METHOD AND APPARATUS FOR OPERATING INDICIA READING TERMINAL INCLUDING PARAMETER DETERMINATION

• US 20100078477A1
• Filed: 09/30/2008
• Published: 04/01/2010
• Est. Priority Date: 09/30/2008
• Status: Active Grant

• Current Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Original Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Inventors: Wang, Ynjiun P., Deng, Shulan
• Granted Patent: US 8,794,520 B2
• Time in Patent Office: Days
• US Class Current: 235/454
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10752 Exposure time control
• CPC Class Codes: G06K 7/10811 Focalisation

Abstract

A method for operating an indicia reading terminal is provided wherein image information can be processed for determining a location of a decodable indicia representation for a certain frame of image data, the result of the processing can be utilized for determination of an imaging parameter, the imaging parameter can be utilized for capture of a subsequent frame and the subsequent frame can be subject to image processing.

Claims

1. A method for operating an indicia reading terminal for decoding of a decodable indicia, said indicia reading terminal including an image sensor and an imaging lens assembly for focusing of an image of said decodable indicia onto said image sensor, said indicia reading terminal being operative to capture at a frame rate a succession of frames of image data, said method comprising the steps of:

(d) processing image information to determine a location of a decodable image representation in a certain frame of image data;

(e) determining an imaging parameter utilizing a result of said processing step (a); and

(f) utilizing said imaging parameter determined at step (b), capturing a subsequent frame of image data.

2. The method of claim 1, wherein said processing step (a) includes the step of storing a frame of image data into a CPU addressable memory.

3. The method of claim 1, wherein said processing step (a) includes the step of sampling image data along a plurality of sampling paths.

4. The method of claim 1, wherein said processing step (a) includes the step of sampling image data along one or more of a plurality of horizontal sampling paths and a plurality of vertical sampling paths.

5. The method of claim 1, wherein said processing step (a) includes the step of calculating an autocorrelation score for a sampling path.

6. The method of claim 1, wherein said processing step (a) includes selecting among the highest autocorrelation scores for a plurality of sampling paths.

7. The method of claim 1, wherein said processing step (a) is initiated responsively to an operator actuating a trigger of said indicia reading terminal.

8. The method of claim 1, wherein said processing step (a) includes the step of determining a plurality of locations including decodable indicia representations.

9. The method of claim 1, wherein said determining step (b) includes determining an exposure period parameter.

10. The method of claim 1, wherein said determining step (b) includes selectively utilizing image data at a location of said certain frame determined to include a decodable indicia representation.

11. The method of claim 1, wherein responsively to a trigger signal being made active by actuation of a trigger, said indicia reader captures a plurality of frames of image data including said certain frame and said subsequent frame, and wherein said certain frame and said subsequent frame are not successive frames.

12. The method of claim 1, wherein said processing step (a) includes processing completed prior to storage of said certain frame of image data into a CPU addressable memory.

13. The method of claim 1, wherein said method further includes the step of subjecting said subsequent frame to context detection.

14. The method of claim 1, wherein said method further includes the step of subjecting said subsequent frame to processing for parameter determination.

15. The method of claim 1, wherein said method further includes the step of subjecting at least one of said subsequent frame or a further subsequent frame to a decode attempt for decoding of decodable indicia.

16. The method of claim 1, wherein said method further includes the steps of repeating steps (a), (b), and (c) for a plurality of frames of image data so that a plurality of subsequent frames are captured, and subjecting at least one said subsequent frame of image data to a decode attempt.

17. A hand held indicia reading terminal for reading of a decodable indicia, said hand held indicia reading terminal comprising:

an image sensor;

an optics assembly focusing an image of said decodable indicia onto said image sensor;

a hand held housing encapsulating said image sensor, said hand held indicia reading terminal being adapted to capture a succession of frames of image data according to a frame rate such that each frame of said succession of captured frames is captured within a frame time;

a trigger disposed on said hand held housing for initiation of an indicia decode attempt;

wherein said hand held indicia reading terminal is operative for (a) processing a certain frame of a succession of frames for a period of less than said frame time for determining a location of a decodable indicia representation in said certain frame;

wherein said hand held indicia reading terminal is further operative for (b) utilizing a result of said processing (a) for determining an imaging parameter; and

wherein said hand held indicia reading terminal is further operative for (c ) utilizing said imaging parameter for capturing of a subsequent frame of image data.

18. The hand held indicia reading terminal of claim 17, wherein said processing (a) includes reading location data from a frame reference data location.

19. The hand held indicia reading terminal of claim b17, wherein said processing (a) includes applying texture filters to said certain frame.

20. The hand held indicia reading terminal of claim b17, wherein said processing (a) includes processing data along sampling paths of said certain frame.

21. A hand held indicia reading terminal for reading of a decodable indicia, said hand held indicia reading terminal comprising:

a two dimensional image sensor having a plurality of pixels arranged in columns and rows of pixels;

an optics assembly focusing an image of said decodable indicia onto said two dimensional image sensor;

a memory;

a central processing unit (CPU);

a trigger disposed on said hand held housing for initiation of an indicia decode attempt;

wherein said hand held indicia reading terminal is operative so that subsequent to said trigger being actuated, said hand held indicia reading terminal stores into said memory a succession of frames of image data for processing by said CPU, wherein said hand held indicia reading terminal is further operative so that said succession of frames are captured according to frame rate such that each of said frames of image data is captured within a frame time;

wherein said hand held indicia reading terminal is further operative so that subsequent to said trigger being actuated, said CPU subjects each of a plurality of said succession of frames to processing that includes determining a location of a decodable indicia representation in a frame of image data, and utilizing a result of said location determining for determining an imaging parameter for use in capture of a subsequent frame.

22. The hand held indicia reading terminal of claim 21, wherein said hand held indicia reading terminal is operative so that said processing by said CPU for each of said plurality of frames including processing for determining a location of a decodable indicia representation and utilizing a result of said location determining for determining an imaging parameter is restricted from consuming a time period for processing of greater than said frame time.

23. A hand held indicia reading terminal for reading of a decodable indicia, said hand held indicia reading terminal comprising:

an image sensor;

an optics assembly focusing an image of said decodable indicia onto said image sensor;

a hand held housing encapsulating said image sensor, said hand held indicia reading terminal being adapted to capture a succession of frames of image data;

wherein said indicia reading terminal is operative to utilize a determined location of a decodable indicia representation corresponding to said decodable indicia for frame capture so that said indicia reading terminal is capable of successfully decoding a decodable indicia disposed in a scene within a field of view of said indicia reading terminal, wherein said scene includes an energized red LED array substantially spanning said field of view, and a non-light transmissive substrate carrying said decodable indicia disposed over said red LED array at an arbitrary position over said red LED array within said field of view such that said non-light transmissive substrate encompasses less than 25% of said field of view, and a remaining portion of said field of view corresponds to said red LED array.