视频缓冲器的自适应控制

ADAPTIVE CONTROL OF VIDEO BUFFERS

视频缓冲器是可变输出位率编码器和恒定速率信道之间的接口设备，它的设计是多媒体通信领域重要的研究课题．本文提出一种自适应缓冲器控制方法．这种方法在确定量化参数过程中，不仅要参考缓冲器的占空度，而且还要考虑图象序列和编码器的统计特性．利用这种方法调节编码器输出位率，可以有效地避免缓冲器的上溢和下溢，并且保证图象质量的渐进过渡．

The design of the video buffer interfacing a variable output bitrate encoder to a constant rate channel is essential in the field of multimedia communication. This paper presents an adaptive buffer control method which exploits statistical information about input images and encoder modes along with observation of buffer occupancy in the determination of quantitized parameters. Buffer overflow/underflow problems can be avoided and progressive quality transition of encoded images can be guaranteed using the proposed method to adjust the output bitrate of the video encoder.