diff --git a/src/js/controller/settings/exportimage/PngExportController.js b/src/js/controller/settings/exportimage/PngExportController.js
index a3d97e0c..8c9158cd 100644
--- a/src/js/controller/settings/exportimage/PngExportController.js
+++ b/src/js/controller/settings/exportimage/PngExportController.js
@@ -32,34 +32,10 @@
   ns.PngExportController.prototype.onZipButtonClick_ = function () {
     var zip = new window.JSZip();
 
-    function splittedExport() {
-      var layers = this.piskelController.getLayers();
-      for (var j = 0; this.piskelController.hasLayerAt(j); j++) {
-        var layer = this.piskelController.getLayerAt(j);
-        for (var i = 0; i < this.piskelController.getFrameCount(); i++) {
-          var frame = layer.getFrameAt(i);
-          var canvas = this.getFrameAsCanvas_(frame);
-          var basename = this.pngFilePrefixInput.value;
-          var filename = 'l' + j + '_' + basename + (i + 1) + '.png';
-          zip.file(filename, pskl.utils.CanvasUtils.getBase64FromCanvas(canvas) + '\n', {base64: true});
-        }
-      }
-    }
-
-    function mergedExport() {
-      for (var i = 0; i < this.piskelController.getFrameCount(); i++) {
-        var frame = this.piskelController.getFrameAt(i);
-        var canvas = this.getFrameAsCanvas_(frame);
-        var basename = this.pngFilePrefixInput.value;
-        var filename = basename + (i + 1) + '.png';
-        zip.file(filename, pskl.utils.CanvasUtils.getBase64FromCanvas(canvas) + '\n', {base64: true});
-      }
-    }
-
     if (this.splitByLayersCheckbox.checked) {
-      splittedExport.call(this);
+      this.splittedExport_(zip);
     } else {
-      mergedExport.call(this);
+      this.mergedExport_(zip);
     }
 
     var fileName = this.getPiskelName_() + '.zip';
@@ -71,6 +47,30 @@
     pskl.utils.FileUtils.downloadAsFile(blob, fileName);
   };
 
+  ns.PngExportController.prototype.mergedExport_ = function (zip) {
+    for (var i = 0; i < this.piskelController.getFrameCount(); i++) {
+      var frame = this.piskelController.getFrameAt(i);
+      var canvas = this.getFrameAsCanvas_(frame);
+      var basename = this.pngFilePrefixInput.value;
+      var filename = basename + (i + 1) + '.png';
+      zip.file(filename, pskl.utils.CanvasUtils.getBase64FromCanvas(canvas) + '\n', {base64: true});
+    }
+  };
+
+  ns.PngExportController.prototype.splittedExport_ = function (zip) {
+    var layers = this.piskelController.getLayers();
+    for (var j = 0; this.piskelController.hasLayerAt(j); j++) {
+      var layer = this.piskelController.getLayerAt(j);
+      for (var i = 0; i < this.piskelController.getFrameCount(); i++) {
+        var frame = layer.getFrameAt(i);
+        var canvas = this.getFrameAsCanvas_(frame);
+        var basename = this.pngFilePrefixInput.value;
+        var filename = 'l' + j + '_' + basename + (i + 1) + '.png';
+        zip.file(filename, pskl.utils.CanvasUtils.getBase64FromCanvas(canvas) + '\n', {base64: true});
+      }
+    }
+  };
+
   ns.PngExportController.prototype.getFrameAsCanvas_ = function (frame) {
     var canvasRenderer = new pskl.rendering.CanvasRenderer(frame, 1);
     canvasRenderer.drawTransparentAs(Constants.TRANSPARENT_COLOR);