Dependencies

1. flashlight

wav2letter++ uses flashlight as its core ML backend.

• Please follow the provided install procedures.
• wav2letter++ requires flashlight built with distributed training enabled (default).

2. KenLM

wav2letter++ uses KenLM to allow beam-search decoding with an n-gram language model.

• At least one of LZMA, BZip2, or Z is required for LM compression with KenLM.
• It is highly recommended to build KenLM with position-independent code (-fPIC) enabled, to enable python compatibility.
• After installing, run export KENLM_ROOT_DIR=... so that wav2letter++ can find it. This is needed because KenLM doesn't support a make install step.

Example build commands on Ubuntu:

sudo apt-get install liblzma-dev libbz2-dev libzstd-dev
git clone https://github.com/kpu/kenlm.git
cd kenlm
mkdir -p build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release -DKENLM_MAX_ORDER=20 -DCMAKE_POSITION_INDEPENDENT_CODE=ON
make -j16
# don't forget to export KENLM_ROOT_DIR

3. Additional Dependencies

The following additional packages are required:

• Any CBLAS library, i.e. at least one of these:
  • ATLAS
  • OpenBLAS
  • Accelerate
  • Intel MKL (used preferentially if present)
• FFTW3
• libsndfile
  • Should be built with Ogg, Vorbis, and FLAC libraries.
• gflags
• glog

Example (Ubuntu). The following command will install all the above packages:

apt-get install libsndfile1-dev libopenblas-dev libfftw3-dev libgflags-dev libgoogle-glog-dev

4. Optional Notes

The following dependencies should be already installed for flashlight:

• A C++ compiler with good C++11 support (e.g. g++ >= 4.8)
• cmake >= 3.5.1, and make
• CUDA >= 9.2, only if using CUDA backend

The following dependencies are automatically downloaded and built by cmake:

• gtest and gmock 1.8.1, only if building tests
• CUB 1.8.0, only if using CUDA backend

The following dependencies are optional:

• OpenMP, if present, will be used for better performance.