How to display second level dwt?

Hi. I want to display second level dwt. If I display seperatly to frequency components, it works fine. But when I try to merge and display, It appears just black color. Here is my code

close all;

clear;

cd 'C:\Users\LENOVO\OneDrive\Masaüstü' %% Uploading picture to Matlab

X=imread('Coleen.jpg','jpg');%Reading picture by Matlab

[LoD,HiD] = wfilters('haar','d');

[cA,cH,cV,cD] = dwt2(X,LoD,HiD,'mode','symh');

[cA2,cH2,cV2,cD2]=dwt2(cA,LoD,HiD,'mode','symh');

subplot(2,2,1)

imagesc(cA)

colormap gray

title('Approximation')

subplot(2,2,2)

imagesc(cH)

colormap gray

title('Horizontal')

subplot(2,2,3)

imagesc(cV)

colormap gray

title('Vertical')

subplot(2,2,4)

imagesc(cD)

colormap gray

title('Diagonal')

figure

Level2=[cA2,cH2; cV2,cD2];

imagesc([Level2,cH; cV,cD]);

colormap gray

It appears like this. But I want to display it like below.

Please. Could you help me?

Answer 1

[yanqi liu]

yes，sir，may be use the dimension information，such as

close all;
clear all;  clc;
%Reading picture by Matlab
X=imread('cameraman.tif');
[LoD,HiD] = wfilters('haar','d');
[cA,cH,cV,cD] = dwt2(X,LoD,HiD,'mode','symh');
[cA2,cH2,cV2,cD2]=dwt2(cA,LoD,HiD,'mode','symh');
figure
Level2=[mat2gray(cA2),mat2gray(cH2); mat2gray(cV2),mat2gray(cD2)];
d = [Level2,mat2gray(cH); mat2gray(cV),mat2gray(cD)];

% get dimension
rects1 = [1 1 size(cA2)
    1 2 size(cA2)
    2 1 size(cV2)
    2 2 size(cD2)];
rects2 = [1 1 size(Level2)
    1 2 size(cH)
    2 1 size(cV)
    2 2 size(cD)];
rects = {rects1, rects2};

imagesc(d);
colormap gray
axis equal
axis off

hold on; 
rectangle('position', [1 1 size(d,2)-1 size(d,1)-1], 'EdgeColor', 'y', 'LineWidth', 2)
for k = 1 : length(rects)
    rectsk = rects{k};
    for i = 1 : size(rectsk, 1)
        recti = [zeros(1, 2) rectsk(i,3:4)];
        % get location
        rowi = rectsk(i,1);
        coli = rectsk(i,2);
        for j = 1 : coli-1
            recti(1) = recti(1) + rectsk(j, 4);
        end
        for j = 1 : rowi-1
            recti(2) = recti(2) + rectsk(j, 3);
        end
        rectangle('position', recti, 'EdgeColor', 'y', 'LineWidth', 2)
    end
end

[Imtiyaz Ahmad]

Hi,

I am facing an issue while using Daubechies wavelet , its says an error as ;Error using horzcat

Dimensions of arrays being concatenated are not consistent.... but its working fine while using haar wavelet, can you provide the solution for that also ..