IP Library Granted Patent US 8,249,309
Granted Patent B2
US 8,249,309 · App. 11/096,703 · Granted Aug 21, 2012

Image evaluation for reading mode in a reading machine

Assignee: K-NFB Reading Technology, Inc.
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Quick Facts
Patent No.
US 8,249,309
App. No.
11/096,703
Granted
Aug 21, 2012
Kind
B2
Abstract

A portable reading machine detects poor image conditions for performing optical character recognition processing. The portable reading machine receives an image of sufficient resolution to distinguish lines of text but not necessarily of sufficient resolution to distinguish individual characters and processes the image to determine imaging conditions from the image. The reading machine reports imaging conditions to the user.

Claims (67)

1. A computer program product embodied on a computer readable medium for causing a computing device of a portable reading machine for visually disabled persons to detect poor imaging conditions comprising instructions for causing the computing device to:

receive an image of sufficient resolution to distinguish lines of text but not necessarily of sufficient resolution to distinguish individual characters;

process the image to determine imaging light conditions under which the image was taken, by instructions to:

examine contrast characteristics of different parts of the image by examining a distribution of light intensities across the image, with regions of the image that have poor contrast characterized by a relatively narrow distribution of light intensity values compared to regions of good contrast;

determine whether poor contrast is present due to lighting that is too dim or too bright; and

determine whether glare conditions saturate the image and blur or obscure text that may be present in the image;

generate directions to convey to an operator of the portable reading machine based on processing the image; and

apply the generated directions to a text to speech synthesis module to provide an audio report of determined imaging lighting conditions as one of the imaging conditions and generated directions to the operator.

2. The computer program product of claim 1 wherein instructions to process the image to determine imaging conditions comprise instructions to cause the computing device to:

determine quality of at least one condition that is related to positioning of the reading machine that the computing device is operating in.

3. The computer program product of claim 1 wherein instructions to determine the quality of the lighting conditions, comprise instructions to:

compute the distribution of light intensities across the image.

4. The computer program product of claim 1 wherein the instructions to generate directions to the operator comprise instructions to cause the computing device to:

determine lighting conditions that the computing device is operating in and

report that an image input device may be out of focus if the determination of lighting quality has determined that there is low contrast in a region of the image.

5. The computer program product of claim 1 wherein the computer program product causes the device to determine if a plurality of characters are on the right side or the left side of the image, and if on the left side, to report that the text may be upside-down.

6. The computer program product of claim 1 wherein instructions to process the image to determine imaging conditions comprise instructions to:

determine that the text is too small; and the instructions to report,

report text as too small as one of the imaging conditions.

7. The computer program product of claim 1 wherein instructions to process the image to determine imaging conditions comprise instructions to:

determine that the text is too large; and the instructions to report,

report the text as too large as one of the imaging conditions.

8. The computer program product of claim 1 wherein instructions to process the image to determine imaging conditions comprise instructions to cause the computing device to:

detect that an image input device or an object whose image was captured by the image input device was tilted and that as a result text in the image is rotated or distorted; and the instructions to report, report tilt as one of the imaging conditions.

9. The computer program product of claim 1 wherein instructions to process the image to determine imaging conditions comprise instructions to cause the computing device to:

detect that text is incomplete; and the instructions to report, report that text is incomplete as one of the imaging conditions.

10. A machine comprises:

a processing device;

a computer program product residing on a computer readable medium for causing the processing device to detect poor reading conditions for the reading machine, comprising instructions for causing the machine to:

receive an image of a scene;

process the image to determine imaging lighting conditions under which the image was taken, by instructions to:

examine contrast characteristics of different parts of the image by examining a distribution of light intensities across the image, with regions of the image that have poor contrast characterized by a relatively narrow distribution of light intensity values compared to regions of good contrast;

determine whether poor contrast is present due to lighting that is too dim or too bright; and

determine whether glare conditions saturate the image and blur or obscure text that may be present in the image; and

report the determined imaging lighting conditions.

11. The machine of claim 10 wherein the computing program product further comprises instructions to:

examine contrast characteristics of different parts of the image;

determine the brightness in different regions of the image; and

compute a distribution of light intensities across the image.

12. The machine of claim 10 wherein the computing program product further comprises instructions to:

detect and report incomplete or unreadable text.

13. The machine of claim 10 wherein the computing program product further comprises instructions to:

detect that an image input device or an object whose image was captured by the image input device was tilted and that as a result text in the captured image is rotated or distorted.

14. A method of operating a machine, the method comprises:

receiving an image of sufficient resolution to distinguish lines of text but not necessarily of sufficient resolution to distinguish individual characters;

processing the image by a computing device provided in the machine to determine imaging lighting conditions under which the image was taken, by:

examining by the computing device contrast characteristics of different parts of the image by determining a distribution of light intensities across the image, with regions of the image that have poor contrast characterized by a relatively narrow distribution of light intensity values compared to regions of good contrast;

determining by the computing device whether poor contrast is present due to lighting that is too dim or too bright; and

determining by the computing device whether glare conditions saturate the image and blur or obscure text that may be present in the image; and

producing a speech file by the computing device, to convey the determined imaging conditions audibly to a user.

15. The method of claim 14 further comprising:

examining contrast characteristics of different parts of the image;

determining the brightness in different regions of the image; and

computing a distribution of light intensities across the image.

16. The method of claim 14 further comprising:

detecting and reporting incomplete or unreadable text.

17. The method of claim 14 further comprising:

detecting that an image input device or an object whose image was captured by the image input device was tilted and that as a result text in the captured image is rotated or distorted.

18. The computer program product of claim 1 wherein the computing program further comprises instructions to:

generate directions to convey to an operator of the machine a change in placement of the machine relative to a scene of which the image was taken, based on processing the image to determine imaging conditions; and

apply text to speech synthesis to the generated directions to provide an audio file that when rendered to the operator reports the generated directions to change placement.

19. The machine of claim 14 wherein the computing program further comprises instructions to:

generate directions to convey to an operator of the machine a change in placement of the machine relative to a scene of which the image was taken, based on processing the image to determine imaging conditions; and

apply text to speech synthesis to the generated directions to provide an audio file that when rendered to the operator reports the generated directions to change placement.

20. The method of claim 14 further comprising:

generating directions to convey to an operator of the machine changes in placement of the machine relative to a scene of which the image was taken, based on processing the image to determine light conditions; and

generating speech by applying by the computing device the generated directions to text to speech processing to produce an audio file that when rendered to the operator reports the generated directions to change placement.

Assignments (11)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 6, 2022
From: KNFB READER, LLC
To: THE NATIONAL FEDERATION OF THE BLIND
Reel/Frame 058577/0914 →
RELEASE AND TERMINATION OF LIENS Recorded Jan 27, 2016
From: FISH & RICHARDSON P.C.
To: KNFB READER, LLC
Reel/Frame 037603/0342 →
LICENSE Recorded May 1, 2015
From: KNFB READER, LLC
To: DIMENSIONAL STACK ASSETS LLC
Reel/Frame 035546/0143 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 29, 2015
From: K-NFB READING TECHNOLOGY, INC.
To: KNFB READER, LLC
Reel/Frame 035522/0289 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 21, 2013
From: K-NFB HOLDING TECHNOLOGY, INC.
To: K-NFB READING TECHNOLOGY, INC.
Reel/Frame 030059/0351 →
CHANGE OF NAME Recorded Mar 21, 2013
From: K-NFB READING TECHNOLOGY, INC.
To: K-NFB HOLDING TECHNOLOGY, INC.
Reel/Frame 030058/0669 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 8, 2006
From: KURZWEIL, RAYMOND C.; ALBRECHT, PAUL; GIBSON, LUCY; LVOVSKY, LEV
To: KURZWEIL TECHNOLOGIES, INC.
Reel/Frame 017319/0078 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 8, 2006
From: KURZWEIL TECHNOLOGIES, INC.
To: K-NFB READING TECHNOLOGY, INC.
Reel/Frame 017319/0439 →
CORRECTIVE ASSIGNMENT TO CORRECT THE ASSIGNEE'S NAME PREVIOUSLY RECORDED ON REEL 016865 FRAME 0003. ASSIGNOR(S) HEREBY CONFIRMS THE NAME OF THE ASSIGNEE IS NATIONAL FEDERATION OF THE BLIND. Recorded Dec 8, 2005
From: GASHEL, JAMES
To: NATIONAL FEDERATION OF THE BLIND
Reel/Frame 016869/0310 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 7, 2005
From: NATIONAL FEDERATION OF THE BLIND
To: K-NFB READING TECHNOLOGY, INC.
Reel/Frame 016864/0996 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 7, 2005
From: GASHEL, JAMES
To: NATIONAL FEDERATION FOR THE BLIND
Reel/Frame 016865/0003 →
Continuity (2)
Provisional Application 60559091 · Apr 2, 2004
Related Publication 20060008122A1 · Jan 12, 2006