Indicia reading terminal including frame quality evaluation processing

• US 10,296,770 B2
• Filed: 05/24/2018
• Issued: 05/21/2019
• Est. Priority Date: 10/31/2008
• 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
• Primary Examiner(s): Lee, Michael G
• Assistant Examiner(s): Tardif, David
• Application Number:
  US15/988,057
• Publication Number:
  US 20180268180A1
• Time in Patent Office: 362 Days
• Field of Search: 23547201
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10851 Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device basic electronic circuitry H03
• CPC Class Codes: G06K 7/1092 sensing by means of TV-scanning
• CPC Class Codes: G06K 7/1443 locating of the code in an image

Abstract

There is described an indicia reading terminal that can be operative to capture a succession of frames of image data and that can be operative so that a certain frame of the succession of frames is subject to quality evaluation processing where a result of the quality evaluation processing is responsive to one or more of an incidence and sharpness of edge representations of the frame of image data.

Claims

1. An indicia reader comprising:

an image sensor;

a processor communicatively coupled to the image sensor, wherein the processor is configured for;

capturing a succession of frames of image data with the image sensor;

processing a certain frame of the succession of frames to evaluate its frame quality based on at least one frame quality parameter;

determining whether the evaluated frame quality satisfies a first predetermined criteria;

while processing the certain frame, attempting to decode a previous frame within the succession of frames captured prior to the certain frame; and

if the certain frame satisfies the first predetermined criteria, ceasing the attempt to decode the previous frame.

2. The indicia reader of claim 1, wherein the succession of frames of image data comprises one of full frames, windowed frames, and a combination of full and windowed frames.

3. The indicia reader of claim 1, wherein the processor is capable of storing the succession of frames of image data and a result of quality evaluation of the succession of frames in a non-volatile memory.

4. The indicia reader of claim 3, wherein the processor, on failure of an attempt to decode, selects a frame of the succession of frames of image data stored in the non-volatile memory with highest quality score for decoding.

5. The indicia reader of claim 1, wherein the processor is configured for, when processing the certain frame to evaluate its frame quality, applying an edgelet filter.

6. The indicia reader of claim 1, wherein the processor is configured for, when processing the certain frame to evaluate its frame quality, calculating an autocorrelation score for a sampling path.

7. The indicia reader of claim 1, wherein the first predetermined criteria comprises:

a certain frame has a higher quality parameter than the previous frame being decoded;

a certain frame has a quality parameter score that is greater than that of the previous frame being decoded by a predetermined threshold.

8. The indicia reader of claim 1, wherein the processor is configured for, when processing the certain frame to evaluate its frame quality, determining if the certain frame has a white level within a predetermined range, wherein the white level is calculated by selectively utilizing a pixel value from a sampling area having an autocorrelation score indicating that a decodable indicia is present.

9. The indicia reader of claim 8, wherein the processor averages the pixel value for the selected sampling path with a decodable indicia segment of the paths for calculation of white level.

10. The indicia reader of claim 8, wherein the white level is calculated on the basis of selective sampling paths chosen according to an autocorrelation score.

11. The indicia reader of claim 1, wherein the processor is configured for:

running a multitasking operating system;

processing the certain frame to evaluate its frame quality according to a first program thread; and

attempting to decode the previous frame according to a second program thread.

12. The indicia reader of claim 1, wherein the result of frame quality evaluation for a certain frame is reported in a reference data location for the certain frame.

13. The indicia reader of claim 1, comprising memory, wherein the processor is configured for:

storing the captured succession of frames in memory;

at a first time, commencing attempting to decode the previous frame;

at a second time, determining whether the previous frame can be decoded;

if the previous frame cannot be decoded, selecting a next frame that was stored in memory at a time between the first time and the second time; and

attempting to decode the next frame.

14. The indicia reader of claim 1, wherein the processor is restricted from ceasing the decode processing for a certain frame if a decode status indicates that decoding is nearly complete according to a predetermined criteria.

15. The indicia reader of claim 1, wherein the processor is configured for:

in response to a successful attempt to decode the previous frame, storing a first code word from the decoded previous frame;

decoding the certain frame to obtain a second code word; and

combining the first code word and the second code word.

16. An indicia reader comprising:

an image sensor;

a processor in communication with the image sensor, the processor being configured for;

capturing a succession of frames of image data with the image sensor;

evaluating frame quality of a certain frame of the succession of frames based on a frame quality parameter;

determining if the evaluated frame quality of the certain frame satisfies a predetermined criteria;

while evaluating frame quality of the certain frame and/or determining if the evaluated frame quality of the certain frame satisfies a predetermined criteria, attempting to decode a previous frame within the succession of frames captured prior to the certain frame; and

if the certain frame satisfies the predetermined criteria, ceasing the attempt to decode the previous frame.

17. The indicia reader of claim 16, wherein the succession of frames of image data comprises one of full frames, windowed frames, and a combination of full and windowed frames.

18. The indicia reader of claim 16, comprising memory, wherein the processor is configured for:

storing the succession of frames of image data and a result of quality evaluation of the succession of frames in the memory;

if an attempt to decode fails, selecting a frame from the stored succession of frames of image data having a highest quality result; and

attempting to decode the selected frame.

19. An indicia reader comprising:

an image sensor;

memory;

a processor communicatively coupled to the image sensor and memory, wherein the processor is configured for;

capturing a succession of frames of image data with the image sensor;

processing a certain frame of the succession of frames to evaluate its frame quality based on at least one frame quality parameter;

determining whether the evaluated frame quality satisfies a first predetermined criteria;

while processing the certain frame, attempting to decode a previous frame within the succession of frames captured prior to the certain frame;

if the certain frame satisfies the first predetermined criteria, ceasing the attempt to decode the previous frame;

storing the succession of frames of image data and a result of quality evaluation of the succession of frames in the memory;

if an attempt to decode fails, selecting a frame from the stored succession of frames of image data having a highest quality result; and

attempting to decode the selected frame.

20. The indicia reader of claim 19, wherein the succession of frames of image data comprises one of full frames, windowed frames, and a combination of full and windowed frames.