请问下程序运行在Bitmap.createBitmap位置显示getWidth空指针异常，该怎么弄呀？？照着老师的代码敲的，检查脸三遍确定没有打错，望大神解答，谢谢！附上错误提示： 01-21 05:09:17.898    2566-2696/com.zhaogui.lookface E/AndroidRuntime﹕ FATAL EXCEPTION: Thread-176
    Process: com.zhaogui.lookface, PID: 2566
    java.lang.NullPointerException: Attempt to invoke virtual method 'int android.graphics.Bitmap.getWidth()' on a null object reference
            at com.zhaogui.lookface.FaceppDetect$1.run(FaceppDetect.java:37)
            at java.lang.Thread.run(Thread.java:818)