Automated statistical self-calibrating detection and removal of blemishes in digital images dependent upon changes in extracted parameter values

• US 20080152255A1
• Filed: 02/25/2008
• Published: 06/26/2008
• Est. Priority Date: 09/30/2003
• Status: Active Grant

• Current Assignee: FotoNation Limited (Adeia Inc.)
• Original Assignee: FotoNation Vision Limited (Adeia Inc.)
• Inventors: Steinberg, Eran, Prilutsky, Yury, Zamfir, Adrian, Bigioi, Petronel, Corcoran, Peter, Buzuloiu, Vasile, Zamfir, Marta, Ursu, Danutz
• Granted Patent: US 7,545,995 B2
• Time in Patent Office: Days
• US Class Current: 382/275
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/155 Removing patterns interfering with the pattern to be recognised, such as ruled lines or underlines
• CPC Class Codes: H04N 1/4097 Removing errors due external factors, e.g. dust, scratches
• CPC Class Codes: H04N 23/811 by dust removal, e.g. from surfaces of the image sensor or processing of the image signal output by the electronic image sensor
• CPC Class Codes: H04N 25/683 by defect estimation performed on the scene signal, e.g. real time or on the fly detection

Abstract

A method of automatically correcting dust artifact within images acquired by a system including a digital camera includes determining that certain pixels correspond to dust artifact regions within a first digitally-acquired image. The dust artifact regions are associated with one or more extracted parameters relating to a variable optical system of the digital camera when the first image was acquired. An associated statistical dust map is formed including mapped dust regions based on known correspondence between effects on dust artifact data of values of extracted parameters. Pixels corresponding to correlated dust artifact regions within a second image acquired with said digital camera are corrected according to one or more different values of the extracted parameters relating to the variable optical system based on the associated statistical dust map.

Claims

1. A method of automatically correcting dust artifact within images acquired by a system including a digital camera, comprising:

(a) determining that certain pixels correspond to dust artifact regions within a first digitally-acquired image;

(b) associating the dust artifact regions with one or more extracted parameters relating to a variable optical system of said digital camera when the first image was acquired;

(c) forming an associated statistical dust map including mapped dust regions based on the dust artifact determining and associating operations and known correspondence between effects on dust artifact data of one or more different values of said one or more extracted parameters; and

(d) correcting pixels corresponding to correlated dust artifact regions within a second image acquired with said digital camera according to one or more different values of said one or more extracted parameters relating to said variable optical system based on said associated statistical dust map.