detect 3 letters 'a' 'v' 'b' .

Hello everyone I need a matlab code that can detect 3 letters 'a' 'v' 'b' . from the 3 images I provided

1. Show the detected result on original image.

2. calculate the miss recognition percentages.

Anyone can help ?

[Adam Danz]

If you have the computer vision toolbox, start here

https://www.mathworks.com/help/vision/ug/recognize-text-using-optical-character-recognition-ocr.html

[Haman Fadhel]

thanks but It didn't work

I need to detect special letters not all the text

Answer 1

[yanqi liu]

yes，sir，just use simple fft process，we can make one example，use for detect a in first image.

of couse，use ocr、cnn and some classify model may get better result

such as

clc; clear all; close all;
url = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/835960/image.jpeg';
img = imread(url);
im = rgb2gray(img);
bw = imbinarize(im,'adaptive','ForegroundPolarity','dark','Sensitivity',0.4);
figure; imshow(bw);

a = ~imcrop(bw, [764 318 43 60]);
a = bwareafilt(a, 1);
bw = ~bw;
cn1 = real(ifft2(fft2(bw).*fft2(rot90(a,2), size(bw,1), size(bw,2))));
mcn1 = max(max(cn1));
cm1 = cn1 > mcn1*0.85;
[r,c] = find(cm1);
figure; imshow(img);
hold on;
for i = 1 : length(r)
    plot(c(i)-size(a,2)/2,r(i)-size(a,1)/2,'r*')
end