How to recognize negative numbers with OCR?
16 views (last 30 days)
Show older comments
sasad games
on 27 Feb 2021
Commented: sasad games
on 27 Feb 2021
I am using the following code to recognize numbers in images and transform it to values. However, it only recognizes positive values. Can you please help me to modify the code in order to be able to identify positive and negative values? Thanks in advance.
clc
clear all
close all
%%
I=imread('N1.png');
I2=I(:,:,3);
I3=ind2rgb(I2,gray);
I4=imcomplement(I3);
N=Im_text(I4);
function [val] = Im_text(Original)
% Increase image size by 3x
my_image = imresize(Original, 3);
% Localize words
BW = imbinarize(rgb2gray(my_image));
BW1 = imdilate(BW,strel('disk',6));
s = regionprops(BW1,'BoundingBox');
bboxes = vertcat(s(:).BoundingBox);
% Sort boxes by image height
[~,ord] = sort(bboxes(:,2));
bboxes = bboxes(ord,:);
% Pre-process image to make letters thicker
BW = imdilate(BW,strel('disk',1));
% Call OCR and pass in location of words. Also, set TextLayout to 'word'
ocrResults = ocr(BW,bboxes,'CharacterSet','.0123456789','TextLayout','word');
words = {ocrResults(:).Text}';
words = deblank(words);
val=str2double(words);
end
0 Comments
Accepted Answer
Image Analyst
on 27 Feb 2021
Edited: Image Analyst
on 27 Feb 2021
Can't you simply add a - to the CharacterSet? Then if the first character is a -, it's a negative number.
This works fine:
grayImage = imread('N1.png');
if ndims(grayImage) == 3
grayImage = rgb2gray(grayImage);
end
imshow(grayImage, 'InitialMagnification', 400);
axis('on', 'image');
N = Im_text(grayImage)
caption = sprintf('The number in here is %f', N);
title(caption, 'FontSize', 20);
%==================================================================================
function [val] = Im_text(Original)
% Increase image size by 3x
my_image = imresize(Original, 3);
ocrResults = ocr(my_image, 'CharacterSet', '-.0123456789', 'TextLayout', 'line')
words = {ocrResults(:).Text}';
words = deblank(words);
val = str2double(words);
end
More Answers (0)
See Also
Categories
Find more on Computer Vision Toolbox in Help Center and File Exchange
Products
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!