Differential semantic communications for salient object transmission in 6G multimedia systems

Emerging paradigms lack a generalised feedbacked model that addresses factors such as bandwidth usage, information scheduling, and performance evaluation. To tackle them, we theorise Differential Semantic Communications, abbreviated DSCs, inspired by human-like natural communications. A DSC model employs a closed-loop feedback architecture, where two intelligent transceiver agents interact cyclically to achieve a communication goal. We introduce a top-down information representation to enable iterative transmissions. Visual salient object transmission is demonstrated as a proof-of-concept application for DSCs. A novel performance metric, termed semantic misfit-percent, is also derived to evaluate the efficiency of data-and-information reconstruction. Simulation results show the ability of salient object transmission in images with about 9 % misfit improvement on average compared to the state-of-the-art DALL.E1-based approach. Implementation codes are available upon request.