Producing a defective pixel map from defective cluster pixels in an area array image sensor

• US 20030179418A1
• Filed: 03/19/2002
• Published: 09/25/2003
• Est. Priority Date: 03/19/2002
• Status: Abandoned Application

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Newhouse, Mark A., Meisenzahl, Eric J., McGarvey, James E., Wengender, Timothy G.
• Application Number:
  US10/100,723
• Publication Number:
  US 20030179418A1
• Time in Patent Office: Days
• US Class Current: 358/437
• CPC Class Codes: H04N 1/401 Compensating positionally unequal response of the pick-up or reproducing head H04N1/403 takes precedence
• CPC Class Codes: H04N 25/68 applied to defects

Abstract

A method for determining one or more defective pixels in an area array image sensor wherein such defects can form a defective cluster and for producing a defect map which can be used in a digital camera for image correction includes capturing a digital image using the image sensor and storing such digital image in a memory; identifying a plurality of defective pixels which form a defective cluster in the digital image by processing the digital image data using a localized averaging filter; and forming a map identifying the location of the defective cluster in the digital image.

Claims

1. A method for determining one or more defective pixels in an area array image sensor wherein such defects can form a defective cluster and for producing a defect map which can be used in a digital camera for image correction, comprising the steps of:

a) capturing a digital image using the image sensor and storing such digital image in a memory;

b) identifying a plurality of defective pixels which form a defective cluster in the digital image by processing the digital image data using a localized averaging filter; and

c) forming a map identifying the location of the defective cluster in the digital image.

2. The method of claim 1 wherein the image sensor is a full frame CCD image sensor.

3. The method of claim 1 wherein the location of the defective cluster is identified by identifying the location of each detective pixel in the defective cluster.

4. The method of claim 1 further including the step of storing the map in a digital camera and using the map to correct the defective clusters.

5. The method of claim 4 wherein the map provides the locations of correction pixels to be used to correct the defective clusters.

6. The method of claim 1 wherein the localized averaging filter is a localized mean value.

14. A computer program product comprising a computer readable storage medium having a computer program stored thereon for implementing the method of claim 1.

7. A method for determining a defect map for an area array image sensor wherein such defects can form a defective cluster and wherein such defect map can be used in a digital camera for image correction, comprising the steps of:

a) capturing a digital image using the image sensor and storing such digital image in a memory;

b) identifying at least two pixels forming a defective cluster in the digital image which have corrupted data by processing the digital image data using a localized averaging filter; and

c) forming a map of the defective cluster pixels.

8. The method of claim 7 further including correcting in the digital camera the defective cluster pixels, by the steps of:

d) using the map to identify the locations of correction pixels to be used to correct such corrupt data; and

e) using the correction pixels to correct such defective cluster pixels.

9. The method of claim 8 wherein the pixels are corrected using an average of the identified correction pixels and replacing each defective pixel value with a corrected pixel value.

10. The method of claim 7 wherein the output of the localized averaging filter is compared to a threshold determined from the digital image data.

11. The method of claim 7 wherein the image sensor is a color image sensor, and step b) is performed on separate color plane image data.

13. The method of claim 7 wherein the localized averaging filter is a localized mean value.