Evaluation of Different Training Strategies and Recognizers in Low Resource Speech Recognition Using Wav2vec2.0
摘要
Automatic Speech Recognition (ASR) is crucial for preserving minority languages, promoting inclusivity, and supporting education. Wav2vec2.0 Model, pre-trained through self-supervised learning, is effective for low-resource language speech recognition. Thus, this study investigates different learning strategies, recognizers, and frameworks to improve ASR performance for low-resource languages. First, we compared five learning strategies for low-resource language speech recognition using the wav2vec2.0 model. The Freeze-Transformer strategy, which fixes the CNN and low-layer Transformer blocks, achieved the lowest Character Error Rate (CER). Next, we evaluated five types of recognizers, including fully connected layers, MLP, RNN, LSTM, and GRU. The bi-GRU recognizer performed the best, achieving the lowest CER. Finally, we tested an Encoder-Decoder model with wav2vec2.0 as the encoder and a Transformer-decoder as the decoder. The results showed that the recognition performance did not improve with this model, even with a large amount of training data.