VideoDubber: Machine Translation with Speech-Aware Length Control for Video Dubbing

TL;DR

This paper introduces a speech-aware machine translation system for video dubbing that explicitly controls the length of translated speech by considering speech duration, leading to better alignment with the original video timing.

Contribution

The proposed system directly incorporates speech duration information into translation, improving length control for video dubbing over traditional word or character-based methods.

Findings

Achieves superior length control in translated speech compared to baselines.

Demonstrates effectiveness across four language pairs.

Constructs a real-world dataset for comprehensive evaluation.

Abstract

Video dubbing aims to translate the original speech in a film or television program into the speech in a target language, which can be achieved with a cascaded system consisting of speech recognition, machine translation and speech synthesis. To ensure the translated speech to be well aligned with the corresponding video, the length/duration of the translated speech should be as close as possible to that of the original speech, which requires strict length control. Previous works usually control the number of words or characters generated by the machine translation model to be similar to the source sentence, without considering the isochronicity of speech as the speech duration of words/characters in different languages varies. In this paper, we propose a machine translation system tailored for the task of video dubbing, which directly considers the speech duration of each token in translation, to match the length of source and target speech. Specifically, we control the speech length of generated sentence by guiding the prediction of each word with the duration information, including the speech duration of itself as well as how much duration is left for the remaining words. We design experiments on four language directions (German -> English, Spanish -> English, Chinese <-> English), and the results show that the proposed method achieves better length control ability on the generated speech than baseline methods. To make up the lack of real-world datasets, we also construct a real-world test set collected from films to provide comprehensive evaluations on the video dubbing task.