Scene adaptive bit-rate control method on MPEG video coding
Scene adaptive bit-rate control method on MPEG video coding
复制标题
MPEG视频编码的场景自适应码率控制方法
DOI：
10.1117/12.263221
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Jae
中科院分区：
文献类型：
--
作者：
Myungjin Lee;Soon;Jae
本文提出了一种简单的码率控制方法，以百分比的突然质量下降后，场景变化。在场景改变之后，由于场景改变之前和之后的图片之间的差的时间预测而发生质量降级。利用DCT变换前的空间方差和频谱平坦度来预测图像的编码复杂度。从预测的编码复杂度，我们表明，率失真的图像的关系可以近似为指数函数。当场景变化时，使用每个P-图像的率失真关系，在使GOP中的失真最小化的方向上调整图像目标比特。由于可能出现比特短缺，所提出的方法将当前GOP扩展到下一个。该算法可以很容易地应用于现有的MPEG编解码器和实时应用。与MPEG-2 TM 5码率控制算法相比，该算法在PSNR上有0.5 ~ 2.5dB的增益，并且在场景变换后图像质量波动较小。
This paper presents a simple bitrate control method to percent the abrupt quality degradation after scene change. After scene change, the quality degradation occurs due to the poor temporal prediction between pictures before and after scene change. We predict the coding complexity of picture using the spatial variance before DCT and spectral flatness measure. From the predicted coding complexity, we show that the rate-distortion relation of image can be approximated to exponential function. When scene changes, picture target bit is adjusted in the direction to minimize the distortion in a GOP using the rate-distortion relations for each P-picture. Since the bit shortage could be occurred, proposed method extends the current GOP to the next. The algorithm can be applied to the existing MPEG codecs and real-time applications easily. Compared with the MPEG-2 TM5 rate control algorithm, proposed algorithm shows 0.5 to approximately 2.5 dB gain in PSNR and a small fluctuation in quality after scene change.