A bit-rate adaptive coding system based on lossless DCT
In this paper, we propose a bit-rate adaptive coding system based on lossless DCT (L-DCT), Our adaptive coding system consists of three different operation modes: lossless. near-lossless and lossy coding modes. Quantization is applied in transform domain (after the L- DCT) and spatial domain (before the L-DCT) in lossy mode and near-lossless mode. respectively. Our adaptive coding system can automatically select its operation mode at a given bit rate because it contains a function to calculate the turning point between near-lossless mode and lossy mode from characteristic of input signal. Existence of the turning point is mathematically proved in this paper. Simulation results confirm not only effectiveness of our adaptive coding system but also accuracy of our theoretical analysis.
adaptive coding lossless near-lossless lossy lossless dct (l-dct)