One open source speech-to-text library that is known for its high level of accuracy is the Kaldi toolkit. Kaldi is a free, open-source software for speech recognition that is widely used in research and industry. It is designed to be flexible, scalable, and easily customizable, allowing developers to train models on their own data and fine-tune them for specific applications.

Kaldi uses a range of advanced techniques, such as deep neural networks, to achieve high accuracy in speech recognition. It also supports a wide range of features, including speaker diarization, keyword spotting, and speech activity detection, making it a comprehensive toolkit for speech recognition.

Kaldi is written in C++ and provides a command-line interface for training and testing speech recognition models. It is compatible with a range of operating systems, including Linux, macOS, and Windows.

Note that while Kaldi is known for its high accuracy, achieving good results with any speech-to-text library requires careful data preparation, model training, and tuning, as well as testing and evaluation.
spam fails_task lang_mismatch pii not_appropriate hate_speech sexual_content quality toxicity humor helpfulness creativity violence