Blurred image detection for text recognition

• US 8,665,338 B2
• Filed: 03/03/2011
• Issued: 03/04/2014
• Est. Priority Date: 03/03/2011
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Koo, Hyung-Il, Kim, Taesu, Kim, Ki-Hyun, Lee, Te-Won
• Primary Examiner(s): AGGARWAL, YOGESH K
• Application Number:
  US13/039,875
• Publication Number:
  US 20120224072A1
• Time in Patent Office: 1,097 Days
• Field of Search: 348/208.1, 348/208.2, 348/208.4, 348/208.7, 348/208.99
• US Class Current: 348/208.1
• CPC Class Codes: G06V 20/62 Text, e.g. of license plates, overlay texts or captions on TV images
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/142 using hand-held instruments; Constructional details of the instruments
• CPC Class Codes: H04N 23/683 performed by a processor, e.g. controlling the readout of an image memory
• CPC Class Codes: H04N 23/684 performed by controlling the image sensor readout, e.g. by controlling the integration time

Abstract

Techniques are described for identifying blurred images and recognizing text. One or more images of text may be captured. A change of movement associated with each image of the one or more images may be calculated. The change of movement associated with an image of the one or more images represents a change in an amount of acceleration of the device used to capture the image while the image was being captured. A steady image may be selected from the one or more images to use for text recognition. The steady image can be selected using the variances of acceleration associated with each image of the one or more images.

Claims

1. A system for recognizing text, the system comprising:

an image capture device configured to capture a plurality of images that each comprise text;

a movement measurement device configured to measure acceleration of the image capture device; and

a processor configured to;

determine, using the movement measurement device, a change of acceleration value associated with each image of the plurality of images, wherein;

each change of acceleration value represents a change in an amount of acceleration of the image capture device while a corresponding image of the plurality of images was being captured;

cause capturing of the plurality of images and determining of change of acceleration values associated with the plurality of images to occur until an image associated with a change of acceleration value below a predefined threshold change of acceleration value is determined; and

select the image to use for text recognition.

2. The system of claim 1, wherein the processor is further configured to perform text recognition on at least some of the text of the image.

3. The system of claim 1, wherein the processor is further configured to determine whether the image is desirable to use for text recognition.

4. The system of claim 1, wherein the processor, the image capture device, and the movement measurement device are part of a cellular phone.

5. The system of claim 1, wherein the image capture device is selected from a group consisting of:

a still camera; and

a video camera.

6. The system of claim 1, wherein the movement measurement device is selected from a group consisting of:

an accelerometer; and

a gyroscope.

7. The system of claim 1, wherein:

the movement measurement device is an acceleration measurement device; and

the change of movement values associated with each of the one or more images are variances of acceleration values.

8. A method for capturing sharper images, the method comprising:

capturing, by a computerized device, a plurality of images;

determining, by the computerized device, a change of acceleration value of the computerized device associated with each image of the plurality of images, wherein;

each change of acceleration value represents a change in an amount of acceleration of the computerized device while a corresponding one of the plurality of images was being captured;

capturing of the plurality of images and determining of change of acceleration values associated with the plurality of images occurs until an image associated with a change of acceleration value below a predefined threshold change of acceleration value is determined; and

selecting, by the computerized device, the image to use for text recognition.

9. The method of claim 8, further comprising determining whether the image is desirable to use for text recognition, wherein the one or more images comprises text.

10. The method of claim 8, wherein the computerized device comprises an accelerometer.

11. The method of claim 8, wherein the computerized device is a cellular phone.

12. The method of claim 8, wherein the computerized device comprises an image capture device used to capture the plurality of images, the image capture device selected from a group consisting of:

a still camera; and

a video camera.

13. An apparatus for capturing a steady image, the apparatus comprising:

means for capturing a plurality of images;

means for detecting movement of the means for capturing the plurality of images;

means for determining a change of movement value associated with each image of the plurality of images, wherein;

each change of acceleration value represents a change in an amount of acceleration of the means for capturing the plurality of images while a corresponding one of the plurality of images was being captured;

means for causing capture of the plurality of images and determination of change of acceleration values associated with the plurality of images to occur until an image associated with a change of acceleration value below a predefined threshold change of acceleration value is determined; and

means for selecting the image to use for text recognition.

14. The apparatus of claim 13, further comprising means for performing text recognition on text of the image.

15. The apparatus of claim 13, wherein:

while the image capture device is capturing each image of the one or more images, a person is holding the means for capturing the one or more images and the person is attempting to hold the means for capturing the one or more images stationary.

16. A computer program product residing on a non-transitory processor-readable medium and comprising processor-readable instructions configured to cause a processor to:

induce a plurality of images to be captured;

determine a change of acceleration value associated with each image of the plurality images, wherein;

each change of acceleration value represents a change in an amount of acceleration of an image capture device while a corresponding one of the plurality images was being captured by the image capture device;

cause capturing of the plurality of images and determining of change of acceleration values associated with the plurality of images to occur until an image associated with a change of acceleration value below a predefined threshold change of acceleration value is determined; and

select the image.

17. The computer program product of claim 16, further comprising processor-readable instructions configured to cause the processor to perform text recognition on text of the image.

18. The computer program product of claim 16, further comprising processor-readable instructions configured to use acceleration measurements to determine each change of acceleration value associated with each image of the one or more images.