How to join or merge two Image Data Stores?

If I have two image datastores and I wish to concatenate them. How can I do that?

Thanks

[Sherin Aly]

It was a bit tricky but I was able to merge 2 datastores as follows:

imds1 = imageDatastore(location of DS 1,'IncludeSubfolders',true,'LabelSource','foldernames');

imds2 = imageDatastore(imds2 location,'IncludeSubfolders',true,'LabelSource','foldernames');

% create a dummy dataset with the same size of the combined datastores (if ds1 has 100 images and ds2 has 100 images then dummy has 200 images. I made a folder with some photos with equal number of the 2 datastores)

dummy = imageDatastore('Dummy data store locaation','IncludeSubfolders',true,'LabelSource','foldernames');

% note: below this line you can use any datastore variable you want to merge including the ones you get after splitting training and testing

dummy.Files=[imds1.Files;imds2.Files];

dummy.Labels=[imds1.Labels;imds2.Labels];

% Now dummy is the new combined datastore and you can use all datastore functions

Answer 1

[Zhiqiang Qiu]

I know it is an ancient problem, but I just to make it a better reference for other people.

imds1 = imageDatastore('imds1 location', ...);
imds2 = imageDatastore('imds2 location', ...);
imds_combine = imageDatastore({'imds1 location', 'imds2 location'}, ...);

Just combine the address of these two locations. The following parameters are all the same.

[habtamu miheretie]

that is cool answer! i have very similar problem. when i create the data store the files are not in the same order as in the folder. how can i make that possible? i need it because the label i use is coming from another .csv file. so i need to match the order to process the images easily. can anyone help me on this please?

Answer 2

[Hana]

I met the same problem and saw your post. Finally I find out a way:

imds = imageDatastore(cat(1,imds1.Files,imds2.Files))
imds.Labels = cat(1,imds1.Labels,imds2.Labels)

It works for me.

[Yifan Dong]

Brilliant!! Thanks!

[Heng Zhang]

OMG! Thanks bro! That really helps!

[Yingying Pang]

brilliant!!!!!

[Silvia Guatelli]

Excelente!!! Muchas gracias!

[Joseph Garrett]

perfect. thank you so much!!

Answer 3

[berkan]

allImages.Files=[test1.Files;test2.Files]; allImages.Labels=[test1.Labels;test2.Labels];

[Sascha D. Krauß]

Unfortunately, this produces a struct instead of a new datastore - and I could not find a way to convert it back. This means, that you cannot use the datastore specific functions like "countEachLabel" etc. Does anyone know another solution?

Answer 4

[Birju Patel]

The best way to do this is to use the datastore combine method:

https://www.mathworks.com/help/matlab/ref/matlab.io.datastore.combine.html

ds = combine(imds1, imds2, ReadOrder="sequential")

The resulting datastore is a "vertical concatenation" of the two datastores.

Answer 5

[KSSV]

A = imread('ngc6543a.jpg');
B = imread('peppers.png');
%%resize the images so that they have same dimensions 
A_resize = imresize(A,[size(B,1) size(B,2)]) ;
%%join them
AB = [A_resize B] ;
imshow(AB) ;

[kowshik Thopalli]

Hi, Thanks for the answer, however I am looking to merge two

    imageDatastore

objects .

Answer 6

[Aasim Khurshid]

There is a better way to do this,

imds = imageDatastore({fullfile(imgFolder1Adress),fullfile(imgFolder2Adress),fullfile(imgFolder3Adress)},...
    'IncludeSubfolders',true,'FileExtensions','.png','LabelSource','foldernames');

Answer 7

[Matt J]

Perhaps by wrapping them in a TransformedDataStore (R2019a and higher),

imdsnew = transform(imds1,imds2, @(x) x)