DataStore, change labels in R2020a

Hello,

Is there a way to change all labels in an imageDataStore to an appended version of the current label?

I have my images saved in folders with the folder name being the label. Once I load these into an ImageDataStore, I would like to split them into two smaller datastores and then I would like to change each label to be "current label" + "_A".

In psudo code:

For every label in data store 1, rename to be label + "_A".

For every label in data store 2, rename to be label + "_B".

Is this possible?

Thank you!

Answer 1

[yanqi liu]

yes，sir，may be use subset and string contract to generate，such as

 imds = imageDatastore(fullfile(matlabroot,'toolbox','matlab'),...
'IncludeSubfolders',true,'FileExtensions','.tif','LabelSource','foldernames')

imds = 
  ImageDatastore with properties:

                       Files: {
                              '/MATLAB/toolbox/matlab/demos/example.tif';
                              '/MATLAB/toolbox/matlab/imagesci/corn.tif'
                              }
                     Folders: {
                              '/MATLAB/toolbox/matlab'
                              }
                      Labels: [demos; imagesci]
    AlternateFileSystemRoots: {}
                    ReadSize: 1
      SupportedOutputFormats: ["png"    "jpg"    "jpeg"    "tif"    "tiff"]
         DefaultOutputFormat: "png"
                     ReadFcn: @readDatastoreImage

 
 imds.Labels=categorical(erase(string(imds.Labels), ' ') + repmat('_A', size(imds.Labels, 1), 1))

imds = 
  ImageDatastore with properties:

                       Files: {
                              '/MATLAB/toolbox/matlab/demos/example.tif';
                              '/MATLAB/toolbox/matlab/imagesci/corn.tif'
                              }
                     Folders: {
                              '/MATLAB/toolbox/matlab'
                              }
                      Labels: [demos_A; imagesci_A]
    AlternateFileSystemRoots: {}
                    ReadSize: 1
      SupportedOutputFormats: ["png"    "jpg"    "jpeg"    "tif"    "tiff"]
         DefaultOutputFormat: "png"
                     ReadFcn: @readDatastoreImage

[Paween Pongsomboon]

@yanqi liu You save my life. Thank you. I'm gonna cry I have been struggled with this problem for three days and now you don't know how much I wanna hug you.

[Yongwon Jang]

Thank you. It was very helpful.

For my case, erased total labels and reassigned new labels.

I utilized it and edited for my purpose.

Indeed, You are angel.