Efficient Semantic Codec for Real-time Vibrotactile Transmission

Nowadays, haptic data has gained a fast-growing volume with enormous interaction points during human-computer interaction and embodied AI. In the near future, the massive haptic signals -encompassing both kinesthetic and vibrotactile signals- will place significant demands on both communication and computing resources. To address this challenge, we propose the first task-oriented sematic codec of low-delay vibrotactile transmission, namely, vibrotactile semantic codec (VTSC). Specifically, we design a perception-based vibrotactile semantic extraction mechanism (PSEM) that considers the high and low thresholds of vibrotactile perception in effective semantic coding while adhering to the low delay constraint. Inspired by this principle, we then propose a vibrotactile semantic encoder (VSE) with local and global semantic extractors, which can efficiently extract and preserve semantic features within the short frame context. Besides, we present a semantic distribution loss function to enhance the learning of meaningful representations. Comprehensive experiments demonstrate the superiority of our VTSC, achieving significantly higher task accuracy than the state-of-the-art vibrotactile codecs at the same compression ratio (CR), e.g. 60% improvement when CR=256. When compared to transferred audio-visual sematic codecs, our VTSC also shows promising improvements, validating the effectiveness our approach.