Yichen Ouyang, Lu Wang, Fangkai Yang, Pu Zhao, Chenghua Huang, Jianfeng Liu, Bochen Pang, Yaming Yang, Yuefeng Zhan, Hao Sun, Qingwei Lin, Saravan Rajmohan, Weiwei Deng, Dongmei Zhang, Feng Sun. Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing. 2025.

With the increasing demand for high-resolution video and real-time processing, the limited efficiency of video-denoising algorithms has become a critical factor. This paper proposes a spatio-temporal video denoising co-processor to suppress an image sequence’s spatial and temporal noise. Temporal denoising is achieved by merging the current and previous frames at the pixel level in which the current frame is processed by a spatial filter. After exploiting noise estimation and motion detection, the Wiener filter calculates the merge ratio. Rather than buffering the entire previous frame, the JPEG-like codec can dynamically adjust the compression ratio through a predefined quantization table to satisfy the designed on-chip storage. The experimental results demonstrate that the spatio-temporal denoising co-processor can effectively eliminate the fluctuation of the grayscale value of the noise in videos. Simultaneously, the adaptive codec can reduce the storage space consumption for the frame buffer by at least 80% of the original size. To the best of our knowledge, this is the first fully integrated spatio-temporal denoising co-processor without any external memory. Additionally, the grayscale, RGB, and RAW versions of the co-processor are also implemented on the Stratix V FPGA platform and synthesized in 28nm CMOS technology.