This paper proposes singing voice synthesis (SVS) based on frame-level sequence-to-sequence models considering vocal timing deviation. In SVS, it is essential to synchronize the timing of singing with temporal structures represented by scores, taking into account that there are differences between actual vocal timing and note start timing. In many SVS systems including our previous work, phoneme-level score features are converted into frame-level ones on the basis of phoneme boundaries obtained by external aligners to take into account vocal timing deviations. Therefore, the sound quality is affected by the aligner accuracy in this system. To alleviate this problem, we introduce an attention mechanism with frame-level features. In the proposed system, the attention mechanism absorbs alignment errors in phoneme boundaries. Additionally, we evaluate the system with pseudo-phoneme-boundaries defined by heuristic rules based on musical scores when there is no aligner. The experimental results show the effectiveness of the proposed system.

翻译：本文提出了一种基于帧级序列到序列模型且考虑发声时间偏差的歌声合成方法。在歌声合成中，必须使歌唱时间与乐谱表示的时序结构同步，同时考虑实际发声时间与音符起始时间之间的差异。在包括我们先前工作在内的许多歌声合成系统中，基于外部对齐器获得的音素边界将音素级乐谱特征转换为帧级特征，以考虑发声时间偏差。因此，此类系统的音质受对齐器精度影响。为缓解这一问题，我们引入了带帧级特征的注意力机制。在提出的系统中，注意力机制能够吸收音素边界的对齐误差。此外，当无对齐器时，我们基于乐谱启发式规则定义伪音素边界，并对系统进行了评估。实验结果表明了所提系统的有效性。