diff --git a/Live/src/main/java/com/frank/live/stream/CameraHelper.java b/Live/src/main/java/com/frank/live/stream/CameraHelper.java
index 6de4a7d..3fa656d 100644
--- a/Live/src/main/java/com/frank/live/stream/CameraHelper.java
+++ b/Live/src/main/java/com/frank/live/stream/CameraHelper.java
@@ -41,11 +41,8 @@ public class CameraHelper implements SurfaceHolder.Callback, Camera.PreviewCallb
 
     private void stopPreview() {
         if (mCamera != null) {
-            //预览数据回调接口
             mCamera.setPreviewCallback(null);
-            //停止预览
             mCamera.stopPreview();
-            //释放摄像头
             mCamera.release();
             mCamera = null;
         }
@@ -102,7 +99,7 @@ public class CameraHelper implements SurfaceHolder.Callback, Camera.PreviewCallb
     private void setPreviewSize(Camera.Parameters parameters) {
         List<Camera.Size> supportedPreviewSizes = parameters.getSupportedPreviewSizes();
         Camera.Size size = supportedPreviewSizes.get(0);
-        //选择最合适的camera支持分辨率
+        //select the best resolution of camera
         int m = Math.abs(size.height * size.width - mWidth * mHeight);
         supportedPreviewSizes.remove(0);
         for (Camera.Size next : supportedPreviewSizes) {
@@ -151,8 +148,8 @@ public class CameraHelper implements SurfaceHolder.Callback, Camera.PreviewCallb
                 rotation90(data);
                 break;
             case Surface.ROTATION_90:
-                break;
             case Surface.ROTATION_270:
+            default:
                 break;
         }
         mPreviewCallback.onPreviewFrame(bytes, camera);
@@ -163,7 +160,7 @@ public class CameraHelper implements SurfaceHolder.Callback, Camera.PreviewCallb
         int index = 0;
         int ySize = mWidth * mHeight;
         int uvHeight = mHeight / 2;
-        //后置摄像头顺时针旋转90度
+        //back camera rotate 90 deree
         if (mCameraId == Camera.CameraInfo.CAMERA_FACING_BACK) {
 
             for (int i = 0; i < mWidth; i++) {
@@ -181,7 +178,7 @@ public class CameraHelper implements SurfaceHolder.Callback, Camera.PreviewCallb
                 }
             }
         } else {
-            //逆时针旋转90度
+            //rotate 90 degree
             for (int i = 0; i < mWidth; i++) {
                 int nPos = mWidth - 1;
                 for (int j = 0; j < mHeight; j++) {
diff --git a/Live/src/main/java/com/frank/live/stream/VideoStreamNew.java b/Live/src/main/java/com/frank/live/stream/VideoStreamNew.java
index b4a52ff..0dc0c00 100644
--- a/Live/src/main/java/com/frank/live/stream/VideoStreamNew.java
+++ b/Live/src/main/java/com/frank/live/stream/VideoStreamNew.java
@@ -15,7 +15,7 @@ import com.frank.live.camera2.Camera2Listener;
 import com.frank.live.param.VideoParam;
 
 /**
- * 视频推流:使用Camera2
+ * Pushing video stream: using Camera2
  * Created by frank on 2020/02/12.
  */
 public class VideoStreamNew implements TextureView.SurfaceTextureListener, Camera2Listener {
@@ -42,7 +42,7 @@ public class VideoStreamNew implements TextureView.SurfaceTextureListener, Camer
     }
 
     /**
-     * 开始预览
+     * start previewing
      */
     private void startPreview() {
         int rotateDegree = 0;
@@ -85,7 +85,7 @@ public class VideoStreamNew implements TextureView.SurfaceTextureListener, Camer
     }
 
     /**
-     * 停止预览
+     * stop previewing
      */
     private void stopPreview() {
         if (camera2Helper != null) {
@@ -117,7 +117,8 @@ public class VideoStreamNew implements TextureView.SurfaceTextureListener, Camer
     }
 
     /**
-     * nv21摄像头数据
+     * camere preview frame data
+     *
      * @param y plane of y
      * @param u plane of u
      * @param v plane of v
diff --git a/Live/src/main/java/com/frank/live/view/SmartCameraView.java b/Live/src/main/java/com/frank/live/view/SmartCameraView.java
index 01eead3..e36a06a 100644
--- a/Live/src/main/java/com/frank/live/view/SmartCameraView.java
+++ b/Live/src/main/java/com/frank/live/view/SmartCameraView.java
@@ -156,9 +156,9 @@ public class SmartCameraView extends GLSurfaceView implements GLSurfaceView.Rend
         mGLPreviewBuffer = ByteBuffer.allocate(mPreviewWidth * mPreviewHeight * 4);
 
         mInputAspectRatio = mPreviewWidth > mPreviewHeight ?
-            (float) mPreviewWidth / mPreviewHeight : (float) mPreviewHeight / mPreviewWidth;
+                (float) mPreviewWidth / mPreviewHeight : (float) mPreviewHeight / mPreviewWidth;
 
-        return new int[] { mPreviewWidth, mPreviewHeight };
+        return new int[]{mPreviewWidth, mPreviewHeight};
     }
 
     public boolean setFilter(final MagicFilterType type) {
@@ -189,7 +189,7 @@ public class SmartCameraView extends GLSurfaceView implements GLSurfaceView.Rend
             queueEvent(new Runnable() {
                 @Override
                 public void run() {
-                    GLES20.glDeleteTextures(1, new int[]{ mOESTextureId }, 0);
+                    GLES20.glDeleteTextures(1, new int[]{mOESTextureId}, 0);
                     mOESTextureId = OpenGLUtils.NO_TEXTURE;
                 }
             });
@@ -311,11 +311,11 @@ public class SmartCameraView extends GLSurfaceView implements GLSurfaceView.Rend
         Camera.Size psize;
         for (int i = 0; i < pictureSizes.size(); i++) {
             psize = pictureSizes.get(i);
-            Log.i(TAG,psize.width+" x "+psize.height);
+            Log.i(TAG, psize.width + " x " + psize.height);
         }
         for (int i = 0; i < previewSizes.size(); i++) {
             psize = previewSizes.get(i);
-            Log.i(TAG,psize.width+" x "+psize.height);
+            Log.i(TAG, psize.width + " x " + psize.height);
         }
     }