Claims:WE CLAIM:
1. A method of detecting text in digital engineering drawings, the method comprising:
receiving, by a text detection system (101), a digital image of an engineering drawing, wherein the digital image is converted to a binary image;
detecting, by the text detection system (101), one or more lines inclined at one or more angles, in the binary image, based on pre-defined parameters, wherein the one or more lines are removed from the binary image;
determining, by the text detection system (101), one or more image contours (203) in the binary image based on connected pixels with similar characteristics;
identifying, by the text detection system (101), one or more regions in the binary image, to be non-text regions (205) based on a height, a width, and a pixel density, of corresponding one or more image contours (203) and a predefined minimum height, minimum width, maximum height, maximum width, and a predefined pixel density, wherein the one or more non-text regions (205) are removed from the binary image;
determining, by the text detection system (101), one or more text regions (207) in the binary image based on the removal of the one or more non-text regions (205); and
processing, by the text detection system (101), the one or more text regions (207) to detect text in the binary image of the engineering drawing.

2. The method as claimed in claim 1, wherein the pre-defined parameters comprises distance resolution between two lines, angle resolution of lines passing through a point, number of votes for a line, and minimum length for the line.

3. The method as claimed in claim 1, wherein identifying the one or more regions to be non-text region (205) comprises detecting the height of the one or more image contour (203) corresponding to the one or more regions to be one of, greater than a predefined maximum height and lesser than a predefined minimum height, the width of the one or more image contours (203) to be one of greater than a predefined maximum width and lesser than a predefined minimum width and the pixel density of the one or more image contours (203) to be greater than the predefined pixel density.

4. The method as claimed in claim 1, wherein the pixel density is a ratio of the number of white pixels and product of contour width and height.

5. The method as claimed in claim 1, wherein processing the one or more text regions (207) comprises:
converting the binary image to an eroded image using erosion and dilation technique;
identifying a block of text in the eroded image based on a predefined maximum height and maximum width and a predefined minimum height and minimum width of image contours (203) in the eroded image; and
detecting the text from the block of text using optical character recognition (OCR) technique.

6. A text detection system (101) for detecting text in digital engineering drawings, comprising:
a processor (111); and
a memory (109) communicatively coupled to the processor (111), wherein the memory (109) stores processor instructions, which, on execution, causes the processor (111) to:
receive a digital image of an engineering drawing, wherein the digital image is converted to a binary image;
detect one or more lines inclined at one or more angles, in the binary image, based on pre-defined parameters, wherein the one or more lines are removed from the binary image;
determine one or more image contours (203) in the binary image based on connected pixels with similar characteristics;
identify one or more regions in the binary image, to be non-text regions (205) based on a height, a width, and a pixel density, of corresponding one or more image contours (203) and a predefined minimum height, minimum width, maximum height, maximum width, and a predefined pixel density, wherein the one or more non-text regions (205) are removed from the binary image;
determine one or more text regions (207) in the binary image based on the removal of the one or more non-text regions (205); and
process the one or more text regions (207) to detect text in the binary image of the engineering drawing.

7. The text detection system (101) as claimed in claim 1, wherein the pre-defined parameters comprises distance resolution between two lines, angle resolution of lines passing through a point, number of votes for a line, and minimum length for the line.

8. The text detection system (101) as claimed in claim 1, wherein the processor (111) identifies the one or more regions to be non-text region (205) by detecting the height of the one or more image contour (203) corresponding to the one or more regions to be one of, greater than a predefined maximum height and lesser than a predefined minimum height, the width of the one or more image contours (203) to be one of greater than a predefined maximum width and lesser than a predefined minimum width and the pixel density of the one or more image contours (203) to be greater than the predefined pixel density.

9. The text detection system (101) as claimed in claim 1, wherein the pixel density is a ratio of the number of white pixels and product of contour width and height.

10. The text detection system (101) as claimed in claim 1, wherein the processor (111) processes the one or more text regions (207) by:
converting the binary image to an eroded image using erosion and dilation technique;
identifying a block of text in the eroded image based on a predefined maximum height and maximum width, a predefined minimum height and minimum width and predefined pixel density of image contours (203) in the eroded image; and
detecting the text from the block of text using optical Character Recognition (OCR) technique.

Dated this 29th day of December, 2017

R Ramya Rao
IN/PA-1607
Of K&S Partners
Agent for the Applicant , Description:TECHNICAL FIELD
The present subject matter is related in general to the field of image processing, more particularly, but not exclusively to method and system for detecting text in digital engineering drawings.