diff --git a/app/src/main/java/com/frank/ffmpeg/activity/VideoHandleActivity.kt b/app/src/main/java/com/frank/ffmpeg/activity/VideoHandleActivity.kt
index 5df9aa1..fdf0006 100644
--- a/app/src/main/java/com/frank/ffmpeg/activity/VideoHandleActivity.kt
+++ b/app/src/main/java/com/frank/ffmpeg/activity/VideoHandleActivity.kt
@@ -118,7 +118,8 @@ class VideoHandleActivity : BaseActivity() {
                 R.id.btn_speed,
                 R.id.btn_flv,
                 R.id.btn_thumbnail,
-                R.id.btn_add_subtitle
+                R.id.btn_add_subtitle,
+                R.id.btn_rotate
         )
     }
 
@@ -328,11 +329,16 @@ class VideoHandleActivity : BaseActivity() {
             }
             R.id.btn_add_subtitle//add subtitle into video
             -> {
-                Log.e(TAG, "add subtitle...")
                 val subtitlePath = PATH + File.separator + "test.ass"
                 val addSubtitlePath = PATH + File.separator + "subtitle" + suffix
                 commandLine = FFmpegUtil.addSubtitleIntoVideo(srcFile, subtitlePath, addSubtitlePath)
             }
+            R.id.btn_rotate// set the rotate degree of video
+            -> {
+                val rotateDegree = 90
+                val addSubtitlePath = PATH + File.separator + "rotate" + rotateDegree + suffix
+                commandLine = FFmpegUtil.rotateVideo(srcFile, rotateDegree, addSubtitlePath)
+            }
             else -> {
             }
         }
diff --git a/app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java b/app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java
index cdb9342..0b54844 100644
--- a/app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java
+++ b/app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java
@@ -693,4 +693,10 @@ public class FFmpegUtil {
         return pushStreams.split(" ");
     }
 
+    public static String[] rotateVideo(String inputPath, int rotateDegree, String outputPath) {
+        String rotateCmd = "ffmpeg -i %s -c copy -metadata:s:v:0 rotate=%d %s";
+        rotateCmd = String.format(Locale.getDefault(), rotateCmd, inputPath, rotateDegree, outputPath);
+        return rotateCmd.split(" ");
+    }
+
 }
diff --git a/app/src/main/res/layout/activity_video_handle.xml b/app/src/main/res/layout/activity_video_handle.xml
index f2959d0..f1ecc29 100644
--- a/app/src/main/res/layout/activity_video_handle.xml
+++ b/app/src/main/res/layout/activity_video_handle.xml
@@ -149,6 +149,13 @@
                 android:layout_marginTop="4dp"
                 android:text="@string/video_thumbnail"/>
 
+            <Button
+                android:id="@+id/btn_rotate"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="4dp"
+                android:text="@string/video_rotate"/>
+
         </LinearLayout>
     </ScrollView>