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Showing papers by "Gary Bradski published in 1998"


Proceedings ArticleDOI
Gary Bradski1
19 Oct 1998
TL;DR: An efficient, new algorithm is described here based on the mean shift algorithm, which robustly finds the mode (peak) of probability distributions within a video scene and is used as an interface for games and graphics.
Abstract: As a step towards a perceptual user interface, an object tracking algorithm is developed and demonstrated tracking human faces. Computer vision algorithms that are intended to form part of a perceptual user interface must be fast and efficient. They must be able to track in real time and yet not absorb a major share of computational resources. An efficient, new algorithm is described here based on the mean shift algorithm. The mean shift algorithm robustly finds the mode (peak) of probability distributions. We first describe histogram based methods of producing object probability distributions. In our case, we want to track the mode of an object's probability distribution within a video scene. Since the probability distribution of the object can change and move dynamically in time, the mean shift algorithm is modified to deal with dynamically changing probability distributions. The modified algorithm is called the Continuously Adaptive Mean Shift (CAMSHIFT) algorithm. CAMSHIFT is then used as an interface for games and graphics.

676 citations


Patent
Gary Bradski1
15 May 1998
TL;DR: In this paper, a tracking method using a probability distribution of the desired object is presented, where the method operates by first calculating a mean location of a probability distributions within a search window, and then the search window is centered on the calculated mean location.
Abstract: A tracking method is disclosed. The method of the present invention tracks a object using a probability distribution of the desired object. The method operates by first calculating a mean location of a probability distribution within a search window. Next, the search window is centered on the calculated mean location. The steps of calculating a mean location and centering the search window may be performed until convergence. The search window may then be resized. Successive iterations of calculating a mean, centering on the mean, and resizing the search window track an object represented by the probability distribution. In one embodiment, a flesh hue probability distribution is generated from an input video image. The flesh hue probability distribution is used to track a human head within the video image.

63 citations


Patent
01 Dec 1998
TL;DR: In this paper, the authors present a computerized system that includes a video camera and a controller that generates control variables having sensitivity to movement of the object that varies in accordance with movement of an object from a neutral position.
Abstract: The generation of control variables for computer vision is disclosed. In one embodiment of the invention, a computerized system includes a video camera and a controller. The video camera tracks an object, such as the head of a user of the computer. The controller generates control variables having sensitivity to movement of the object that varies in accordance with movement of the object from a neutral position.

23 citations


Patent
Gary Bradski1, Ryan A. Boller1
01 Dec 1998
TL;DR: In this paper, a computerized system consisting of a sensor, a controller, a utility and an application is described. And the controller generates control variables in response to the external events, such as audio and video events.
Abstract: Synthesizing computer input events is disclosed. In one embodiment, a computerized system includes a sensor, a controller, a utility and an application. The sensor detects external events, such as audio events and video events. The controller generates control variables in response to the external events. The utility synthesizes input events, such as joystick, mouse, and keyboard events, from the control variables. The application then utilizes these input events.

19 citations


Proceedings ArticleDOI
TL;DR: This article describes the use of gesture recognition techniques in computer vision, as a natural interface for video content navigation, and the design of a navigation and browsing system, which caters to these natural means of computer-human interaction.
Abstract: This article describes the use of gesture recognition techniques in computer vision as a natural interlace for video content navigation, and the design of a navigation andbrowsing system that caters to these natural means of computer-human interaction. For consumer applications, video content navigation presents two challenges: (1) howto parse and summarize multiple video streams in an intuitive and efficient manner, and (2) what type of interface will enhance the ease of use for video browsing andnavigation in a living room setting or an interactive environment. In this paper, we address the issues and propose the techniques that combine video content navigation with gestures, seamlessly and intuitively, in an integrated system. The current framework can incorporate speech recognition technology. We present a new type ofbrowser for browsing and navigating video content, as well as a gesture recognitioninterface for this browser. Keywords: Computer vision, pattern recognition, user interface, video content

18 citations


01 Jan 1998
TL;DR: This paper presents a new type of browser for browsing and navigating video content, as well as a gesture and speech recognition interface for this browser.
Abstract: This article describes ongoing research in the use computer vision gesture and speech recognition techniques as a natural interface for video content navigation, and the design of a navigation and browsing system that caters to these natural means of computer-human interaction. For consumer applications, video content navigation presents two challenges: (1) how to parse and summarize multiple video streams in an intuitive and efficient manner, and (2) what type of interface will enhance the ease of use for video browsing and navigation in a living room setting or an interactive environment. In this paper, we address the issues and propose the techniques that combine video content navigation with gesture and speech recognition, seamlessly and intuitively, in an integrated system. We present a new type of browser for browsing and navigating video content, as well as a gesture and speech recognition interface for this browser.

2 citations