2. The method of claim 1 , wherein obtaining the first batch of training frames that represent speech features of first training utterances comprises: obtaining, by a first decoder associated with the first sequence-training speech model, an utterance of the first training utterances; determining, by the first decoder, a reference score associated with the utterance; determining, by the first decoder, a training frame representing acoustic characteristics of the utterance based on the reference score.
2. The method of claim 1 , wherein obtaining the first batch of training frames that represent speech features of first training utterances comprises: obtaining, by a first decoder associated with the first sequence-training speech model, an utterance of the first training utterances; determining, by the first decoder, a reference score associated with the utterance; determining, by the first decoder, a training frame representing acoustic characteristics of the utterance based on the reference score. 4. The method of claim 2 , wherein obtaining the first batch of training frames that represent speech features of first training utterances comprises: determining, by the first decoder, a decoding score associated with the utterance, and wherein determining the training frame representing the acoustic characteristics of the utterance comprises determining, by the first decoder, the training frame representing the acoustic characteristics of the utterance based on the reference score and the decoding score.