A new rate control scheme using quadratic rate distortion model
A new rate control scheme using quadratic rate distortion model
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DOI：
10.1109/icip.1996.560604
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发表时间：
1996-09
期刊：
影响因子：
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通讯作者：
Tihao Chiang;Ya-Qin Zhang
中科院分区：
文献类型：
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作者：
Tihao Chiang;Ya-Qin Zhang
新的速率控制方案用于根据速率失真函数的二次公式计算每个帧的目标比特率。假定失真度量是框架的平均量化标尺或均方根误差。速率失真函数被建模为失真度量倒数的二阶函数。我们为目标位分配提供了一个封闭的形式解决方案，该解决方案适用于数字存储介质（DSM）应用程序（例如MPEG-2）和非常低的比特率（VLBR）应用程序（例如MPEG-4）。我们在基于小波的编码器上执行实验，以证明我们方案的多功能性。使用统计线性回归分析估算模型参数。由于该估计使用了同一图片预测类型的过去编码帧（I，P和B图片），因此所提出的方法是单个通过速率控制技术。对于MPEG-2编码器，在位计数的标准偏差中，位计数的波动显着降低了20％至65％，而图片质量保持不变。对于MPEG-4 VM编码器，与使用量化标度参数的详尽组合相比，与最佳MPEG-4 VM速率控制相比，PSNR几乎可以提高一个DB。
A new rate control scheme is used to calculate the target bit rate for each frame based on a quadratic formulation of the rate distortion function. The distortion measure are assumed to be either the average quantization scale of a frame or mean square error. The rate distortion function is modeled as a second order function of the inverse of the distortion measure. We presented a closed form solution for the target bit allocation which applies to both the digital storage media (DSM) applications (e.g., MPEG-2) and very low bit rate (VLBR) applications (e.g., MPEG-4). We perform experiments on a wavelet-based coder to demonstrate the versatility of our scheme. Model parameters are estimated using statistical linear regression analysis. Since the estimation uses the past encoded frames of the same picture prediction type (I, P and B pictures), the proposed approach is a single pass rate control technique. For the MPEG-2 coder the fluctuations of the bit counts are significantly reduced by 20 percent to 65 percent in the standard deviation of the bit count while the picture quality remains the same. For the MPEG-4 VM coder, the PSNR is improved by almost one dB as compared to the best MPEG-4 VM rate control using exhaustive combinations of quantization scale parameters.