diff --git a/libvips/convolution/im_aconv.c b/libvips/convolution/im_aconv.c
index 773aa777..8dd0b95f 100644
--- a/libvips/convolution/im_aconv.c
+++ b/libvips/convolution/im_aconv.c
@@ -1156,14 +1156,10 @@ im_aconv( IMAGE *in, IMAGE *out, DOUBLEMASK *mask, int n_layers, int cluster )
 	IMAGE *t[2];
 	Boxes *boxes;
 
-	printf( "optimising boxes ...\n" );
-
 	if( !(boxes = boxes_new( in, out, mask, n_layers, cluster )) ||
 		im_open_local_array( out, t, 2, "im_aconv", "p" ) )
 		return( -1 );
 
-	printf( "... done\n" );
-
 	/*
 	 */
 	if( im_embed( in, t[0], 1, mask->xsize / 2, mask->ysize / 2,