[Change]

修改速度取值，更新行车记录仪代码。
DEMO必须依附于预览获取YUV数据，不符合需求，这里先接入直播，后续需要按照源码抽离直接通过USB获取YUV的服务

Signed-off-by: donghongyu <donghongyu@zhidaoauto.com>

libraries/map-usbcamera/src/main/java/com/mogo/usbcamera/USBCameraHelper.java

@@ -0,0 +1,39 @@
+package com.mogo.usbcamera;
+
+import com.serenegiant.usb.USBMonitor;
+
+/**
+ * @author donghongyu
+ * USB摄像头方案，获取权限、获取YUV数据
+ */
+public class USBCameraHelper {
+    private static USBCameraHelper mCameraHelper;
+    /**
+     * USB Manager
+     */
+    private USBMonitor mUSBMonitor;
+
+    private USBCameraHelper() {
+    }
+
+    public static USBCameraHelper getInstance() {
+        if (mCameraHelper == null) {
+            mCameraHelper = new USBCameraHelper();
+        }
+        return mCameraHelper;
+    }
+
+
+
+    public void registerUSB() {
+        if (mUSBMonitor != null) {
+            mUSBMonitor.register();
+        }
+    }
+
+    public void unregisterUSB() {
+        if (mUSBMonitor != null) {
+            mUSBMonitor.unregister();
+        }
+    }
+}