OCR not working (training successuful though)

[ziedhosni]

Hello,

I spent one week to solve this OCR problem but I ended with a failure. Please help me.

I used the vision toolkit of labview to recognize number I record with a usb webcam.

During the training, everything is fine, I even tweaked the brightness and the satuation and I used grayscale level to make the train stronger and the recognition more efficient but when I call the abc file and I select the ROI, the string comes empty from any character.

I tried also to use the vision assistant but it failed also.

I attached two versions of the VI., one with and one without the vision assistant.

Cheers,

Zied

[Hockeyjim07]

Could you provide some sample images you are working with so we can run your code with what you are trying to use?

[ziedhosni]

Here some pictures.

[MoviJOHN]

With this type of display, its a bit difficult to get an OCR read, due to the separation that occurs when the center segment of the character is missing.  Try instead to use the GetPixelValue vi to read the image for the presence or absence of black in each of the seven regions of a numeral.  For each number position, you will need seven GetPixelValue calls

Example

 1

2 3

 4

5 6

 7

_

||

-

||

_

The numerals would have the folowing "bits" turned on, for which you could have a lookup table.

1 - 3, 6 -> 36

2 - 1,3,4,5,7 -> 93

3 - 1,3,4,6,7 -> 109

4 - 2,3,4,6 -> and so on...

5 - 1,2,4,6,7

6 - 1,2,4,5,6,7

7 - 1,3,6

8 - 1,2,3,4,5,6,7

9 - 1,2,3,4,6

0 - 1,2,3,5,6,7

[BruceAmmons]

Or just use the 7 segment reader that is part of the Vision toolkit.  No reason to reinvent the wheel.  It might take a little bit of work to set it up, but it works well once it is done.

Bruce

[ziedhosni]

I would like to refer to my new topic as I tried to use the LCD reader. I think it is more appropiate to what I am doing but I got another kind of problem as it is hard to define or change the ROI.

Any help!

http://forums.ni.com/t5/Machine-Vision/invalid-LCD-ROI/m-p/3086771

Thanks