water mark 66.96 MB
+	john@bambam ~/pics $ vipsthumbnail Chicago.png --verbose
+	thumbnailing Chicago.png
+	detected format as png
+	thumbnailing Chicago.png as ./tn_Chicago.jpg
+	integer shrink by 228
+	residual scale by 1
+	bilinear interpolation
+	sharpening thumbnail
+	memory: high-water mark 66.96 MB
+	$
+
+  is the extra cache that vipsthumbnail adds essential now? does that mean
+  that the mediawiki scalr can never work?
+
+
 - look at
 	
 	There is an order 1 algorithm for doing medians over boxes (truly O(1)