This paper presents a selective quality control system to be able to accurately control the relative picture quality among the video programs in terms of PSNR. The proposed system allows variable bit rate (VBR) for each video program to maintain the pre-determined relative picture quality among the aggregated video programs while keeping a constant sum of the bit rates for all programs to be transmitted over a single constant bit rate (CBR) channel. This is achieved by simultaneous controlling the video encoders to generate VBR video streams at the central controller. Furthermore, we also suggest buffer regulation method based on the analysis of the constraints imposed by sender/receiver buffer sizes and total transmission rate. Through various simulation results, it is found that the proposed quality control system guarantees that the video buffers neither overflow nor underflow and the quality control errors do not exceed 0.1 dB.
['Hong-Yoen Yu', 'Aaron Park', 'Keun Won Jang', 'Jin Park', 'Seong-Joon Baek', 'Dong Kook Kim', 'Young-Chul Kim', 'Sung-Hoon Hong']
Selective quality control of multiple video programs for digital broadcasting services