OCR function does not recognize number 8

Hello,

I do have a Problem with the ocr Function of Matlab.

It does a very poor job, particulary in recognizing the number 8.

This the i am giving into the ocr function, however, the ocr funktion does return 6 or 9 or 5 more often, than it recognizes an 8.

I added some pictures in the attached zip archive if somebody wants to have a go.

This is the code i am using:

image=rgb2gray(img_rgb(leftedge:rigthedge,upperedge:loweredge);
OcrObjekt=ocr(image,'CaracterSet','0123456789.','Textlayout','Word');
result=strtrim(OcrObjekt.Words{1});

Thank you for your answers!

[KALYAN ACHARJYA]

May work?

Do some sort of preprocessing on images before applying the OCR.

[Niklas Arold]

I did try a lot of different techniques for preprocessing, but none of them gave acceptable results.

Answer 1

[Devineni Aslesha]

While passing the image data to ocr function, no need to convert the image from RGB to gray as ocr function converts truecolor or grayscale input images to a binary image, before the recognition process using Otsu’s thresholding technique.

Use the below code for reference.

I = imread('Image8.png'); 
txt = ocr(I,'CharacterSet','0123456789.','Textlayout','Word'); 
txt.Text 

Here, Image8 is the image provided in the question. It is showing the correct result.

Doc Link:

https://www.mathworks.com/help/vision/ref/ocr.html