TensorFlow Lite Extension to OpenNMT-tf Documentation

Since its release in 2017, the OpenNMT project has provided open development tools for Neural Machine Translation (NMT) including machine learning inference with artificial neural network models on Android platforms. Rapid advances in OpenNMT methods were achieved using TensorFlow since 2018; however, most of these advances were not deployable for use on Android platforms pending completion of the TensorFlow Lite library. The US Army Combat Capabilities Development Command Army Research Laboratory Shareable Components project team closely tracked progress on TensorFlow Lite and succeeded in implementing a new method for converting OpenNMT models from standard TensorFlow to the Lite variant. Deployable on Android devices, these converted models provide important gains in execution speed while occupying less space. A pull request submitted to the OpenNMT was approved and implemented in February 2021. This report describes how OpenNMT developers using TensorFlow can convert several types of models to TensorFlow Lite for use on Android platforms.