pherkel/swr2-asr

Spoken Word Recognition Course

SWR2-ASR

Automatic speech recognition model for the seminar "Spoken Word Recogniton 2 (SWR2)" by Konstantin Sering in the summer term 2023.

Authors: Silja Kasper, Marvin Borner, Philipp Merkel, Valentin Schmidt

Dataset

We use the german multilangual librispeech dataset (mls_german_opus). If the dataset is not found under the specified path, it will be downloaded automatically.

If you want to train this model on custom data, this code expects a folder structure like this:

<dataset_path>
  ├── <language>
  │  ├── train
  │  │  ├── transcripts.txt
  │  │  └── audio
  │  │     └── <speakerid>
  │  │        └── <bookid>
  │  │           └── <speakerid>_<bookid>_<chapterid>.opus/.flac
  │  ├── dev
  │  │  ├── transcripts.txt
  │  │  └── audio
  │  │     └── <speakerid>
  │  │        └── <bookid>
  │  │           └── <speakerid>_<bookid>_<chapterid>.opus/.flac
  │  └── test
  │     ├── transcripts.txt
  │     └── audio
  │        └── <speakerid>
  │           └── <bookid>
  │              └── <speakerid>_<bookid>_<chapterid>.opus/.flac

Installation

The preferred method of installation is using poetry. After installing poetry, run

poetry install

to install all dependencies. poetry also enables you to run our scripts using

poetry run SCRIPT_NAME

Alternatively, you can use the provided requirements.txt file to install the dependencies using pip or conda.

Usage

Tokenizer

We include a pre-trained character-level tokenizer for the german language in the data/tokenizers directory.

If the path to the tokenizer you specified in the config.yaml file does not exist or is None (~), a new tokenizer will be trained on the training data.

Decoder

There are two options for the decoder:

• greedy
• beam search with language model

The language model is a KenLM model and supplied by the multi-lingual librispeech dataset. If you want to use a different KenLM language model, you can specify the path to the language model in the config.yaml file.

Training the model

All hyperparameters can be configured in the config.yaml file. The main sections are:

• model
• training
• dataset
• tokenizer
• checkpoints
• inference

Train using the provided train script:

poetry run train \
--config_path="PATH_TO_CONFIG_FILE"

You can also find our model that was trained for 67 epochs on the mls_german_opus here.

Inference

The config.yaml also includes a section for inference. To run inference on a single audio file, run:

poetry run recognize \
--config_path="PATH_TO_CONFIG_FILE" \
--file_path="PATH_TO_AUDIO_FILE" \
--target_path="PATH_TO_TARGET_FILE"

Target path is optional. If not specified, the recognized text will be printed to the console. Otherwise, a WER will be computed.