Matching of digital images to acquisition devices

• US 20060013434A1
• Filed: 07/13/2004
• Published: 01/19/2006
• Est. Priority Date: 07/13/2004
• Status: Active Grant

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Smith, Craig M., Reisch, Robert V.
• Granted Patent: US 7,609,846 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G06T 7/0008 checking presence/absence
• CPC Class Codes: H04N 1/32101 Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title
• CPC Class Codes: H04N 2201/3205 of identification information, e.g. name or ID code H04N2201/3209 takes precedence
• CPC Class Codes: H04N 2201/3235 Checking or certification of the authentication information, e.g. by comparison with data stored independently

Abstract

In a digital image matching method, reference calibration data associated with one or more reference digital image files is ascertained. The reference digital image files each have reference calibration data that is hidden metadata and can also have public metadata that is readable by a different procedure. A test digital image file is obtained and a data structure capable of holding the reference calibration data is detected in the test digital image file. The presence of second calibration data within the data structure of the test digital image file is determined. If the reference and second calibration data match, then the test digital image file and reference digital image files are from the same digital acquisition device.

Claims

1. A digital image matching method comprising the steps of:

ascertaining reference calibration data associated with one or more reference digital image files, said reference digital image files each having public metadata readable by a publicly available procedure, said reference calibration data being unreadable by said procedure, said reference calibration data having one or more reference values;

detecting a data structure in a test digital image file, said data structure being capable of holding said reference calibration data;

determining the presence of second calibration data within said data structure of said test digital image file, said second calibration data including at least one of said reference values.

2. The method of claim 1 wherein said determining further comprises searching said test digital image file.

3. The method of claim 2 further comprising reading said public metadata to provide public information and delimiting said searching utilizing said public information.

4. The method of claim 1 further comprising reading said public metadata to provide public information and utilizing said public information during said ascertaining.

5. The method of claim 1 wherein said ascertaining further comprises retrieving said reference calibration data from a previously unknown file location in said reference digital image files.

6. The method of claim 5 further comprising:

capturing said reference digital image files prior to said ascertaining; and

obtaining said test digital image file prior to said capturing.

7. The method of claim 1 wherein said reference calibration data includes a reference calibration value of each of a plurality of different color channels and said second calibration data includes at least one of said reference calibration values.

8. The method of claim 1 wherein said determining includes one or more of:

signature analysis, frequency evaluation associated with value/location analysis, data normalization, and adjacency analysis.

9. The method of claim 1 wherein said determining includes conducting pattern recognition.

10. The method of claim 1 wherein said ascertaining further comprises determining a file location of said reference calibration data and said determining further comprises searching for said second calibration data in the vicinity of said file location in said test digital image file.

11. The method of claim 10 wherein said public metadata identifies an acquisition device and said determining further comprises reading said public metadata and obtaining said file location for said acquisition device from a database.

12. The method of claim 1 wherein said second calibration data is at a location in said data structure of said test digital image corresponding to a location of said reference calibration data in a corresponding data structure of said reference digital image.

13. The method of claim 1 wherein said test digital image file has an unknown provenance and said reference digital image files have a known provenance.

14. A digital image matching method comprising the steps of:

ascertaining reference calibration data associated with a reference digital acquisition device, said reference calibration data including a calibration value of each of a plurality of different color channels;

detecting a data structure in a test digital image file, said data structure being capable of holding said reference calibration data;

determining the presence of second calibration data within said data structure of said test digital image file, said second calibration data including at least one of said calibration values.

15. The method of claim 14 wherein said determining further comprises searching said test digital image file.

16. The method of claim 14 wherein said second calibration data includes all of said calibration values.

17. The method of claim 14 wherein said data structure includes metadata unrelated to said second calibration data.

18. The method of claim 17 further comprising reading said metadata and delimiting said searching responsive to said reading.

19. The method of claim 17 further comprising reading said metadata to provide information and utilizing said information during said ascertaining.

20. The method of claim 14 wherein said reference calibration data is located in a plurality of reference digital image files.

21. The method of claim 20 wherein said ascertaining further comprises retrieving said reference calibration data from a previously unknown file location in said reference digital image files.

22. The method of claim 21 wherein said ascertaining further comprises capturing said reference digital image files using a plurality of different reference digital acquisition devices.

23. The method of claim 22 wherein said reference digital image files each have only one of said calibration values that is the same.

24. The method of claim 20 wherein said second calibration data is at a location in said data structure of said test digital image file corresponding to a location of said reference calibration data in corresponding data structures of said reference digital image files.

25. The method of claim 14 wherein said calibration data includes a normalized calibration value of one of said color channels.

26. The method of claim 14 wherein said color channels are red, blue, and green.

27. The method of claim 14 wherein each said calibration value has the same size, in number of bits.