diff --git a/js/app.js b/js/app.js
index d481b54..9a8cf24 100644
--- a/js/app.js
+++ b/js/app.js
@@ -1,10 +1,8 @@
 //init globals
-//var seekBar;
 var textArea;
 var Video;
 var filePath = false;
 var videoListener;
-var seekBar;
 var globalUser;
 var videoPath = undefined;
 var videoHash = undefined;
@@ -158,7 +156,7 @@ Ox.load({
                 ]) != -1) {
                   loadVideo(data.files[0]);
                 } else {
-                    alert('can only open video formats supported by browser');
+                    alert('You can only open videos in formats supported by the browser.');
                 }
             } else if(data.id == 'about') {
                 var html = Ox.tmpl("dialog_about", {});
@@ -243,9 +241,9 @@ Ox.load({
 
   //autosave every 1 minute.
   window.autosaveInterval = setInterval(function() {
-    if (typeof(videoHash) !== 'undefined') {
-      saveTxt();
-    }
+      if (!Ox.isUndefined(videoHash)) {
+          saveTxt();
+      }
   }, 60000);
 
 });
@@ -318,34 +316,6 @@ function loadVideo(videoFile) {
   });
 };
 
-
-/*
-Functions to generate preview while encoding: see http://firefogg.org/examples
-*/
-  //intialize interval to update preview and add event liseners.
-  //any previous listeners and intervals are cleared
-  var previewI=null;
-
-  function seekToEnd() {
-//    console.log("seeking to end of video");
-    var v = document.getElementById('previewVideo');
-    v.currentTime = v.duration-0.4;
-  }
-  //callback function render frame into canvas after seeking
-  function getFrame() {
-    var v = document.getElementById('previewVideo');
-    var canvas = document.getElementById('previewCanvas');
-    canvas.width = 400;
-    canvas.height = canvas.width * v.videoHeight/v.videoWidth;
-    var ctx = canvas.getContext("2d");
-    ctx.drawImage(v, 0, 0, canvas.width, canvas.height);
-  }
-
-/*
-End Preview functions
-*/
-
-
 $(window).unload(function() {
   saveTxt();
 });