Architecture for controlling a computer using hand gestures

Abstract

Architecture for implementing a perceptual user interface. The architecture comprises alternative modalities for controlling computer application programs and manipulating on-screen objects through hand gestures or a combination of hand gestures and verbal commands. The perceptual user interface system includes a tracking component that detects object characteristics of at least one of a plurality of objects within a scene, and tracks the respective object. Detection of object characteristics is based at least in part upon image comparison of a plurality of images relative to a course mapping of the images. A seeding component iteratively seeds the tracking component with object hypotheses based upon the presence of the object characteristics and the image comparison. A filtering component selectively removes the tracked object from the object hypotheses and / or at least one object hypothesis from the set of object hypotheses based upon predetermined removal criteria.

Description

RELATED APPLICATIONS[0001]This is a continuation of U.S. patent application Ser. No. 10 / 396,653, filed on Mar. 25, 2003 and entitled, “ARCHITECTURE FOR CONTROLLING A COMPUTER USING HAND GESTURES,” the entire contents of which is hereby incorporated by reference.TECHNICAL FIELD[0002]The present invention relates generally to controlling a computer system, and more particularly to a system and method to implement alternative modalities for controlling computer application programs and manipulating on-screen objects through hand gestures or a combination of hand gestures and verbal commands.BACKGROUND OF THE INVENTION[0003]A user interface facilitates the interaction between a computer and computer user by enhancing the user's ability to utilize application programs. The traditional interface between a human user and a typical personal computer is implemented with graphical displays and is generally referred to as a graphical user interface (GUI). Input to the computer or particular ap...

AI Technical Summary

Benefits of technology

[0018]The present invention relates to a system and methodology to implement a perceptual user interface comprising alternative modalities for controlling computer application programs and manipulating on-screen objects through hand gestures or a combination of hand gestures and verbal commands. A perceptual user interface system is provided that detects and tracks hand and / or object movements, and provides for the control of application programs and manipulation of on-screen objects in response to hand or object movements performed by the user. The system operates in real time, is robust, responsive, and introduces a reduced computational load due to “lightweight” sparse stereo image processing by not imaging every pixel, but only a reduced representation of image pixels. That is, the depth at every pixel in the image is not computed, which is the typical approach in conventional correlation-based stereo systems. The present invention utilizes the depth information at specific locations in the image that correspond to object hypotheses.

[0019]The system provides a relatively inexpensive capability for the recognition of hand gestures.

[0022]In accordance with another aspect thereof, the present invention facilitates adapting the system to the particular preferences of an individual user. The system and method allow the user to tailor the system to recognize specific hand gestures and verbal commands and to associate these hand gestures and verbal commands with particular actions to be taken. This capability allows different users, which may prefer to make different motions for a given command, the ability to tailor the system in a way most efficient for their personal use. Similarly, different users can choose to use different verbal commands to perform the same function. For example, one user may choose to say “Release” to stop moving a window while another may wish to say “Quit”.

[0025]In accordance with still another aspect of the invention, two video cameras are mounted substantially parallel to each other to generate video images that are used to determine the depth (distance from the camera, display, or other point of reference) of a moving object using a lightweight sparse stereo technique. The lightweight sparse stereo technique reduces the computational requirements of the system and the depth component is used as an element in determining whether that particular object is the nearest object within the engagement volume.

Problems solved by technology

There are, however, many applications where the traditional user interface is less practical or efficient.

The traditional computer interface is not ideal for a number of applications.

Manipulation of the presentation by the presenter is generally controlled through use of awkward remote controls, which frequently suffer from inconsistent and less precise operation, or require the cooperation of another individual.

Switching between sources, advancing fast fast-forward, rewinding, changing chapters, changing volume, etc., can be very cumbersome in a professional studio as well as in the home.

Similarly, traditional interfaces are not well suited for smaller, specialized electronic gadgets.

Additionally, people with motion impairment conditions find it very challenging to cope with traditional user interfaces and computer access systems.

These conditions and disorders are often accompanied by tremors, spasms, loss of coordination, restricted range of movement, reduced muscle strength, and other motion impairing symptoms.

As people age, their motor skills decline and impact the ability to perform many tasks.

It is known that as people age, their cognitive, perceptual and motor skills decline, with negative effects in their ability to perform many tasks.

The requirement to position a cursor, particularly with smaller graphical presentations, can often be a significant barrier for elderly or afflicted computer users.

However, at the same time, this shift in the user interaction from a primarily text-oriented experience to a point-and-click experience has erected new barriers between people with disabilities and the computer.

For example, for older adults, there is evidence that using the mouse can be quite challenging.

It has been shown that even experienced older computer users move a cursor much more slowly and less accurately than their younger counterparts.

In addition, older adults seem to have increased difficulty (as compared to younger users) when targets become smaller.

For older computer users, positioning a cursor can be a severe limitation.

One solution to the problem of decreased ability to position the cursor with a mouse is to simply increase the size of the targets in computer displays, which can often be counter-productive since less information is being displayed, requiring more navigation.

Previous studies indicate that users find gesture-based systems highly desirable, but that users are also dissatisfied with the recognition accuracy of gesture recognizers.

Furthermore, experimental results indicate that a user's difficulty with gestures is in part due to a lack of understanding of how gesture recognition works.

However, examples of perceptual user interfaces to date are dependent on significant limiting assumptions.

Proper operation of the system is dependent on proper lighting conditions and can be negatively impacted when the system is moved from one location to another as a result of changes in lighting conditions, or simply when the lighting conditions change in the room.

The use of such devices is generally found to be distracting and intrusive for the user.

Thus perceptual user interfaces have been slow to emerge.

The reasons include heavy computational burdens, unreasonable calibration demands, required use of intrusive and distracting devices, and a general lack of robustness outside of specific laboratory conditions.

For these and similar reasons, there has been little advancement in systems and methods for exploiting perceptual user interfaces.

However, as the trend towards smaller, specialized electronic gadgets continues to grow, so does the need for alternate methods for interaction between the user and the electronic device.

Many of these specialized devices are too small and the applications unsophisticated to utilize the traditional input keyboard and mouse devices.

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