diff --git a/README.md b/README.md
index 6b14394..d878ece 100644
--- a/README.md
+++ b/README.md
@@ -36,29 +36,40 @@ html code:
 index.js code:
 
     var imgs=document.getElementsByName('imgView');
-    var args={ 'showThumbnail':true,
-               'selectMode':101,//101=PICKER_IMAGE_VIDEO , 100=PICKER_IMAGE , 102=PICKER_VIDEO
-               'maxSelectCount':12, //default 40 (Optional)
-               'maxSelectSize':188743680,//188743680=180M (Optional)
-              };
+    var args={
+        'selectMode':101,//101=PICKER_IMAGE_VIDEO , 100=PICKER_IMAGE , 102=PICKER_VIDEO
+        'maxSelectCount':40, //default 40 (Optional)
+        'maxSelectSize':188743680,//188743680=180M (Optional)
+    };
 
     document.getElementById('openBtn').onclick=function(){
+          MediaPicker.getMedias(args,function(dataArray){
+              //dataArray [{mediaType: "image", path:'/storage/emulated/0/DCIM/Camera/20170808_145202.jpg', path:'/storage/emulated/0/DCIM/Camera/20170808_145202.jpg'}]
+              getThumbnail(dataArray);
+          },err())
+    };
 
-        MediaPicker.getMedias(args,function(dataArray){
-            //dataArray [{mediaType: "image",rotate: 90, path:'/storage/emulated/0/DCIM/Camera/20170808_145202.jpg' thumbnailBase64: '9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAEBAQEBAQEBAQEB'}]
-            for(var i=0; i<dataArray.length; i++){
-                imgs[i].src= 'data:image/jpeg;base64,'+dataArray[i].thumbnailBase64;
-                imgs[i].setAttribute('style', 'transform:rotate(' + dataArray[i].rotate + 'deg)');
-            }
-        },function(err){
-            console.log(err);
-        })
-     };
+    function getThumbnail(dataArray){
+          for(var i=0; i<dataArray.length; i++){
+                //dataArray[i].thumbnailQuality=50; (Optional)
+                //loading(); //show loading ui
+                MediaPicker.extractThumbnail(dataArray[i],function(data){
+                            imgs[data.index].src= 'data:image/jpeg;base64,'+data.thumbnailBase64;
+                            imgs[data.index].setAttribute('style', 'transform:rotate(' + data.exifRotate + 'deg)');
+                },err());
+          }
+    }
 
-     document.getElementById('uploadBtn').onclick=function() {
+    document.getElementById('uploadBtn').onclick=function() {
         //please:  cordova plugin add cordova-plugin-file-transfer
         //see:  https://cordova.apache.org/docs/en/latest/reference/cordova-plugin-file-transfer/index.html
-     };
+    };
+
+    function err(data){
+        console.log(err);
+    }
+
+    function loading(){}