Duplicate check image resolution

• US 9,202,146 B2
• Filed: 03/18/2014
• Issued: 12/01/2015
• Est. Priority Date: 01/04/2013
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Moon, Rodney G., Rector, Gerald C., Ridgway, Philip
• Primary Examiner(s): Patel, Nirav G
• Application Number:
  US14/217,703
• Publication Number:
  US 20140198968A1
• Time in Patent Office: 623 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06F 18/22 Matching criteria, e.g. proximity measures
• CPC Class Codes: G06T 3/00 Geometric image transformations in the plane of the image
• CPC Class Codes: G06T 3/40 Scaling of whole images or parts thereof, e.g. expanding or contracting
• CPC Class Codes: G06V 10/10 Image acquisition document image scanning and transmission H04N1/00; control of digital cameras H04N23/60
• CPC Class Codes: G06V 10/751 Comparing pixel values or logical combinations thereof, or feature values having positional relevance, e.g. template matching

Abstract

A system and method for comparing digital images, such as checks images used by banks, includes receiving and processing the images to be compared, including scaling the images to a common resolution, as well as filtering them to remove spot noise, background pels, and other non-information carrying elements. One or more regions of each image are selected for comparison. The selected regions are compared to one another by subtracting the pels of one image from the other'"'"'s pels. A determination is made of whether the two or more images are duplicates of one another, or depict a substantially identical subject, based on the results of the subtractions. Furthermore, the amount of filtering and scaling may be adjusted to enhance the effects of the system to take advantage of common characteristics that may be known or detected in a particular set of images to be compared.

Claims

1. A method for comparing images, comprising:

receiving a first image and a second image;

processing the first image and the second image using a program executable by a processor communicating with a computer, the processing of the first and the second image including scaling the first image and the second image to a common resolution and filtering at least one of the first image and the second image;

selecting one or more pel regions of the scaled first image and of the scaled second image;

subtracting the one or more selected pel regions of the scaled first image from the one or more selected pel regions of the scaled second image, respectively; and

determining whether the first image and the second image depict identical subjects based on the results of the subtraction,

wherein one or both of the first image and the second image are bitonal, having black pels and white pels, and the processing module is further configured to filter the first image and the second image by removing black pels or groups of black pels surrounded by white pels, and the black pels or groups of black pels exist in a square grid having the size 1 by 1 pels to 4 by 4 pels, preferably having the size 3 by 3 to 4 by 4 pels.

2. The method of claim 1, wherein the filtering of at least one image is recursive.

3. The method of claim 1, wherein the amount of filtering of the first image and of the second image is adjustable.

4. The method of claim 1, wherein the scaling of the first image and of the second image is adjustable.

5. The method of claim 1, wherein the processed first image and the processed second image are scaled to a common resolution between 91 and 100 pels per inch.

6. The method of claim 1, wherein the processed first image and the processed second image are scaled to a common resolution between 75 and 90 pels per inch.

7. The method of claim 1, wherein the first image and the second image are of negotiable instruments, including check images.