为进一步提高帧内预测的编码性能,提出一种新的帧内预测算法。算法对用于预测的参考像素进行相似度检测,当参考像素相似度高时,直接使用平均模式预测,省略了用于编码预测模式的比特,节省了码率,并减少了用于率失真优化所需的计算量,降低了计算复杂度;在各参考像素差异较大时,则按H.264/AVC中率失真优化的方法进行模式选择。实验结果表明,该算法在同样的峰值信噪比(PSNR)下,平均码率降低1.42%,编码速度提高了32.2%。
A novel intra prediction algorithm is proposed to improve the coding efficiency.The proposed method judges the overall similarity of the prediction pixels:In the case of high similarity,the Direct Current(DC) only mode is used,and it adaptively skips the prediction mode bits,which not only improves the coding efficiency,but also reduces the encoding complexity; otherwise,all the directional prediction modes are used and one of them is selected through RDO(Rate-Distortion Optimization) in H.264/AVC.Experimental results show that the proposed method achieves an average bit-rate reduction of 1.42% and encoding time reduction of 32.2% with the same Peak Signal Noise Ratio(PSNR).