Calibrating of interactive touch system for image compositing

• US 8,330,730 B1
• Filed: 08/29/2008
• Issued: 12/11/2012
• Est. Priority Date: 09/04/2007
• Status: Expired due to Fees

• Current Assignee: Imaging Systems Technology Incorporated
• Original Assignee: Imaging Systems Technology Incorporated
• Inventors: Pavliscak, Thomas J., Wedding, Carol Ann, Kurtz, Victoria Wedding, Afzal, Rebecca
• Primary Examiner(s): Cerullo, Liliana
• Application Number:
  US12/200,951
• Time in Patent Office: 1,565 Days
• Field of Search: 348/592, 348/207.99, 3482071-20813, 345156-184
• US Class Current: 345/173
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: H04N 5/222 Studio circuitry; Studio devices; Studio equipment cameras or camera modules comprising electronic image sensors, or control thereof H04N23/00
• CPC Class Codes: H04N 5/272 Means for inserting a foreground image in a background image, i.e. inlay, outlay
• CPC Class Codes: H04N 9/75 Chroma key

Abstract

A chroma-key/matte display screen system with a touch input device that allows a user to interact with the display by selecting or pointing to composite images on the display. Touch input devices include camera based, infrared, membrane, and acoustic. Displays screens include CRT, various flat screen displays such as plasma, LCD, OLED, and various projection display systems.

Claims

1. A method of calibrating a touch system comprising a matte/chroma-key blue-screen composite imaging processing system and touch input device having an active touch area which comprises:

positioning the touch input device on a matte/chroma-key backdrop such that the active touch area of the touch input device is in a known location with reference to an imaging camera and composite image field of view,

illuminating a fiducial perimeter of the active touch area by a synchronized pulsed light emission of four laser sources for a time duration of less than one frame exposure time long to obtain laser flash fiducial images,

selecting one image frame containing a laser flash fiducial image of the touch system active touch area fiducial perimeter,

subjecting the laser flash fiducial image to recognition software analysis to derive a position of the illuminated fiducial perimeter of the active touch area,

retrieving appropriate calibration template files from memory, and

comparing the calibration template files to a size and position of the active touch area laser flash fiducial image

selecting and loading the calibration template file that matches the laser flash fiducial image, and

completing the calibration.

2. The method of claim 1 wherein one or more predefined calibration factors are stored in memory and accessed by an application program.

3. The method of claim 1 wherein calibration factors are derived that correlate the positioning of the touch input device active touch area to the image of the touch input device active touch area within a foreground camera field of view as viewed through the matte/chroma-key image composite.

4. The method of claim 1 wherein selected areas within the touch input device active touch area are programmed to function as touch system command keys that communicate pre-programmed operational commands to the system.

5. The method of claim 4 wherein the location of touch command keys are made visible to a presenter as a slightly different shade of color from that of the blue-screen background, the different shade being within the operational range of the matte/chroma-key blue-screen composite imaging processing system.

6. The method of claim 1 wherein multiple touch command keys are programmed at selected locations within the active touch area.

7. The method of claim 1 wherein a set of touch command keys are duplicated in multiple locations within the touch input device active touch area.

8. The method of claim 1 wherein the touch input device active touch area is an infrared device, an acoustic device, a surface capacitive device or a surface acoustic wave device.

9. The method of claim 1 wherein the touch input device active touch area is a bending wave device, an active digitizer device, a photo sensor device, a polymer waveguide device, a distributed light device, a multi-touch device, a laser-point touch device, or a projected capacitive device.

10. The method of claim 1 wherein the touch input device is an infrared touch input device, the infrared touch input device comprising four rigid strips each at right angles to one another so as to define the active touch area of the touch input device.

11. The method of claim 10 wherein printed circuit boards with infrared light emitting diode sensors and emitters are mounted on the rigid strips.

12. The method of claim 10 wherein the strips are mounted on the matte/chroma-key backdrop surface.

13. The method of claim 12 wherein the strips are coated with chroma-key/matte compatible color.

14. The method of claim 11 wherein the light emitting diode sensors in the printed circuit boards are recessed slightly in a frame to reduce the interference of ambient light.

15. A method of calibrating a touch system comprising a matte/chroma-key blue-screen composite imaging processing system and a touch input device having an active touch area, which comprises:

positioning the touch input device on a matte/chroma-key backdrop such that the active touch area input device is in a known location with reference to an imaging camera and composite field of view,

matching predefined calibration factors to touch input device active area fiducial marks with respect to the camera and composite image frame field of view, wherein the matching predefined calibration factors comprises;

illuminating a fiducial perimeter of the active touch area by a synchronized pulsed light emission of four laser sources for a time duration of less than one frame exposure time long to obtain laser flash fiducial images,

selecting one image frame containing a laser flash fiducial image of the touch system active touch area fiducial perimeter,

subjecting the laser flash fiducial image to recognition software analysis to derive a position of the illuminated fiducial perimeter of the active touch area,

retrieving appropriate calibration template files from memory, and

comparing calibration template files to a size and position of the active touch area laser flash fiducial image,

selecting and loading the calibration template file that matches the laser flash fiducial image, and

completing the calibration.

16. The method of claim 15 wherein the touch input device active touch area is an infrared device, an acoustic device, a surface capacitive device or a surface acoustic wave device.

17. The method of claim 15 wherein the touch input device active touch area is a bending wave device, an active digitizer device, a photo sensor device, a polymer waveguide device, a distributed light device, a multi-touch device, a laser-point touch device, or a projected capacitive device.

18. The method of claim 15 wherein the touch input device is an infrared touch input device, the infrared touch input device comprising four rigid strips each at right angles to one another so as to define the active touch area of the touch input device.

19. The method of claim 18 wherein printed circuit boards with infrared light emitting diode sensors and emitters are mounted on the rigid strips.