Marking physical objects and related systems and methods

• US 7,027,612 B2
• Filed: 09/11/2002
• Issued: 04/11/2006
• Est. Priority Date: 10/05/2001
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Lofgren, Neil E., Patterson, Philip R., McKinley, Tyler J.
• Primary Examiner(s): Wu, Jingge
• Assistant Examiner(s): Upreti, Ashutosh
• Application Number:
  US10/242,300
• Publication Number:
  US 20030118210A1
• Time in Patent Office: 1,308 Days
• Field of Search: None
• US Class Current: 382/100
• CPC Class Codes: G06Q 40/04 Trading; Exchange, e.g. stocks, commodities, derivatives or currency exchange
• CPC Class Codes: G08G 1/017 identifying vehicles G08G1/015, G08G1/054 take precedence
• CPC Class Codes: G08G 1/04 using optical or ultrasonic detectors

Abstract

The present invention provides techniques whereby objects are readily identified. These inventive techniques are ideally suited for traffic monitoring. In one implementation a vehicle is marked with a machine-readable code on an outer, top surface of the vehicle. An elevated or aerial platform captures an image of the vehicle. A detector analyzes the captured image to recover the machine-readable code. The vehicle is identified from such. Traffic congestion can be determined by monitoring the movement of a marked vehicle through the city traffic. In some implementations the machine-readable code comprises an identifier, which is used to interrogate a database for related information.

Claims

1. A method to uniquely identify a mobile object depicted in an image, wherein the image is captured from an elevated or aerial platform, said method comprising:

analyzing the image to detect machine-readable code associated with the depicted mobile object, wherein the mobile object is steganographically marked with the machine-readable code prior to image capture, and wherein the machine-readable code comprises an identifier;

decoding the machine-readable code to obtain the identifier; and

identifying the mobile object via the identifier.

2. The method of claim 1 wherein the machine-readable code comprises a digital watermark.

3. The method of claim 1 wherein the mobile-object is only semi-mobile, and the object comprises at least one of a beehive, tent and trailer.

4. The method of claim 1 further comprising linking to a data repository with at least the identifier.

5. The method of claim 4 wherein said identifying comprises accessing information stored in the data repository with the identifier to make an identification.

6. The method of claim 1 wherein the mobile object comprises a vehicle.

7. The method of claim 6 wherein the machine-readable code comprises an ink or paint having an predetermined fluorescing frequency band.

8. The method of claim 6 wherein the machine readable code comprises an ink or paint having an predetermined fluorescing decay time.

9. The method of claim 6 wherein the machine-readable code comprises steganographic markings.

10. A method of monitoring traffic comprising:

marking a vehicle which will travel on a road with machine-readable code, wherein the machine-readable code is provided on a vehicle surface so as to be detectable from aerial imagery captured of the marked vehicle, but remains generally imperceptible to a human observer of the vehicle, and wherein the machine-readable code comprises a plural-bit identifier;

capturing an image of the marked vehicle;

decoding the machine-readable code from a captured image to recover the plural-bit identifier; and

monitoring the vehicle based at least in part by the plural-bit identifier.

11. The method of claim 10, wherein once the vehicle has been identified, said method further comprises monitoring the vehicle'"'"'s progress in traffic in relation to a predetermined position or for a predetermined time period.

12. The method of claim 10, wherein once the vehicle has been identified, said method further comprises monitoring the vehicle'"'"'s speed with respect to a predetermined distance.

13. The method of claim 10, wherein said identifying comprises interrogating a data structure with the plural-bit identifier to access related information, wherein the related information is associated with the plural-bit identifier prior to image capture.

14. The method of claim 13 wherein the related information comprises at least one of vehicle movement history, vehicle ownership and a distance over which the vehicle will travel.

15. The method of claim 10, wherein the machine-readable code comprises a digital watermark.

16. The method of claim 10, wherein the marking is visually perceptible to a human observer of the marking.

17. The method of claim 10, wherein said marking is provided by subtly varying the surface texture of the vehicle surface to include the machine-readable code.

18. The method of claim 10 wherein said marking comprising at least a steganographic component which is visually imperceptible to a casual observer of the marking.

19. A method of identifying a vehicle comprising:

optically capturing an image of the vehicle from an aerial platform, wherein the vehicle includes a steganographically hidden marking that is hidden prior to image capture, and wherein the marking is hidden on a vehicle surface so as to be viewable from the aerial platform, and wherein the marking includes a plural-bit identifier;

analyzing the captured image to detect the steganographically hidden marking and to obtain the plural-bit identifier; and

identifying the vehicle based on the plural-bit identifier.

20. The method of claim 19 further comprising interrogating a data structure with the plural-bit identifier to access information associated with the vehicle.

21. The method of claim 19 wherein the steganographically hidden marking comprises a digital watermark.

22. The method of claim 19 wherein the marking is hidden by applying an ultraviolet or infrared ink to the vehicle surface that is viewable from the aerial platform, and wherein the plural-bit identifier comprises an emission frequency band of the ink.

23. The method of claim 19 wherein the steganographic signal is redundantly embedded across the vehicle surface.

24. A mobile vehicle comprising an outer surface having a machine-readable code provided thereon, wherein the machine-readable code is generally imperceptible to human viewers of the vehicle, and wherein the machine-readable code is detectable from analysis of optical scan data, wherein the machine-readable code serves to uniquely identify the vehicle from aerial imagery including the vehicle.

25. The vehicle of claim 24 wherein the machine-readable code comprises a steganographic marking.

26. The vehicle of claim 24 wherein the machine-readable code is detectable from visible light scan data.

27. The vehicle of claim 24 wherein the machine-readable code comprises digital watermarking.

28. The vehicle of claim 24 wherein the machine-readable code is detectable from non-visible light scan data.

29. The vehicle of claim 24 wherein the code comprises plural-bits.