CTranslate

CTranslate is a C++ implementation of OpenNMT's translate.lua script, with no Torch/Lua dependencies. It facilitates the use of OpenNMT models in existing products and on various platforms using Eigen as a backend.

It supports CPU OpenNMT models. You can convert GPU trained models with the release_model.lua script.

Dependencies

• C++11
• CMake
• Boost
• Eigen > 3.3

Compiling

$ mkdir build
$ cd build
$ cmake -DEIGEN_ROOT=<path to Eigen library> ..

It will produce the dynamic library libonmt.so and the translation client cli/translate.

To compile only the library, use the -DLIB_ONLY=ON flag.

Using

Client

See cli/translate --help. It has the same interface as the translate.lua script in OpenNMT while adding the ability to work with the standard input and output.

Library

This project is also a convenient way to load OpenNMT models and translate texts in existing software.

Here is a very simple example:

#include <iostream>

#include <onmt/TranslatorFactory.h>

int main()
{
  // Create a new Translator object.
  auto translator = onmt::TranslatorFactory::build("enfr_model_release.t7");

  // Translate a tokenized sentence.
  std::cout << translator->translate("Hello world !") << std::endl;

  return 0;
}

For a more advanced usage, see:

• include/onmt/TranslatorFactory.h to instantiate a new translator
• include/onmt/ITranslator.h to translate sequences or batch of sequences
• include/onmt/TranslationResult.h to retrieve results and attention vectors

Missing features

• OpenNMT tokenization and detokenization