ML.NET 1.4.0-preview

New Features

• Deep Neural Networks Training (0.16.0-preview) (#4151)

  Improves the in-preview ImageClassification API further:

  • Increases DNN training speed by ~10x compared to the same API in 0.15.1 release.
  • Prevents repeated computations by caching featurized image values to disk from intermediate layers to train the final fully-connected layer.
  • Reduced and constant memory footprint.
  • Simplifies the API by not requiring the user to pre-process the image.
  • Introduces callback to provide metrics during training such as accuracy, cross-entropy.
  • Improved image classification sample.
  csCopy

        public static ImageClassificationEstimator ImageClassification(
            this ModelOperationsCatalog catalog,
            string featuresColumnName,
            string labelColumnName,
            string scoreColumnName = "Score",
            string predictedLabelColumnName = "PredictedLabel",
            Architecture arch = Architecture.InceptionV3,
            int epoch = 100,
            int batchSize = 10,
            float learningRate = 0.01f,
            ImageClassificationMetricsCallback metricsCallback = null,
            int statisticFrequency = 1,
            DnnFramework framework = DnnFramework.Tensorflow,
            string modelSavePath = null,
            string finalModelPrefix = "custom_retrained_model_based_on_",
            IDataView validationSet = null,
            bool testOnTrainSet = true,
            bool reuseTrainSetBottleneckCachedValues = false,
            bool reuseValidationSetBottleneckCachedValues = false,
            string trainSetBottleneckCachedValuesFilePath = "trainSetBottleneckFile.csv",
            string validationSetBottleneckCachedValuesFilePath = "validationSetBottleneckFile.csv"
            )
  
  

  Design specification

  Sample

• Database Loader (0.16.0-preview) (#4070,#4091,#4138)

  Additional DatabaseLoader support:

  • Support DBNull.
  • Add CreateDatabaseLoader<TInput> to map columns from a .NET Type.
  • Read multiple columns into a single vector

  Design specification

  Sample

  csCopy

    string connectionString = "YOUR_RELATIONAL_DATABASE_CONNECTION_STRING";
  
    string commandText = "SELECT * from URLClicks";
  
    DatabaseLoader loader = mlContext.Data.CreateDatabaseLoader<UrlClick>();
  
    DatabaseSource dbSource = new DatabaseSource(SqlClientFactory.Instance,
                                                    connectionString,
                                                    commandText);
    IDataView dataView = loader.Load(dbSource);
  

• Enhanced .NET Core 3.0 Support

  • Use C# hardware intrinsics detection to support AVX, SSE and software fallbacks
  • Allows for faster training on AVX-supported machines
  • Allows for scoring core ML .NET models on ARM processors. (Note: some components do not support ARM yet, ex. FastTree, LightGBM, OnnxTransformer)

Bug Fixes

None.

Samples

• DeepLearning Image Classification Training sample (DNN Transfer Learning) (#633)
• DatabaseLoader sample loading an IDataView from SQL Server localdb (#611)

Breaking Changes

None

Enhancements

None.

CLI and AutoML API

• AutoML codebase has moved from feature branch to master branch (#3882).

Remarks

None.