Slice-Based Memory Reduction and Management for Storing Multiple Reference Frames of H.264 Video Codec

By utilizing multiple frames for motion estimation/compensation in H.264/AVC video codec, video coding becomes more efficient. However, the use of multiple reference frames also incurs an increase in the cost for storing these frames. By means of storing a portion of macroblocks (MBs) using compressed data, this work develops a scheme to reduce the memory cells required to store multiple reference frames. After analyzing the coding modes of MBs, the positions of their reference frames and the remaining memory space, the MBs of each slice in the current frame are appropriately determined to be stored as motion vectors (MVs), compressed or reconstructed data. Additionally, a memory management system is proposed to work together with the said memory reduction scheme and to allow the limited memory space to be utilized effectively. Experimental results reveal that, in comparison to the far-end frames dropped scheme, the proposed scheme in storing multiple reference frames not only achieves higher decoded video quality, it also has a flexible use of allocated memory space to minimize the computation required