CAMERA CONTROL SYSTEM TO FOLLOW MOVING OBJECTS

• US 20100245589A1
• Filed: 03/31/2010
• Published: 09/30/2010
• Est. Priority Date: 05/15/2002
• Status: Abandoned Application

• Current Assignee: Rhode Island Board of education (STATE OF RHODE ISLAND)
• Original Assignee: Rhode Island Board of education (STATE OF RHODE ISLAND)
• Inventors: Guo, Yu, Sun, Ying
• Application Number:
  US12/751,282
• Publication Number:
  US 20100245589A1
• Time in Patent Office: Days
• US Class Current: 348/169
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51
• CPC Class Codes: G06T 7/66 of image moments or centre of gravity
• CPC Class Codes: G06V 10/147 Details of sensors, e.g. sensor lenses fingerprint or palmprint sensors G06V40/13; vascular sensors G06V40/145; eye sensors G06V40/19
• CPC Class Codes: G06V 10/24 Aligning, centring, orientation detection or correction of the image

Abstract

The present invention is directed to an image tracking system that tracks the motion of an object. The image processing system tracks the motion of an object with an image recording device that records a first image of an object to be tracked and shortly thereafter records a second image of the object to be tracked. The system analyzes data from the first and the second images to provide a difference image of the object, defined by a bit map of pixels. The system processes the difference image to determine a threshold and calculates a centroid of the pixels in the difference image above the threshold. The system then determines the center of the difference image and determines a motion vector defined by the displacement from the center to the centroid and determines a pan tilt vector based on the motion vector and outputs the pan tilt vector to the image recording device to automatically track the object.

Claims

1. A method for tracking the motion of an object with an image recording device that comprises:

recording a first image of an object to be tracked;

recording a second image of said object to be tracked;

analyzing data from said first and second images to provide a difference image of said object, said difference image comprised of pixels;

thresholding said difference image to provide a threshold;

calculating the centroid of said pixels above the threshold;

determining the center of said difference image;

determining a motion vector from the displacement from said center to said centroid;

determining a pan tilt vector based on said motion vector; and

moving the image receiving device based on said pan tilt vector to track the object.

2. The method of claim 1 wherein said recording a first image, said recording a second image, said analyzing, said thresholding, said calculating, said determining the center, said determining a motion vector and said determining a pan tilt vector are performed in a closed loop.

3. A system for tracking the motion of an object in real-time which comprises:

a camera that captures a first image of an object to be tracked and a second image of said object to be tracked;

means for analyzing said first and second images to provide a difference image, said difference image comprised of pixels;

means for thresholding said difference image to provide a threshold;

means for calculating the centroid of said pixels;

means for determining a motion vector defined by the displacement from the center of said difference image to said centroid;

means for determining a pan tilt vector based on said motion vector; and

means for moving said camera based on said pan tilt vector to track the object.