Television Control by Hand Gestures

This paper presents a simple vision based approach to use hands as natural mode of television control. The setup requires a camera on the television set which keeps track of the hand gestures made my the user sitting at a particular place and when gesture is observe, the system is triggered and the icon appears on the television which shows that the hands have been detected. After that, icon appears which can be moved by the motion of the hand. To select the control, the icon needs to be kept stagnant/ hovering about the control button. The gesture recognition system also works when the television is switched off and detection of gesture triggers on the control mode.

For the detection of the hands in the image, they have used a normalized correlation measure between the hand template and the image frame. The location of the hand in the image frame would be the region of maximum correlation. For measuring the correlation, orientation information or the pixel information can be used. However, they have found that the orientation information has proved to be a little bit better.For measuring speed, they have used the derivative information. Stationary background is removed by simply taking a running average of the image frames of the scene ans subtracting the frames. This causes removal of stationary objects in the image frame.For ending the control mode, the user just have to close his hand.

In order to save computational cost in searching for the template in the complete image frame,system finds the position of the best match of the current filter and searches in the local region with the other template to find the position and value of the filter giving the best correlation match.


In order to accidentally press a trigger, they have used a threshold based on the time of non activity. Their system is limited by the limited field of view which is 250 for searching trigger and 15 degree for tracking .


Discussion.

This is a simple vision based approach to track the hand and use its motion for controlling the volume of the television set. Since they are using orientation, I believe if some one keeps hand in the direction which is in slanting direction to the principle axis direction of the camera, it will be difficult to use the template match as for template matching the template should match the shape of the object. Also, I believe , considering the complex nature of the current television controls,it would be difficult to use such a remote control as it might be very tiring. Also, i am unable to understand if the distance from the television also affects the recognition as the size of the hands would change.