how to plot multiple images (separately) in one window

Question

Fatma Nur Disci 2020-12-29

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/704362-how-to-plot-multiple-images-separately-in-one-window

评论： Adam Danz 2020-12-30

Hi everyone,

I have 2304x1024 matrix. I assume that each 3 rows of this matrix describe an image.(so I have 768 images and each image size = 3x1024 ).

Let's assume that imagesc(1:3, 1024 ) gives the first image, imagesc(4:6,1024) describes the second one and so on.

My code is here :

for ind=1:768
    start= (ind-1)*3+1;
    stop=ind*3;
    data = wholedata(start:stop,:);
   imagesc(data);     %%%%   or pcolor(data) or  %%%% I = mat2gray(data) and imshow(I)
end

When I use plot instead of imagesc I can plot multiple graphs in one figure :

figure
for ind=1:768
    start= (ind-1)*3+1;
    stop=ind*3;
    data = wholedata(start:stop,:);
   subplot(1,768,ind);
   plot(data);    
   hold on; 
end

I want to display images not graphs.

How to plot multiple images side by side in 1x768 format in a figure for example ? Or 32x24 format in a figure?

Thanks for your help.

2 个评论
显示无隐藏无

Image Analyst 2020-12-30

编辑：Image Analyst 2020-12-30

在 MATLAB Online 中打开

You aren't really going to display 768 images side by side across your display are you? Each image or plot would be only a pixel or two wide! Even if you did

subplot(28, 28, ind);

they'd still be pretty tiny!

If your screen is in a 9x16 aspect ratio, you can say (9*r) * (16*r) = 768, or r=2.3 and your subplot would look like

subplot(21, 37, ind);

Adam Danz 2020-12-30

...or use tiledlayout('flow') and let Matlab arrange the plots for you. But even that has problems as I illustrated in my answer.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

KALYAN ACHARJYA 2020-12-29

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/704362-how-to-plot-multiple-images-separately-in-one-window#answer_586252

编辑：KALYAN ACHARJYA 2020-12-29

在 MATLAB Online 中打开

"How to plot multiple images side by side in 1x768 format in a figure for example?"

I assumed that you want to divide the data into several subsections. Plots display data in the same axes, while imageshows or images can display with a concatenation (horizontal or vertical). Although you can arrange 2D individual planes in a 3D vector.

If plots multiple subdivisions from image or matrix data, in this case you can follow-

1st way: If you are looking for plot sections of the data matrix differently, you have follow the following ways, please set the subplot subwindows number accordingly

data=randi([0,255],[2304,1024]);
data_blocks=mat2cell(data,3*ones(1,768),1024);
for i=1:length(data_blocks)
  subplot(6,128,i), imagesc(data_blocks{i})
end 

2nd way: Directly access the indices using loop

data=randi([0,255],[2304,1024]);
for i=1:3:2304
  subplot(....),imagesc(data(i:i+2,:))
end 

Note: Please note on the large numbers of figures/plots

3 个评论
显示 1更早的评论隐藏 1更早的评论

KALYAN ACHARJYA 2020-12-29

"I have 2304x1024 matrix. I assume that each 3 rows of this matrix describe an image.(so I have 768 images and each image size = 3x1024 )."

You can set the tile layout (subplot) as per total window display, please do the changes as per requirements

6x128=768, see the subplot function

If you are using MATLAB version 2019b or latest, you can use title function

https://www.mathworks.com/help/matlab/ref/tiledlayout.html

Fatma Nur Disci 2020-12-30

Thanks ! Yesterday I plotted all images just adding my code "subplot" before imagesc :

for ind=1:768

start= (ind-1)*3+1;

stop=ind*3;

data = wholedata(start:stop,:);

subplot(32,24,ind)

imagesc(data); %%%% or pcolor(data) or %%%% I = mat2gray(data) and imshow(I)

end

请先登录，再进行评论。

Answer 2

Adam Danz 2020-12-29

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/704362-how-to-plot-multiple-images-separately-in-one-window#answer_586883

在 MATLAB Online 中打开

768 independent axes on a figure will likely be problematicm, specifically the memory needed and the tiny size of each axis.

To demonstrate, the code below creates all 768 axes but I had to stop it after 551 axes because it was taking too long to add another axes (scroll down for more advice).

wholedata = rand(2304,1024); 
nImages = size(wholedata,1)/3; 
assert(mod(nImages,1)==0, 'The number of rows of data does not agree with number of images.')
data3D = reshape(wholedata',size(wholedata,2),3,[]); 
fig = figure();
tlo = tiledlayout(fig,'flow','TileSpacing','compact','Padding','compact');
for i = 1:size(data3D,3)
    ax = nexttile(tlo);
    imagesc(ax,data3D(:,:,i)')
end