Image color balance for scanners using an illumination spectral sensor

• US 20030147110A1
• Filed: 01/31/2002
• Published: 08/07/2003
• Est. Priority Date: 01/31/2002
• Status: Active Grant

• Current Assignee: Kodak Alaris Inc (KPP (no. 2) Trustees Ltd.)
• Original Assignee: Eastman Kodak Company
• Inventors: Simmons, George O., Barton, Mark A.
• Granted Patent: US 7,251,065 B2
• Time in Patent Office: Days
• US Class Current: 358/509
• CPC Class Codes: H04N 1/603 controlled by characteristics of the picture signal generator or the picture reproducer
• CPC Class Codes: H04N 1/6086 by scene illuminant, i.e. conditions at the time of picture capture, e.g. flash, optical filter used, evening, cloud, daylight, artificial lighting, white point measurement, colour temperature

Abstract

An image scanning system for producing an electronic version of a hardcopy element which is compensated for spectral content of an illumination source in the image scanning system, the image scanning system includes a sensor for receiving light containing the hardcopy element for forming and storing an electronic version of the hardcopy element; a spectral sensor for receiving light from the illumination source and storing an electronic version of spectral contents of the illumination source; and a conversion system for receiving the electronic versions of the illumination source and the hardcopy element and creating a compensation table that compensates subsequent hardcopy elements passed through the conversion system.

Claims

1. An image scanning system for producing an electronic version of a hardcopy element which is compensated for spectral content of an illumination source in the image scanning system, the image scanning system comprising:

(a) a sensor for receiving light containing the hardcopy element for forming and storing an electronic version of the hardcopy element;

(b) a spectral sensor for receiving light from the illumination source and storing an electronic version of spectral contents of the illumination source; and

(c) a conversion system for receiving the electronic versions of the illumination source and the hardcopy element and adjusting one or more parameters of a compensation process that compensates subsequent hardcopy elements passed through the conversion system.

2. The scanning system as in claim 1, wherein the conversion system is created from the equations:

3. The scanning system in claim 1, wherein the conversion system includes as a table or LUT for implementation.

4. The scanning system as in claim 3, wherein the conversion system includes a mathematical scheme that interpolate entries in the LUT or table.

5. An image scanning system for producing an electronic version of a hardcopy element which is compensated for spectral content of an illumination source in the image scanning system, the image scanning system comprising:

(a) a sensor for receiving light containing the hardcopy element for forming and storing an electronic version of the hardcopy element;

(b) a conversion operator that compensates hardcopy the hardcopy element for the illumination source; and

(c) a conversion system for receiving the electronic versions of the illumination source and compensating the hardcopy element according to the conversion operator.

6. The scanning system as in claim 5, wherein the conversion operator is created from the equations:

7. The scanning system in claim 5 wherein the conversion operator includes LUT or table for implementation.

8. The scanning system as in claim 7, wherein the conversion operator includes a mathematical scheme that interpolate entries in the LUT or table.