A device and method for performing optical character recognition

Patent metadata

Field	Value
Publication number	US-2017154232-A1
Application number	US-201515324506-A
Country	US
Kind code	A1
Filing date	Jul 9, 2015
Priority date	Jul 10, 2014
Publication date	Jun 1, 2017
Grant date	—

Abstract

A method of performing character isolation in an optical character recognition process, the method comprising receiving image data representing one or more character columns, determining a number of black pixels in each column of the image data, defining a vertical separation threshold which is a maximum number of black pixels in a column, dividing the columns into different pixel groups and groups of excluded columns by excluding any columns with a number of black pixels below the vertical separation threshold, identifying the pixel group representing the left most character column in the image data, determining whether there are one or two pixel groups representing character columns in the image data and, if it is determined that there are two pixel groups representing character columns, using a predetermined width value for a right most character column in order to identify a right hand boundary of the right most character column.

First claim

1 . A method of performing character isolation in an optical character recognition process, the method comprising:
receiving image data representing one or more character columns; determining a number of black pixels in each column of the image data; defining a vertical separation threshold which is a maximum number of black pixels in a column; dividing the columns into different pixel groups and groups of excluded columns by excluding any columns with a number of black pixels below the vertical separation threshold; identifying the pixel group representing the left most character column in the image data; determining whether there are one or two pixel groups representing character columns in the image data; and if it is determined that there are two pixel groups representing character columns, using a predetermined width value for a right most character column in order to identify a right hand boundary of the right most character column.

2 . A method according to clam 1 , wherein identifying the pixel group representing the left most character column in the image data comprises identifying the pixel group immediately to the right of the left most group of excluded columns.

3 . A method according to clam 1 , wherein identifying pixel group representing the left most character column in the image data comprises excluding the pixel group immediately to the right of the left most group of excluded columns if it is below a minimum digit width threshold such that the second pixel group to the right of the left most group of excluded columns is defined as the left most character column in the image data.

4 . A method according to any of claims 1 to 3 , wherein determining whether there are one or two pixel groups representing character columns in the image data comprises determining the width of the left most group of excluded columns.

5 . A method according to claim 4 , wherein if it is determined that the width of the left most group of excluded columns is below a maximum left margin threshold value, determining that there are two pixel groups representing character columns in the image data.

6 . A method according to any preceding claim, the method further comprising determining the width of the left most character column in the image data.

7 . A method according to claim 6 , the method further comprising using the determined width of the left most character column in the image data to determine whether the left most character column comprises exclusively narrow numbers or includes wide numbers.

8 . A method according to claim 7 , wherein if it is determined that the left most character column comprises exclusively narrow numbers, setting the maximum valid dose result to “19”.

9 . A method according to any preceding claim, the method further comprising excluding any pixel group touching the left hand border of the image.

10 . A method according to any preceding claim, the method further comprising indentifying a left hand boundary of the right hand character column by identifying a group of excluded columns located between the left hand and right hand character columns.

11 . A method according to any preceding claim, the method further comprising determining if the left hand character column is wider than a maximum digit width threshold value and if so, determining that numbers in the image data are in the range 8 to 10.

12 . A processor for performing character isolation in an optical character recognition process, the processor configure to:
receive image data representing one or more character columns; determine a number of black pixels in each column of the image data; define a vertical separation threshold which is a maximum number of black pixels in a column; divide the columns into different pixel groups and groups of excluded columns by excluding any columns with a number of black pixels below the vertical separation threshold; identify the pixel group representing the left most character column in the image data; determine whether there are one or two pixel groups representing character columns in the image data; and if it is determined that there are two pixel groups representing character columns, use a predetermined width value for a right most character column in order to identify a right hand boundary of the right most character column.

13 . A processor according to claim 12 , wherein the processor is configured to indentify the pixel group representing the left most character column in the image data by identifying the pixel group immediately to the right of the left most group of excluded columns.

14 . A processor according to claim 12 or claim 13 , wherein the processor is configured to determine whether there are one or two pixel groups representing character columns in the image data by determining the width of the left most group of excluded columns.

15 . A supplemental device for attachment to an injection device, the supplemental device comprising:
an imaging arrangement configured to capture an image of one or more numbers present on a moveable component of the injection device; and a processor according to any of claims 12 to 14 .

Assignees

• Sanofi Aventis Deutschland

Inventors

• Hammen Dietmar

Classifications

• G06V30/15

  Cutting or merging image elements, e.g. region growing, watershed or clustering-based techniques · CPC title

• G06V30/1423 Primary

  the instrument generating sequences of position coordinates corresponding to handwriting (preprocessing or recognising digital ink G06V30/32) · CPC title

• G06V30/10

  Character recognition · CPC title

• G06K9/222 Primary

  Physics · mapped topic

• G06K2209/01

  Physics · mapped topic