diff --git a/TODO b/TODO
index e59eb872..31a7f8c5 100644
--- a/TODO
+++ b/TODO
@@ -1,76 +1,3 @@
-- butterworth item in filter menu in nip2 makes a mask, it doesn't filter the
-  image
-
-- butterworth highpass is wrong! actually makes a lowpass filter
-
-  $ ~/vips-7.26/bin/vips-7.26 vips im_create_fmask x2.v 32 32 2 42 0.5 0.5 0 0
-
-  is correct: a black circle on a white bg, with a white dot top left
-
-  2 because we have
-
-  	vips7compat.h:        IM_MASK_BUTTERWORTH_HIGHPASS = 2,
-
-  in vip8 this is
-
-  $ vips mask_butterworth x.v 32 32 42 0.5 0.5
-
-  generates a highpass filter, or 
-
-  $ vips mask_butterworth x.v 32 32 42 0.5 0.5 --reject
-
-  for a lowpass filter
-
-  doesn't match ideal! there we have --reject to make a highpass filter
-
-
-im_freq_mask has:
-
-	IM_MASK_IDEAL_HIGHPASS: 	0
-		if( vips_mask_ideal( 
-	IM_MASK_IDEAL_LOWPASS:		1
-		if( vips_mask_ideal( "reject", TRUE,  
-	IM_MASK_BUTTERWORTH_HIGHPASS:	2
-		if( vips_mask_butterworth( 
-	IM_MASK_BUTTERWORTH_LOWPASS:	3
-		if( vips_mask_butterworth( "reject", TRUE, 
-	IM_MASK_GAUSS_HIGHPASS:		4
-		if( vips_mask_gaussian(
-	IM_MASK_GAUSS_LOWPASS:		5
-		if( vips_mask_gaussian( "reject", TRUE,
-
-	IM_MASK_IDEAL_RINGPASS:		6
-		if( vips_mask_ideal_ring( 
-	IM_MASK_IDEAL_RINGREJECT:	7
-		if( vips_mask_ideal_ring(  "reject", TRUE,
-	IM_MASK_BUTTERWORTH_RINGPASS:	8
-		if( vips_mask_butterworth_ring( 
-	IM_MASK_BUTTERWORTH_RINGREJECT:	9
-		if( vips_mask_butterworth_ring(  "reject", TRUE,
-	IM_MASK_GAUSS_RINGPASS:		10
-		if( vips_mask_gaussian_ring(  
-	IM_MASK_GAUSS_RINGREJECT:	11
-		if( vips_mask_gaussian_ring(  "reject", TRUE,
-
-	IM_MASK_IDEAL_BANDPASS:		12
-		if( vips_mask_ideal_ring( 
-	IM_MASK_IDEAL_BANDREJECT:	13
-		if( vips_mask_ideal_ring(  "reject", TRUE,
-	IM_MASK_BUTTERWORTH_BANDPASS:	14
-		if( vips_mask_butterworth_ring( 
-	IM_MASK_BUTTERWORTH_BANDREJECT:	15
-		if( vips_mask_butterworth_ring(  "reject", TRUE,
-	IM_MASK_GAUSS_BANDPASS:		16
-		if( vips_mask_gaussian_ring(  
-	IM_MASK_GAUSS_BANDREJECT:	17
-		if( vips_mask_gaussian_ring(  "reject", TRUE,
-
-	IM_MASK_FRACTAL_FLT:		18
-		// not implemented
-
-
-
-
 
 - maxpos_avg seems to give variable results
 
@@ -92,6 +19,9 @@ $ vips max --size 10 spec/samples/wagon.v --x-array --y-array --out-array
   seems to be a race in maxpos_avg, it's still some Tom code, replace with a
   wrapper over vips_max()
 
+  hard to do, since vips_max() needs to be told in advance the number of maxes
+  it should search for
+