public static PreparedLearningDataset ParseFromGZipedDefinitionsForCntk(ITrainingDatasetDefinition datasetDefinition)
{
var output = new PreparedLearningDataset();
output.ValueToLabelMap = BuildEMNISTValueToLabelMapFor(datasetDefinition);
output.TrainingDatasetPath = ReadEMNISTInCntkFormat(datasetDefinition, output.ValueToLabelMap, true);
output.TestingDatasetPath = ReadEMNISTInCntkFormat(datasetDefinition, output.ValueToLabelMap, false);
return(output);
}
private static char CntkLabelFromLabelStream(int[] labelStream, PreparedLearningDataset preparedDataset)
{
byte counter = preparedDataset.ValueToLabelMap.Keys.OrderBy(k => k).FirstOrDefault();
foreach (var item in labelStream)
{
if (item == 1)
{
return(preparedDataset.ValueToLabelMap[counter]);
}
counter++;
}
throw new InvalidOperationException();
}
private CntkDatasetRow ParseLineAsCntkDatasetRow(string readLine,
ITrainingDatasetDefinition datasetDefinition, PreparedLearningDataset dataset)
{
var rowStreams = readLine.Split('|').Skip(1).ToList();
var labelStream = GetDatasetStreamItems(rowStreams[0], "labels");
return(new CntkDatasetRow
{
DatasetName = datasetDefinition.DataSetName,
ImagePixels = GetDatasetStreamItems(rowStreams[1], "features"),
Label = CntkLabelFromLabelStream(labelStream, dataset)
});
}
