Correcting exposure and tone scale of digital images captured by an image capture device

• US 6,473,199 B1
• Filed: 12/18/1998
• Issued: 10/29/2002
• Est. Priority Date: 12/18/1998
• Status: Expired due to Term

• Current Assignee: Monument Peak Ventures, LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: Eastman Kodak Company
• Inventors: Grady, Barbara L., Gilman, Paul B.
• Primary Examiner(s): Grant, II, Jerome
• Application Number:
  US09/215,733
• Time in Patent Office: 1,411 Days
• Field of Search: 358/518, 358/520, 358/521, 358/1.9, 358/530
• US Class Current: 358/1.9
• CPC Class Codes: H04N 1/407 Control or modification of tonal gradation or of extreme levels, e.g. background level
• CPC Class Codes: H04N 1/6033 using test pattern analysis H04N1/6055 takes precedence

Abstract

A method for correcting for exposure in a digital image which was captured by an image capture device and which is to be printed on a printer which forms monochrome or color images, on a medium, includes providing a plurality of exposure and tone scale correcting nonlinear transforms, each such nonlinear transform being unique to an exposure condition and which corrects exposure and tone scale for a digital image captured by the capture device for such unique exposure conditions and to be printed by the printer; and selecting the appropriate nonlinear transform from the plurality of nonlinear transforms and using such selected transform to transform the digital image and produce a new digital image which is corrected for exposure and tone scale when printed from the printer.

Claims

1. A method for correcting for exposure in a digital image which was captured by an image capture device and which is to be printed on a printer which forms monochrome or color images, on a medium, comprising the steps of:

a) providing a plurality of exposure and tone scale correcting transforms, each such transform being unique to an exposure condition and which corrects exposure and tone scale for a digital image captured by the capture device for such unique exposure conditions and to be printed by the printer; and

b) selecting the appropriate transform from the plurality of transforms and using such selected transform to transform the digital image and produce a new digital image which is corrected for exposure and tone scale when printed from the printer.

2. A method for correcting for exposure in a digital image which was captured by an image capture device and which is to be printed on a printer which forms monochrome or color images, on a medium, comprising the steps of:

a) providing a plurality of exposure and tone scale correcting nonlinear transforms, each such nonlinear transform being unique to an exposure condition and which corrects exposure and tone scale for a digital image captured by the capture device for such unique exposure conditions and to be printed by the printer; and

b) selecting the appropriate nonlinear transform from the plurality of nonlinear transforms and using such selected transform to transform the digital image and produce a new digital image which is corrected for exposure and tone scale when printed from the printer.

3. A method for correcting for exposure in a digital image which was captured by an image capture device and which is to be printed on a printer which forms monochrome or color images, on a medium, comprising the steps of:

a) providing a plurality of exposure and tone scale correcting nonlinear transforms, each such nonlinear transform being unique to an exposure condition and which corrects exposure and tone scale for a digital image captured by the capture device for such unique exposure conditions and to be printed by the printer;

b) selecting a nonlinear transform from the plurality of nonlinear transforms and using such selected transform to transform the digital image and produce a new digital image which is corrected for exposure and tone scale when printed from the printer; and

c) repeating step b) until a user acceptable print is produced.

4. A method for correcting for exposure in a digital image which was captured by an image capture device and which is to be printed on a printer which forms monochrome or color images, on a medium, comprising the steps of:

a) providing a plurality of exposure and tone scale correcting nonlinear transforms, each such nonlinear transform being unique to an exposure condition and which corrects exposure and tone scale for a digital image captured by the capture device for such unique exposure conditions and to be printed by the printer;

b) selecting a nonlinear transform from the plurality of nonlinear transforms and using such selected transform to transform the digital image;

c) correcting the transformed digital image to produce a new digital image which is corrected for exposure, tone scale, neutral balance and color reproduction when printed from the printer;

d) using the printer to print the color corrected transform digital image by the printer; and

e) repeating steps b), c), and d) until a user acceptable print is produced.

5. The method of claim 4 wherein the image capture device is a digital camera and the medium is a thermal print medium.

6. The method of claim 4 wherein the printer is an ink jet printer.

7. The method of claim 4 wherein the printer is an electrophotographic printer.

8. A computer program product comprising a computer readable storage medium, including a transform made by the steps of:

a) providing a plurality of exposure and tone scale correcting nonlinear transforms, each such nonlinear transform being unique to an exposure condition and which corrects exposure and tone scale for a digital image captured by the capture device for such unique exposure conditions and to be printed by the printer; and

b) selecting the appropriate nonlinear transform from the plurality of nonlinear transforms and using such selected transform to transform the digital image and produce a new digital image which is corrected for exposure and tone scale when printed from the printer.