How to do OCR for an Rotatioanl String

[PalanivelThiruvenkadam]

Problem in tarining OCR for Roational String  for eg. "HELLO WORLD"

[udka]

Problem is in training step or detection step?

-I think in training step you can use rotated rectangle and select characters.

-In detection i don't see any way other than maybe using pattern match and get the text orientation and rotate image back to that and see.

-Did you try giving rotated rectangle as ROI descriptor during detection step and check? (I'm not sure if it works).

[MangeshD]

Its not a problem unless and until you share what you are doing.

If you are manually teaching/training each character in LabVIEW then you can set the orientation for the search alphabet.

In past we had worked on rotated patterns and mirror patterns as well so I dont think this will resist you if you are using NI VISION VIs.

Please share what exactly you are doing this training.

[PalanivelThiruvenkadam]

I am trying to teach via Vision Assistant but couldnt able to get the characters  being extracted to train single character.

[udka]

Looking like a bug or i might be missing something.

-Instead of training from Vision assistant try the ocr training interface separately.

-You can select the rotated rectangle and rotate and train.

-Where as when called in Vision assistant not able to use rotated rectangle.

[PalanivelThiruvenkadam]

Thanks udka,

I used NI OCR Training Interface and i can able to rotate the rectangular tool, can able to detect character and train.

Is there a way to set the ROI dynamically/ Programmatically based on the Rotated angle as used in training portion

[udka]

As i previously stated you might use pattern matching to get the orientation of text and then give the result ROI Descriptor of OCR Read Text VI.

[MangeshD]

As I know about OCR you should have good pattern of Alphabets that you would like to teach.

Since you are teaching a rotated pattern and then struggling to set the rotated ROI programatically inspite of this you can teach a straight pattern and set the rotated angle within which you want to find the rotated alphabet.

Example:

Suppose I have an alphabet 'A'. I will teach 'A' as it is(without rotation) with a default ROI rectangle.Now during a search OCR operation I would put the same ROI rectangle by adding +/- rotation angle suppose 45 degree. This will give me a freedom of searching  a pattern 45 degree left and right rotated alphabet.

I hope this might help.

[PalanivelThiruvenkadam]

Thanks for all your replies, i will try and get back if i face issue or if my issue gets resolved