IP Library Granted Patent US 9,959,475
Granted Patent B2
US 9,959,475 · App. 15/195,361 · Granted May 1, 2018

Table data recovering in case of image distortion

Inventors: Maksim Petrovich Kalenkov (Tatarstan, RU); Dmitrij Yurievich Chubanov (Moscow oblast, RU)
Assignee: ABBYY DEVELOPMENT LLC
G06K9/18G06F17/212G06K9/00449G06T7/0085
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 9,959,475
App. No.
15/195,361
Granted
May 1, 2018
Kind
B2
Abstract

The subject matter of this specification can be implemented in, among other things, a method that includes identifying edges of a section of a document in a source image that includes at least one row of text. The method includes identifying characters in the document. The method includes identifying word portions. The method includes generating polynomials that approximate points of the characters within the word portions. The method includes generating a second polynomial that approximates the points of the characters of word portions. The method includes identifying a stretching coefficient of the row of text based on a length of the section between the edges relative to a length of the second polynomial. The method includes mapping portions of the source image along the row of text to new positions in a corrected image based on the second polynomial and the stretching coefficient.

Claims (47)

1. A method comprising:

identifying edges of at least a section of a document in a source image, wherein the document comprises at least one first row of text;

identifying a plurality of characters in the document;

identifying ones of the characters as a plurality of word portions;

generating a plurality of first polynomials that approximate points of the characters within the word portions;

generating a second polynomial that approximates the points of the characters of at least a first word portion and a second word portion among the word portions and corresponds to the first row of text;

identifying at least one stretching coefficient of the first row of text based on a maximum length of the section between the edges and a length of the second polynomial; and

mapping, by at least one processing device, portions of the source image along the first row of text to new positions in a corrected image based on the second polynomial and the stretching coefficient.

2. The method of claim 1 , wherein the points of the characters are along a plurality of baselines of the word portions.

3. The method of claim 1 , wherein the second polynomial defines one or more second angles representing slopes along the second polynomial, wherein the method further comprises stepping through existing positions in the source image by a step size that is smaller than a pixel size of the source image, and wherein mapping the portions comprises mapping each of the existing positions to the new positions based on the second angles, the stretching coefficient, and the step size.

4. The method of claim 1 , wherein the first polynomials define a plurality of first angles representing slopes along the first polynomials, wherein the second polynomial defines a plurality of second angles representing slopes along the second polynomial, and wherein the method further comprises verifying that ones of the first angles for the first word portion and the second word portion are within a threshold level of accuracy from corresponding ones of the second angles.

5. The method of claim 1 , further comprising verifying that the first word portion and the second word portion are at least a threshold distance away from at least one second row of text in the document next to the first row of text, wherein the threshold distance is based on an average distance between polynomials corresponding to rows of text in the document.

6. The method of claim 1 , further comprising verifying that the second polynomial is within a threshold level of similarity to at least one third polynomial corresponding to at least one second row of text in the document.

7. The method of claim 1 , further comprising interpolating a color for each new position in the new positions of the corrected image based on colors from pixels of the source image in a vicinity of a portion among the portions of the source image that corresponds to the new position.

8. The method of claim 1 , further comprising pre-processing the source image, wherein pre-processing comprises performing one or more of applying a gamma filter to the source image, normalizing a width and a height of the source image, adjusting a brightness of the source image, or binarizing a color depth of the source image.

9. The method of claim 1 , wherein identifying the edges is based on a line detection algorithm or an edge detection algorithm.

10. The method of claim 1 , wherein the new positions of the portions remove distortion from the first row of text in the corrected image.

11. The method of claim 1 , further comprising:

generating at least one interpolated polynomial between the second polynomial and at least one third polynomial corresponding to at least one second row of text in the document; and

mapping portions of the source image between the first row of text and the second row of text to new positions in the corrected image based on the interpolated polynomial.

12. A non-transitory computer-readable medium having instructions stored thereon that, when executed by at least one processing device, cause the processing device to:

identify edges of at least a section of a document in a source image, wherein the document comprises at least one first row of text;

identify a plurality of characters in the document;

identify ones of the characters as a plurality of word portions;

generate a plurality of first polynomials that approximate points of the characters within the word portions;

generate a second polynomial that approximates the points of the characters of at least a first word portion and a second word portion among the word portions and corresponds to the first row of text;

identify at least one stretching coefficient of the first row of text based on a maximum length of the section between the edges and a length of the second polynomial; and

map, by the processing device, portions of the source image along the first row of text to new positions in a corrected image based on the second polynomial and the stretching coefficient.

13. A system comprising:

at least one memory that stores instructions; and

at least one processing device to execute the instructions to:

identify edges of at least a section of a document in a source image, wherein the document comprises at least one first row of text;

identify a plurality of characters in the document;

identify ones of the characters as a plurality of word portions;

generate a plurality of first polynomials that approximate points of the characters within the word portions;

generate a second polynomial that approximates the points of the characters of at least a first word portion and a second word portion among the word portions and corresponds to the first row of text;

identify at least one stretching coefficient of the first row of text based on a maximum length of the section between the edges and a length of the second polynomial; and

map portions of the source image along the first row of text to new positions in a corrected image based on the second polynomial and the stretching coefficient.

14. The system of claim 13 , wherein the points of the characters are along a plurality of baselines of the word portions.

15. The system of claim 13 , wherein the second polynomial defines one or more second angles representing slopes along the second polynomial, wherein the processing device is further to step through existing positions in the source image by a step size that is smaller than a pixel size of the source image, and wherein, to map the portions, the processing device is further to map each of the existing positions to the new positions based on the second angles, the stretching coefficient, and the step size.

16. The system of claim 13 , wherein the first polynomials define a plurality of first angles representing slopes along the first polynomials, wherein the second polynomial defines a plurality of second angles representing slopes along the second polynomial, and wherein the processing device is further to verify that ones of the first angles for the first word portion and the second word portion are within a threshold level of accuracy from corresponding ones of the second angles.

17. The system of claim 13 , wherein the processing device is further to verify that the first word portion and the second word portion are at least a threshold distance away from at least one second row of text in the document next to the first row of text, and wherein the threshold distance is based on an average distance between polynomials corresponding to rows of text in the document.

18. The system of claim 13 , wherein the processing device is further to verify that the second polynomial is within a threshold level of similarity to at least one third polynomial corresponding to at least one second row of text in the document.

19. The system of claim 13 , wherein the new positions of the portions remove distortion from the first row of text in the corrected image.

20. The system of claim 13 , wherein the processing device is further to:

generate at least one interpolated polynomial between the second polynomial and at least one third polynomial corresponding to at least one second row of text in the document; and

map portions of the source image between the first row of text and the second row of text to new positions in the corrected image based on the interpolated polynomial.

Assignments (3)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 25, 2022
From: ABBYY PRODUCTION LLC
To: ABBYY DEVELOPMENT INC.
Reel/Frame 059249/0873 →
MERGER Recorded Dec 31, 2018
From: ABBYY DEVELOPMENT LLC
To: ABBYY PRODUCTION LLC
Reel/Frame 047997/0652 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 7, 2016
From: KALENKOV, MAKSIM PETROVICH; CHUBANOV, DMITRIJ YURIEVICH
To: ABBYY DEVELOPMENT LLC
Reel/Frame 039101/0249 →
Priority Claims (1)
RU 2016125533 · Jun 27, 2016 · national
Continuity (1)
Related Publication 20170372156A1 · Dec 28, 2017