Miscellaneous Topics

File Systems

The FileSystem architecture supports multiple file systems through an interface that is chosen by URI. There is built-in support for: local and HTTP file systems in the rastervision.pipeline package, AWS S3 in the rastervision.aws_s3 plugin, and any file that can be opened using GDAL VSI in the rastervision.gdal_vsi plugin. Some file systems support read only (HTTP), while others are read/write. If you need to support other file storage systems, you can add new FileSystem classes via a plugin.

Viewing Tensorboard

The PyTorch backends included in the rastervision.pytorch_backend plugin will start an instance of TensorBoard while training if log_tensorboard=True and run_tensorboard=True in the BackendConfig. To view TensorBoard, go to https://<domain>:6006/. If you’re running locally, then <domain> should be localhost, and if you are running remotely (for example AWS), <domain> is the public DNS of the machine running the training command. If running locally, make sure to forward port 6006 using the --tensorboard option to docker/run if you are using it. At the moment, basic metrics are logged each epoch, but more interesting visualization could be added in the future.

Transfer learning using models trained by RV

To use a model trained by Raster Vision for transfer learning or fine tuning, you can use output of the TRAIN command of the experiment as a pretrained model of further experiments. The last_model.pth model file in the train directory can be used as a pretrained model in a new pipeline. To do so, set the init_weights field to the model file in the ModelConfig in the new pipeline.

Making Predictions with Model Bundles

To make predictions on new imagery, the bundle command generates a “model bundle” which can be used with the predict command. This loads the model and saves the predictions for a single scene. If you need to call this for a large number of scenes, consider using the Predictor class programmatically, as this will allow you to load the model once and use it many times. This can matter a lot if you want the time-to-prediction to be as fast as possible - the model load time can be orders of magnitudes slower than the prediction time of a loaded model.

The model bundle is a zip file containing the model weights and the configuration necessary for Raster Vision to use the model. This configuration includes the configuration of the model architecture, how the training data was processed by RasterTransformer, the subset of bands used by the RasterSource, and potentially other things. The model bundle holds all of this necessary information, so that a prediction call only needs to know what imagery it is predicting against.

This works generically over all models produced by Raster Vision, without additional client considerations, and therefore abstracts away the specifics of every model when considering how to deploy prediction software. Note that this means that by default, predictions will be made according to the configuration of the pipeline that produced the model bundle. Some of this configuration might be inappropriate for the new imagery (such as the channel_order), and can be overridden by options to the predict command.