Study of a lossless video coding algorithm based on H.26L tools

In this paper, we demonstrate the performance of a lossless video-coding algorithm based on the existing H.26L test model. The lossless coding algorithm is formed by simply skipping the transform and quantization operations in H.26L; therefore, the main elements in this lossless coding algorithm are motion compensation, Intra prediction, and entropy coding tools of H.26L. It has been demonstrated that H.26L has significant good performance at both low bit rates and high bit rates for lossy video coding. Here we further demonstrate the competitive performance of lossless video coding using H.26L tools. The H.26L lossless video coding results are compared to those of Motion JPEG2000. When Inter coding tool is applied, H.26L provides on average 32% bit reduction comparing to Motion JPEG2000. We evaluate the performances of H.26L Intra and Inter coding separately. The motion compensation techniques adopted in H.26L proves to be also effective for lossless coding. There is roughly 40% bit saving when Inter frame coding is turned on. The performance of Intra prediction of H.26L for lossless coding is not as impressive as that of the H.26L motion compensation; the bitrate increases on average by 19% comparing to that of Motion JPEG2000, which also uses only Intra coding tools. The results indicate that H.26L Intra coding could further be improved. Possible improvements for H.26L lossless video coding are suggested in the paper.