diff --git a/code/imageprocessing/as_improc_blockwising.m b/code/imageprocessing/as_improc_blockwising.m
index 230ac21..cc16dbc 100644
--- a/code/imageprocessing/as_improc_blockwising.m
+++ b/code/imageprocessing/as_improc_blockwising.m
@@ -24,7 +24,7 @@
     end
 end
 
-for (block=1:n_blocki*n_blockj)
+parfor(block=1:n_blocki*n_blockj,parforArg)
     j=1+(blocksize-overlap)*(mod(block-1,n_blockj));
     i=1+(blocksize-overlap)*(block-mod(block-1,n_blockj)-1)/n_blockj;