Reconhecimento de fala
Definição
O reconhecimento de fala (ASR) transcreve áudio em texto. Related areas include speaker identification, speech synthesis (TTS), and spoken language understanding.
Ele faz a ponte entre multimodal (áudio como uma modalidade) e NLP (saída é texto). Modern ASR is mostly end-to-end neural; self-supervised pretraining (por ex. wav2vec 2.0) reduces the need for huge labeled datasets. Deployed in voice assistants, captions, and meeting tools.
Como funciona
Audio (waveform or mel spectrogram) is converted to features (por ex. filter banks, learned representations). An acoustic model (por ex. conformer, wav2vec 2.0 encoder) maps features to frame- or segment-level representations. A decoder (CTC, RNN-T, or attention-based) produces text (characters or subwords). Modern systems are often end-to-end (waveform or features → text in one model). Self-supervised pretraining on unlabeled audio (por ex. wav2vec) then fine-tuning on labeled ASR data improves robustness and reduces labeled data needs.
Casos de uso
Speech technologies apply when the input or output is audio: transcription, assistants, and speaker or synthesis systems.
- Automatic speech recognition (ASR) for transcription and captions
- Voice assistants and spoken dialogue systems
- Speaker identification and speech synthesis (TTS)