ADAPTIVE GOP STRUCTURE TO H.264/AVC BASED ON SCENE CHANGE

Abstract

This paper proposes an adaptive GOP structure with the new logic of frame comparison in H.264/AVC to achieve better quality and reduce bit rate. Initially Group of Pictures (GOP) is set to a fixed size. Frames are compared within that GOP using correlation. According to the correlation, GOP is changed within that fixed size. So, there will be no GOP size greater than that fixed size. This method does not calculate any threshold. Hence the time needed to calculate global or local threshold is eliminated. It is integrated with conventional video codec H.264/AVC. This method is compared with H.264/AVC of fixed GOP structure of sizes 4, 8, 12, 16, 32 and GOP structure with the length of entire video. The proposed method achieved gain in bit rate from 0.49% to 69.75% and PSNR gain from 2.5% to 0.3%.

Keywords

• H.264/AVC
• GOP
• Correlation