diff --git a/src/define.sh b/src/define.sh
index 1f66aa8..23229e5 100644
--- a/src/define.sh
+++ b/src/define.sh
@@ -1,8 +1,8 @@
 #!/usr/bin/env bash
 set -Eeuo pipefail
 
-: "${XRES:=""}"
-: "${YRES:=""}"
+: "${WIDTH:=""}"
+: "${HEIGHT:=""}"
 : "${VERIFY:=""}"
 : "${REGION:=""}"
 : "${MANUAL:=""}"