diff --git a/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java b/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java
index bb5ba33..16587da 100644
--- a/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java
+++ b/app/src/main/java/com/jiangdg/usbcamera/view/USBCameraActivity.java
@@ -139,6 +139,7 @@ public class USBCameraActivity extends AppCompatActivity implements CameraDialog
         mUVCCameraView = (CameraViewInterface) mTextureView;
         mUVCCameraView.setCallback(this);
         mCameraHelper = UVCCameraHelper.getInstance();
+        mCameraHelper.setDefaultFrameFormat(UVCCameraHelper.FRAME_FORMAT_YUYV);
         mCameraHelper.initUSBMonitor(this, mUVCCameraView, listener);
 
 
@@ -242,7 +243,7 @@ public class USBCameraActivity extends AppCompatActivity implements CameraDialog
                 }
                 if (!mCameraHelper.isRecording()) {
                     String videoPath = UVCCameraHelper.ROOT_PATH + System.currentTimeMillis();
-//                    FileUtils.createfile(FileUtils.ROOT_PATH + "test666.h264");
+                    FileUtils.createfile(FileUtils.ROOT_PATH + "test666.h264");
                     RecordParams params = new RecordParams();
                     params.setRecordPath(videoPath);
                     params.setRecordDuration(0);                        // 设置为0，不分割保存
@@ -252,7 +253,7 @@ public class USBCameraActivity extends AppCompatActivity implements CameraDialog
                         public void onEncodeResult(byte[] data, int offset, int length, long timestamp, int type) {
                             // type = 1,h264 video stream
                             if (type == 1) {
-//                                FileUtils.putFileStream(data, offset, length);
+                                FileUtils.putFileStream(data, offset, length);
                             }
                             // type = 0,aac audio stream
                             if(type == 0) {
@@ -268,7 +269,7 @@ public class USBCameraActivity extends AppCompatActivity implements CameraDialog
                     showShortMsg("start record...");
                     mSwitchVoice.setEnabled(false);
                 } else {
-//                    FileUtils.releaseFile();
+                    FileUtils.releaseFile();
                     mCameraHelper.stopRecording();
                     showShortMsg("stop record...");
                     mSwitchVoice.setEnabled(true);
diff --git a/libusbcamera/src/main/java/com/jiangdg/usbcamera/UVCCameraHelper.java b/libusbcamera/src/main/java/com/jiangdg/usbcamera/UVCCameraHelper.java
index 194ff46..d03d6ab 100644
--- a/libusbcamera/src/main/java/com/jiangdg/usbcamera/UVCCameraHelper.java
+++ b/libusbcamera/src/main/java/com/jiangdg/usbcamera/UVCCameraHelper.java
@@ -33,11 +33,12 @@ public class UVCCameraHelper {
     private int previewWidth = 640;
     private int previewHeight = 480;
     // 高分辨率YUV格式帧率较低
-    private static int FRAME_FORMAT_YUYV = UVCCamera.FRAME_FORMAT_YUYV;
+    public static final int FRAME_FORMAT_YUYV = UVCCamera.FRAME_FORMAT_YUYV;
     // 默认使用MJPEG
-    private static int FRAME_FORMAT_MJPEG = UVCCamera.FRAME_FORMAT_MJPEG;
-    public static int MODE_BRIGHTNESS = UVCCamera.PU_BRIGHTNESS;
-    public static int MODE_CONTRAST = UVCCamera.PU_CONTRAST;
+    public static final int FRAME_FORMAT_MJPEG = UVCCamera.FRAME_FORMAT_MJPEG;
+    public static final int MODE_BRIGHTNESS = UVCCamera.PU_BRIGHTNESS;
+    public static final int MODE_CONTRAST = UVCCamera.PU_CONTRAST;
+    private int mFrameFormat = FRAME_FORMAT_MJPEG;
 
     private static UVCCameraHelper mCameraHelper;
     // USB Manager
@@ -151,7 +152,7 @@ public class UVCCameraHelper {
         // initialize camera handler
         mCamView.setAspectRatio(previewWidth / (float)previewHeight);
         mCameraHandler = UVCCameraHandler.createHandler(mActivity, mCamView, 2,
-                previewWidth, previewHeight, FRAME_FORMAT_MJPEG);
+                previewWidth, previewHeight, mFrameFormat);
     }
 
     public void updateResolution(int width, int height) {
@@ -166,7 +167,7 @@ public class UVCCameraHelper {
         }
         mCamView.setAspectRatio(previewWidth / (float)previewHeight);
         mCameraHandler = UVCCameraHandler.createHandler(mActivity,mCamView, 2,
-                previewWidth, previewHeight, FRAME_FORMAT_MJPEG);
+                previewWidth, previewHeight, mFrameFormat);
         openCamera(mCtrlBlock);
         new Thread(new Runnable() {
             @Override
@@ -332,6 +333,13 @@ public class UVCCameraHelper {
         this.previewHeight = defaultHeight;
     }
 
+    public void setDefaultFrameFormat(int format) {
+        if(mUSBMonitor != null) {
+            throw new IllegalStateException("setDefaultFrameFormat should be call before initMonitor");
+        }
+        this.mFrameFormat = format;
+    }
+
     public int getPreviewWidth() {
         return previewWidth;
     }
diff --git a/libusbcamera/src/main/java/com/serenegiant/usb/common/AbstractUVCCameraHandler.java b/libusbcamera/src/main/java/com/serenegiant/usb/common/AbstractUVCCameraHandler.java
index b05a9ac..fd7f7f9 100644
--- a/libusbcamera/src/main/java/com/serenegiant/usb/common/AbstractUVCCameraHandler.java
+++ b/libusbcamera/src/main/java/com/serenegiant/usb/common/AbstractUVCCameraHandler.java
@@ -531,6 +531,7 @@ public  abstract class AbstractUVCCameraHandler extends Handler {
 			try {
 				mUVCCamera.setPreviewSize(mWidth, mHeight, 1, 31, mPreviewMode, mBandwidthFactor);
 				// 获取USB Camera预览数据，使用NV21颜色会失真
+				// 无论使用YUV还是MPEG，setFrameCallback的设置效果一致
 //				mUVCCamera.setFrameCallback(mIFrameCallback, UVCCamera.PIXEL_FORMAT_NV21);
 				mUVCCamera.setFrameCallback(mIFrameCallback, UVCCamera.PIXEL_FORMAT_YUV420SP);
 			} catch (final IllegalArgumentException e) {