diff --git a/app/src/main/java/com/frank/ffmpeg/util/TimeUtil.java b/app/src/main/java/com/frank/ffmpeg/util/TimeUtil.java
index b0f9243..ede7d47 100644
--- a/app/src/main/java/com/frank/ffmpeg/util/TimeUtil.java
+++ b/app/src/main/java/com/frank/ffmpeg/util/TimeUtil.java
@@ -6,18 +6,19 @@ import java.util.Date;
 import java.util.Locale;
 
 /**
- * 时间转换工具类
+ * the tool of time transforming
  * Created by frank on 2018/11/12.
  */
 
 public class TimeUtil {
 
-    private static final String YMDHMS= "yyyy-MM-dd HH:mm:ss";
+    private static final String YMDHMS = "yyyy-MM-dd HH:mm:ss";
 
     /**
-     * 时间戳年月日时分秒
+     * convert timestramp into String
+     *
      * @param time time
-     * @return 年月日时分秒 yyyy/MM/dd HH:mm:ss
+     * @return yyyy/MM/dd HH:mm:ss
      */
     public static String getDetailTime(long time) {
         SimpleDateFormat format = new SimpleDateFormat(YMDHMS, Locale.getDefault());
@@ -26,9 +27,10 @@ public class TimeUtil {
     }
 
     /**
-     * 时间转为时间戳
+     * convert normal time into timestamp
+     *
      * @param time time
-     * @return 时间戳
+     * @return timestamp
      */
     public static long getLongTime(String time, Locale locale) {
         SimpleDateFormat simpleDateFormat = new SimpleDateFormat(YMDHMS, locale);
@@ -41,37 +43,38 @@ public class TimeUtil {
         return 0;
     }
 
-    private static String addZero(int time){
-        if (time >= 0 && time < 10){
-            return  "0" + time;
-        }else if(time >= 10){
+    private static String addZero(int time) {
+        if (time >= 0 && time < 10) {
+            return "0" + time;
+        } else if (time >= 10) {
             return "" + time;
-        }else {
+        } else {
             return "";
         }
     }
 
     /**
-     * 获取视频时长
+     * convert timestamp into video time
+     *
      * @param time time
-     * @return 视频时长
+     * @return video time
      */
-    public static String getVideoTime(long time){
+    public static String getVideoTime(long time) {
         if (time <= 0)
             return null;
         time = time / 1000;
-        int second, minute=0, hour=0;
-        second = (int)time % 60;
+        int second, minute = 0, hour = 0;
+        second = (int) time % 60;
         time = time / 60;
-        if (time > 0){
-            minute = (int)time % 60;
-            hour = (int)time / 60;
+        if (time > 0) {
+            minute = (int) time % 60;
+            hour = (int) time / 60;
         }
-        if (hour > 0){
+        if (hour > 0) {
             return addZero(hour) + ":" + addZero(minute) + ":" + addZero(second);
-        }else if (minute > 0){
+        } else if (minute > 0) {
             return addZero(minute) + ":" + addZero(second);
-        }else {
+        } else {
             return "00:" + addZero(second);
         }
     }
diff --git a/app/src/main/java/com/frank/ffmpeg/view/VideoPreviewBar.java b/app/src/main/java/com/frank/ffmpeg/view/VideoPreviewBar.java
index 3d4f69a..d9a192c 100644
--- a/app/src/main/java/com/frank/ffmpeg/view/VideoPreviewBar.java
+++ b/app/src/main/java/com/frank/ffmpeg/view/VideoPreviewBar.java
@@ -19,7 +19,7 @@ import com.frank.ffmpeg.util.ScreenUtil;
 import com.frank.ffmpeg.util.TimeUtil;
 
 /**
- * 视频拖动实时预览的控件
+ * the custom view of preview SeekBar
  * Created by frank on 2019/11/16.
  */