Generation of a typical image restored from a set of several images showing the same element

• US 20040252866A1
• Filed: 06/09/2004
• Published: 12/16/2004
• Est. Priority Date: 06/10/2003
• Status: Abandoned Application

• Current Assignee: STMicroelectronics SA (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SA (STMicroelectronics NV)
• Inventors: Tisse, Christel-Loic, Petitjean, Guillaume
• Application Number:
  US10/864,162
• Publication Number:
  US 20040252866A1
• Time in Patent Office: Days
• US Class Current: 382/117
• CPC Class Codes: G06F 18/28 Determining representative reference patterns, e.g. by averaging or distorting; Generating dictionaries
• CPC Class Codes: G06V 10/751 Comparing pixel values or logical combinations thereof, or feature values having positional relevance, e.g. template matching
• CPC Class Codes: G06V 40/18 Eye characteristics, e.g. of the iris

Abstract

A method for generating a typical image including at least three values per pixel, based on a set of binary images all showing a same element, including: summing up the binary values of the pixels of same coordinates in the set of binary images; generating a first state in the typical image if the sum of the pixels of same coordinates of the binary images provides a value smaller than a first threshold; and generating a second state in the typical image if the sum of the pixels of same coordinates of the binary images provides a value greater than a second threshold.

Claims

1. A method for generating a typical image comprising at least three values per pixel, based on a set of binary images all showing a same element, comprising:

summing up the binary values of the pixels of same coordinates in the set of binary images;

generating a first state in the typical image if the sum of the pixels of same coordinates of the binary images provides a value smaller than a first threshold; and

generating a second state in the typical image if the sum of the pixels of same coordinates of the binary images provides a value greater than a second threshold.

2. The method of claim 1, wherein the first threshold ranges between 0 and n/4, where n designates the number of binary images.

3. The method of claim 1, wherein the second threshold ranges between 3n/4 and 1, where n designates the number of binary images.

4. The method of claim 1, wherein the first and second thresholds are respectively 0 and 1.

5. The method of claim 4, wherein the restored typical image contains, for each pixel, the value of the sum of the pixels of the original images.

6. The method of claim 1, wherein the restored typical image contains a value representing an undetermined state for each pixel, said sum of which ranges between said thresholds.

7. A method for comparing a current image with a reference image, wherein at least one of the images is a typical image obtained by the implementation of the method of claim 1.

8. The method of claim 7, wherein the images originate from digital views of the iris of an eye.