partitionCamVidData.m

function [imdsTrain, imdsVal, imdsTest, pxdsTrain, pxdsVal, pxdsTest] = partitionCamVidData(imds,pxds)
% Partition CamVid data by randomly selecting 60% of the data for training. The
% rest is used for testing.
    
% Set initial random state for example reproducibility.
rng(0); 
numFiles = numel(imds.Files);
shuffledIndices = randperm(numFiles);

% Use 60% of the images for training.
N = round(0.60 * numFiles);
trainingIdx = shuffledIndices(1:N);

M = N + round(0.20 * numFiles);
valueIdx = shuffledIndices(N+1:M);

% Use the rest for testing.
testIdx = shuffledIndices(M+1:end);

% Create image datastores for training and test.
trainingImages = imds.Files(trainingIdx);
valueImages = imds.Files(valueIdx);
testImages = imds.Files(testIdx);
imdsTrain = imageDatastore(trainingImages);
imdsVal = imageDatastore(valueImages);
imdsTest = imageDatastore(testImages);

% Extract class and label IDs info.
classes = pxds.ClassNames;
labelIDs = 1:numel(pxds.ClassNames);

% Create pixel label datastores for training and test.
trainingLabels = pxds.Files(trainingIdx);
valueLabels = pxds.Files(valueIdx);
testLabels = pxds.Files(testIdx);
pxdsTrain = pixelLabelDatastore(trainingLabels, classes, labelIDs);
pxdsVal = pixelLabelDatastore(valueLabels, classes, labelIDs);
pxdsTest = pixelLabelDatastore(testLabels, classes, labelIDs);
end