US 7,321,687 B2
Apparatus and method for image processing to label an object in a binary image
Kunihiro Yamamoto, Kanagawa (Japan)
Assigned to Canon Kabushiki Kaisha, Tokyo (Japan)
Filed on Feb. 28, 2003, as Appl. No. 10/375,195.
Claims priority of application No. 2002-062299 (JP), filed on Mar. 07, 2002; application No. 2002-188352 (JP), filed on Jun. 27, 2002; and application No. 2002-188353 (JP), filed on Jun. 27, 2002.
Prior Publication US 2003/0169921 A1, Sep. 11, 2003
Int. Cl. G06K 9/00 (2006.01); G06K 9/34 (2006.01)
U.S. Cl. 382—170  [382/171; 382/174] 14 Claims
OG exemplary drawing
 
1. An image processing method for labeling an object in a binary image, comprising:
a black block detection step of, in said binary image, detecting as a black block a block of a predetermined size having a number of black pixels therein equal to or higher than a predetermined ratio; and
a label replacement step of replacing a pixel connection area with a predetermined label value, wherein the pixel connection area is started from the black block detected in said black block detection step;
wherein said label replacement step includes a step of starting the replacement at the detected black block when the black block is detected in said black block detection step, and wherein, in a case in which said black blocks of the predetermined size are not discovered in said binary image, said black block detection step detects the black block of a smaller size than the predetermined size.