diff --git a/dither-image.js b/dither-image.js
index bc963dd..8db870a 100644
--- a/dither-image.js
+++ b/dither-image.js
@@ -240,6 +240,7 @@ function colorize(input) {
 
         let output = zeroes(width);
         let distance = 0;
+        let shortest = Infinity;
 
         let nextError = new RGB(0, 0, 0);
 
@@ -249,7 +250,7 @@ function colorize(input) {
 
             // find the closest possible color
             // @todo consider doing the difference scoring in luminance and hue spaces
-            let shortest = Infinity;
+            shortest = Infinity;
             let pick = 1;
 
             for (let i = 0; i < palette.length; i++) {
@@ -276,6 +277,7 @@ function colorize(input) {
             output,
             palette,
             distance,
+            shortest,
             error: error.next
         };
     };