What is the best algorithm to locate a point in an image file?

Posted by suugaku on Stack Overflow See other posts from Stack Overflow or by suugaku
Published on 2010-05-24T12:13:39Z Indexed on 2010/05/24 12:21 UTC
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c#

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image

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image-processing

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gdi+

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ocr

Hi all,

I want to create a mark sheet recognizer. Here is the description:

My system uses black and white color scheme.
The mark sheet paper has a small black rectangle on each corner and an additional small black rectangle, to determine orientation, near one of the previous rectangles.
The paper is scanned to yield an image (in bmp format for example).

The first step is to locate these five references in image as eficient as possible.

My rough idea is to trace row by row and from left to right for each row. It sounds very slow I think.

Is there any better way to do that?

Thank you in advance.

regards,

Suugaku

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