diff --git a/coverage/coverage.js b/coverage/coverage.js
new file mode 100644
index 0000000..c15ac79
--- /dev/null
+++ b/coverage/coverage.js
@@ -0,0 +1,24 @@
+
+function gyayscale(context) {
+    var canvas = context.canvas;
+    var width = canvas.width;
+    var height = canvas.height;
+    var imageData = context.getImageData(0, 0, width, height);
+    var data = imageData.data;
+    
+    for (i = 0; i < data.length; i += 4) {
+        var r = data[i];
+        var g = data[i + 1];
+        var b = data[i + 2];
+        var v = 0.2126 * r + 0.7152 * g + 0.0722 * b;
+        if (v === 0.0) {
+            v = 255.0;
+        }
+        data[i + 0] = v;
+        data[i + 1] = v;
+        data[i + 2] = v;
+        data[i + 3] = 255;
+    }
+    context.putImageData(imageData, 0, 0);
+}
+
diff --git a/coverage/fuel3.html b/coverage/fuel3.html
index 68fd56f..9e6009f 100644
--- a/coverage/fuel3.html
+++ b/coverage/fuel3.html
@@ -72,6 +72,7 @@
 <script src="../lib/ol-4.5.0/ol.js"></script>
 <script src="../lib/Leaflet.MapboxVectorTile.js"></script>
 <script src="https://code.jquery.com/jquery-2.1.1.min.js"></script>
+<script src="coverage.js"></script>
 <script>
     var jsonurl = '/gitbucket/yuu/osmCoverageBin/raw/master/GML_FUEL/coverage.fuel.json';
     $.getJSON(jsonurl, function(data) {
@@ -99,13 +100,16 @@
         title: "OpenStreetMap",
         visible: true
     });
+    grayOsmLayer.on('postcompose', function(event) {
+        grayscale(event.context);
+    });
 
     const fuel0 = new ol.layer.VectorTile({
         source: new ol.source.VectorTile({
             format: new ol.format.MVT(),
             url: "./tiles/tileFuel0/" + "{z}/{x}/{y}.pbf"
         }),
-        title: "Fuel: 未入力",
+        title: "Fuel 0: 未入力",
         visible: true,
         opacity: 1,
         style: function(feature){
@@ -125,7 +129,7 @@
             format: new ol.format.MVT(),
             url: "./tiles/tileFuel1/" + "{z}/{x}/{y}.pbf"
         }),
-        title: "Fuel: 未入力",
+        title: "Fuel 1: 入力済",
         visible: true,
         opacity: 1,
         style: function(feature){
@@ -145,7 +149,7 @@
             format: new ol.format.MVT(),
             url: "./tiles/tileFuel2/" + "{z}/{x}/{y}.pbf"
         }),
-        title: "Fuel: 未入力",
+        title: "Fuel 2: 完了",
         visible: true,
         opacity: 1,
         style: function(feature){