Low Latency ASR for Simultaneous Speech Translation
This addresses the need for low-latency translation in real-time applications like lecture translation, representing an incremental improvement over existing methods.
The paper tackled the problem of high latency in simultaneous speech translation by focusing on word-level latency, reducing it from 18.1 seconds to 1.1 seconds without increasing word error rate.
User studies have shown that reducing the latency of our simultaneous lecture translation system should be the most important goal. We therefore have worked on several techniques for reducing the latency for both components, the automatic speech recognition and the speech translation module. Since the commonly used commitment latency is not appropriate in our case of continuous stream decoding, we focused on word latency. We used it to analyze the performance of our current system and to identify opportunities for improvements. In order to minimize the latency we combined run-on decoding with a technique for identifying stable partial hypotheses when stream decoding and a protocol for dynamic output update that allows to revise the most recent parts of the transcription. This combination reduces the latency at word level, where the words are final and will never be updated again in the future, from 18.1s to 1.1s without sacrificing performance in terms of word error rate.