Lossless and Near-Lossless L-Infinite Compression of Depth Video Data

Depth information acquisition is critically important in medical applications, such as monitoring of elderly or human biometrics extraction. In such applications, compressing the stream of depth video data plays an important role due to bandwidth constraints on the transmission channels. This paper introduces a novel lightweight compression system that encodes the semantics of the input depth video and can operate in both lossless and L-infinite near-lossless compression modes. A quantization technique that targets the L-infinite norm for sparse distributions and a new L-infinite compression method that sets bounds on the quantization error are proposed. The proposed codec enables controlling the coding error on every pixel in the input video data, which is crucial in medical applications. Experimental results show an average improvement of 45% and 17% in lossless mode compared to standalone JPEG-LS and CALIC codecs, respectively. Furthermore, in near-lossless mode, the proposed codec achieves superior rate-distortion performance and reduced maximum error per frame compared to HEVC. Additionally, the proposed lightweight codec is designed to perform efficiently in real time when deployed on an embedded depth camera platform.