Updates Image.

def update(self):
        '''
        Updates Image.
        '''
        if self.hasproxy():
            img = Image()
            imageData = self.proxy.getImageData(self.imgFormat)
            img.height = imageData.description.height
            img.width = imageData.description.width
            img.format = imageData.description.format

            img.data = np.frombuffer(imageData.pixelData, dtype=np.uint8)
            img.data.shape = img.height, img.width, 3

            img.timeStamp = imageData.timeStamp.seconds + imageData.timeStamp.useconds * 1e-9


            self.lock.acquire()
            self.image = img
            self.lock.release()