68. The method of claim 67 , further comprising: recording the changes of position of the object; quantizing the changes of the position of the object; and recognizing the visual gesture based on quantized changes of position of the object.
68. The method of claim 67 , further comprising: recording the changes of position of the object; quantizing the changes of the position of the object; and recognizing the visual gesture based on quantized changes of position of the object. 70. The method of claim 68 , wherein recording the changes of position of the object comprises: recording a change of position of object by reference position change of the object, wherein the reference position change of the object indicates the change over a pre-defined reference position of the object.