From 07efde77b6d14a576734cc4526d26c34383182e8 Mon Sep 17 00:00:00 2001
From: remolaubacher <remo.laubacher@gmail.com>
Date: Wed, 17 Jun 2015 08:30:38 +0200
Subject: [PATCH] don't create canvas from empty string

---
 signature_pad.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/signature_pad.js b/signature_pad.js
index dac9a26c..4dc31906 100644
--- a/signature_pad.js
+++ b/signature_pad.js
@@ -115,6 +115,9 @@ var SignaturePad = (function (document) {
     };
 
     SignaturePad.prototype.fromDataURL = function (dataUrl) {
+        if (!dataUrl) {
+            return;
+        }
         var self = this,
             image = new Image(),
             ratio = window.devicePixelRatio || 1,