VideoPlaybackBehaviour.OnRenderObject ()

I've integrated vuforia cloud reco and video playback and it's working fine. But in the cloud reco script i'm referencing startplay video method like below,

videoScript = newImageTarget_videoType.GetComponentInChildren<VideoPlaybackBehaviour> ();

videoScript.m_path = videoString;

videoScript.Startplay();

In VideoPlaybackBehaviour:

public void Startplay()

{

// Find the icon plane (child of this object)

mIconPlane = transform.Find("Icon").gameObject;

// A filename or url must be set in the inspector

if (m_path == null || m_path.Length == 0)

{

Debug.Log("Please set a video url in the Inspector");

HandleStateChange(VideoPlayerHelper.MediaState.ERROR);

mCurrentState = VideoPlayerHelper.MediaState.ERROR;

this.enabled = false;

}

else

{

// Set the current state to Not Ready

HandleStateChange(VideoPlayerHelper.MediaState.NOT_READY);

mCurrentState = VideoPlayerHelper.MediaState.NOT_READY;

}

// Create the video player and set the filename

mVideoPlayer = new VideoPlayerHelper();

mVideoPlayer.SetFilename(m_path);

// Flip the plane as the video texture is mirrored on the horizontal

transform.localScale = new Vector3(-1 * Mathf.Abs(transform.localScale.x),

transform.localScale.y, transform.localScale.z);

// Scale the icon

ScaleIcon();

}

And i removed the void start function. So, now i'm getting error in the line if (mVideoPlayer.Init() == false) on void OnRenderObject() and below NullPointer;

NullReferenceException: Object reference not set to an instance of an object

VideoPlaybackBehaviour.OnRenderObject () (at Assets/Vuforia Video Playback/Scripts/VideoPlaybackBehaviour.cs:206)

But if i use the void Start menthod then the video is playing and busy texture only loading.

void Start()

{