Gesture recognition system and gesture recognition method based on sharpness values

Abstract

A gesture recognition system includes an image capturing device, a memory unit and a processing unit. The image capturing device includes a zoom lens and captures an image frame with a focus length. The memory unit previously saves a lookup table of depths versus sharpness associated with at least one the focus length of the zoom lens. The processing unit is configured to calculate a current sharpness value of at least one object image in the image frame and to obtain a current depth of the object image according to the lookup table.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This application claims the priority benefit of Taiwan Patent Application Serial Number 101132634, filed on Sep. 7, 2012, the full disclosure of which is incorporated herein by reference.BACKGROUND[0002]1. Field of the Disclosure[0003]This disclosure generally relates to a human machine interface device and, more particularly, to a gesture recognition system and method employing a zoom lens.[0004]2. Description of the Related Art[0005]In recent years, introducing the interactive mechanism into multimedia systems so as to improve the operational convenience has become a popular technique, wherein the gesture recognition is an important technique adapted to replace the traditional mouse, stick or remote controller.[0006]A gesture recognition system generally includes an image sensor and a processing unit, wherein the image sensor is configured to capture images containing an operating object, e.g. a finger; and the processing unit is configu...

AI Technical Summary

Benefits of technology

[0010]The present disclosure provides a gesture recognition system and method that may determine a current depth of at least one object according to a previously constructed lookup table regarding object depths versus sharpness.

[0011]The present disclosure further provides a gesture recognition system and method that may remove the object outside a predetermined operable range so as to eliminate the interference from environment objects.

[0012]The present disclosure further provides a gesture recognition system and method that may reduce the consumption power of the processing unit in operation by employing sub-sampling technique.

[0016]In one aspect, an operable range may be previously set and saved so that the processing unit may remove the object image outside the operable range accordingly thereby eliminating the interference from environment objects, wherein the operable range may be a sharpness range or a depth range set before shipment or in a setup stage before the system is actually operated.

[0017]In one aspect, the processing unit is further configured to perform a sub-sampling process on the image frame before obtaining the current sharpness value so as to reduce the consumption power of the processing unit in operation, wherein a sub-sampled pixel area of the sub-sampling process is at least a 4×4 pixel area.

Problems solved by technology

However, the processing unit 92 is not able to identify a depth of the object O according to the images, and when the focus range FR includes another object, e.g. a background object O′, the processing unit 92 can not distinguish the objects O and O′ such that the control error may occur.

However, when the pattern is interfered by ambient light sources, the control error may still occur.

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