add thumbnails

docs/index.html

@@ -32,6 +32,12 @@
             subtitle: {
                 url: './subtitle/dw_trailer_low.vtt'
             },
+            thumbnails: {
+                url: './img/thumbnails.jpg',
+                number: 100,
+                width: 160,
+                height: 90
+            },
             highlight: [
                 {
                     time: 20,