java.lang.RuntimeException: startPreview failed
	at android.hardware.Camera.startPreview(Native Method)
	at com.google.android.gms.vision.a$f.onPictureTaken(Unknown Source:28)
	at android.hardware.Camera$EventHandler.handleMessage(Camera.java:1246)
	at android.os.Handler.dispatchMessage(Handler.java:106)
	at android.os.Looper.loopOnce(Looper.java:210)
	at android.os.Looper.loop(Looper.java:299)
	at android.app.ActivityThread.main(ActivityThread.java:8252)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:559)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:954)