METHOD AND SYSTEM FOR PROVIDING LOW COST ROBUST OPERATIONAL CONTROL OF VIDEO ENCODERS

摘要

In one aspect, the present invention discloses a simple low cost framework for robust operational control of video encoders. The framework comprises a two-layer architecture that effectively decouples the processes of video bit rate control and video quality/distortion control. The upper layer includes a video bit rate controller that operates on a single picture/picture-slice, or a set of pictures/picture-slices, and is based on feedback control techniques used in automatic control systems. The lower layer includes a video quality/distortion controller that operates at the level of blocks of pixels, and reduces distortion artifacts. The decoupled nature of the encoder control architecture of the present invention provides the flexibility of combining various feedback control algorithms and various distortion reduction schemes. In another aspect, the present invention discloses an efficient bit rate controller that serves as the upper layer of the operational control architecture, and is based on the proportional-integral-derivative (PID) technique used in automatic control systems. The bit rate controller relies on pure feedback of bit rate data and does not require rate-distortion modeling. In yet another aspect, the present invention discloses a simple and effective video quality/distortion controller that serves as the lower layer of the operational control architecture, and is based upon factors that directly influence the human visual system (HVS). The quality/distortion controller relies on very simple image distortion, complexity and activity metrics and does not depend upon rate-distortion optimization techniques. The low cost video encoder operational control architecture of the present invention may be used in connection with H.264 (ISO/IEC 14496-10) compliant video encoders as well as other video coding standards.