中文摘要：

MPEG-4FGS是MPEG-4中精细可扩展性编码方法，由于采用帧8＊8交织的位平面编码结构，无法支持帧内区域级的动态码率分配，不适合基于内容的增强和流化传输，针对MPEG-4FGS这编码限制，本文根据MPEG-7的内容描述标准，提出了一种基于帧内区域的细粒度可扩展A—FGS编码，实现了实时的帧内区域流化编码，并就该编码提出了一种最优码率分配算法．利用帧内区域8＊8宏块高位平面非零系数很少的特点，提出了动态码率分配算法，使在中等码率范围内编码效率提高了0．5dB左右．

英文摘要：

MPEG-4 FGS is a fine-grain scalable coding method for MPEG-4. The 8 ＊ 8 flame interlaced bit-plane coding structure used by the MPEG-4 FGS coding does not support intra-frame dynamic bit rate allocation, and therefore is incapable of supporting content-based streaming transport. Regarding the limitation of the MPEG-4 FGS coding, we propose an intra-frame finegranular scalable coding method （A-FGS） based on the MPEG-7 content description standard to achieve the goal of real-time intra-frame streaming coding.An optimal bit rate allocation algorithm is also provided for the A-FGS coding method.By using the characteristic of having few non-zero coefficient in the intra-frame 8 ＊ 8 macro-block high bit-plane, we apply a dynamic bit rate allocation method to improve the coding efficiency in mid bit rate range by about 0.5dB.