Unable to perform assignment because the size of the left side is 20-by-1 and the size of the right side is 20-by-20-by-3.

Hi, I need to make image with single letter. It needs to vary in terms of font size and noise using variance(later on) under the same parameter for image size. I should store the images withdifferent font sizes of the letter and display it. Please help. I have try to store it in cell array. But it said "

How could I solve this? I tried to use cell array but I failed. Thank you. I am quite confused with the array, Hope to have someone to guide me. Thank you.

%create blank image
w = 20;
h = 20;
blankImage= 255*ones(w,h,3,'uint8');
position_x = (w+1)/2;
position_y = (h+1)/2;
% % Extract the individual red, green, and blue color channels.
% redChannel = rgbImage(:, :, 1);
% greenChannel = rgbImage(:, :, 2);
% blueChannel = rgbImage(:, :, 3);
font_size = 10;
new_font = font_size + i;
font_start = 10;
font_end = 16;
total_img = font_start:2:font_end;
length(total_img)
% size_A = zeros(8, 'int8');
%function row_column = 
% size_A = cell(1,pic_num);
% 

for i=1:length(total_img)
    for font_size = total_img(i)
        A(:,:,i)= insertText(blankImage,[position_x position_y],'A','Font','Times New Roman','FontSize',font_size,'TextColor','black','BoxColor','w','BoxOpacity',0,'AnchorPoint','Center');
        A(:,:,i)= rgb2gray(A(:,:,i));
        A(:,:,i)= imnoise(A(:,:,i), 'gaussian', 0.01);
        i = i+1;
    end
end
% subplot(2,2,1);
montage(A);
% imshow(A(i+1);
axis on;
title('A uppercase with noise');

Answer 1

[DGM]

I don't have CVT, so I can't test this, but insertText() is returning an RGB array and you're trying to fit it into a single page of a multipage image. If you're doing operations with a working image that doesn't start out with the right dimensions to fit in its destination, don't try to put it there until it does fit.

thispage = insertText(blankImage,[position_x position_y],'A','Font','Times New Roman','FontSize',font_size,'TextColor','black','BoxColor','w','BoxOpacity',0,'AnchorPoint','Center');
thispage = rgb2gray(thispage);
A(:,:,i) = imnoise(thispage, 'gaussian', 0.01);

[Tuck Wai Yip]

Oh, I understand what you mean, I ignore the for loop just now, since every loop there will only one image produced from insertText function, so I just need the

A (:,:,i) 

to store an image and the image has its own RGB channels.Please correct me if I am wrong. Thank you.

[DGM]

I don't know what you need or are trying to do. All I know is that insertText() is going to give you an RGB image, and you then are converting it to grayscale:

A(:,:,i)= rgb2gray(A(:,:,i));

That tells me that you want a single channel (grayscale) image, not an RGB image.

If you want to store the RGB arrays, you can certainly make the array 4D.

[Tuck Wai Yip]

I understand now what you trying to explain. You remind me that grayscale has changed the RGB image into 2D.Thank you for your help!

[Image Analyst]

If @DGM's answer solved your problem, please click the "Accept this answer" link to give him reputation points.

[Tuck Wai Yip]

Hi,@Image Analyst I clicked "Accept this answer" before you said it :).By the way, thank you on your reminder.