use Imports: instead of Depends:

diff --git a/DESCRIPTION b/DESCRIPTION
index 682c77046f91c58ff48add20eb67850247487710..cadc405f694216d30cb11bdb990b9354c3ca263f 100644 (file)
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -5,8 +5,9 @@ Version: 1.0
 Date: 2016-06-20
 Authors@R: person("Don","Armstrong",email="don@donarmstrong.com",role=c("aut","cre"))
 Maintainer: Don Armstrong <don@donarmstrong.com>
-Depends: Cairo, grid
-Recommends: pdftk
+Imports: Cairo, grid,
+    grDevices
+SystemRequirements: pdftk
 Description: Collection of hacks for Cairo components (bookmarks, raster plots)
  Add table of contents to PDFs and methods to plot raster plots in the
  middle of PDF plots.