Camera system for detecting codings

• US 10,798,296 B2
• Filed: 08/09/2019
• Issued: 10/06/2020
• Est. Priority Date: 08/14/2018
• Status: Active Grant

• Current Assignee: I F M Electronic GmbH
• Original Assignee: I F M Electronic GmbH
• Inventors: Olbrich, Ville, Kohlmann, Klaus, Prestele, Christian, Wilks, Ralph, Gebhard, Andreas
• Primary Examiner(s): Spinks, Antoinette T
• Application Number:
  US16/536,336
• Publication Number:
  US 20200059594A1
• Time in Patent Office: 424 Days
• CPC Class Codes: G06V 10/245 by locating a pattern; Special marks for positioning
• CPC Class Codes: G06V 10/44 Local feature extraction by analysis of parts of the pattern, e.g. by detecting edges, contours, loops, corners, strokes or intersections; Connectivity analysis, e.g. of connected components
• CPC Class Codes: G06V 30/2247 Characters composed of bars, e.g. CMC-7
• CPC Class Codes: H04N 23/61 based on recognised objects
• CPC Class Codes: H04N 23/62 Control of parameters via user interfaces
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 23/959 by adjusting depth of field during image capture, e.g. maximising or setting range based on scene characteristics
• CPC Class Codes: H04N 5/142 Edging; Contouring

Abstract

A method for operating a camera system for detecting codings, in which positions of contour points of the codings are determined in relation to edges of a search zone of the camera system, wherein a reading reliability of the search zone is determined from a distance of the contour points from the edges of the search zone.

Claims

1. A method for operating a stationary camera system for detecting codings applied to subjects, the method comprising:

moving the subjects past the camera system;

determining positions of contour points of the codings in relation to edges of a search zone of the camera system; and

determining a reading reliability of the search zone from a distance of the contour points from the edges of the search zone by detecting the codings of several of the subjects brought into the search zone.

2. The method according to claim 1, wherein the reading reliability of the search zone is classified as critical in a case in which a number of the contour point positions falling within a boundary region of the search zone exceeds a frequency limit value.

3. The method according to claim 1, further comprising determining a drift of the contour point positions over a plurality of detected contour point positions.

4. The method according to claim 1, further comprising adjusting the search zone based on the determined reading reliability.

5. The method according to claim 4, wherein the search zone is adjusted by enlarging a field of view of the camera system.

6. The method according to claim 4, wherein the search zone is adjusted by increasing a distance of a camera of the camera system to the subjects, and/or by shortening a focal length of a camera lens of the camera system or exchanging the camera lens with a different lens having a shorter focal length.

7. The method according to claim 1, wherein a position of a camera of the camera system, an aperture of the camera and/or a focus of a camera lens of the camera are selected or adjusted based on the reading reliability such that expected heights of the subjects and/or expected distances of the contour points of the codings fall within the search zone and within a predetermined depth of field range.

8. The method according to claim 1, further comprising adjusting an alignment of a camera of the camera system based on the determined positions of the contour points of the codings.

9. A camera system configured to carry out the method of claim 1.