CAJ | 학술논문

　　提出了一种2 bit深度像素的运动估计算法。首先，将像素深度的降采样过程形式化为区间分划和区间映射2个步骤，其中前者为多对一映射，决定着运动估计性能，后者为一一映射；其次，提出一种非均匀量化方法求解区间分划的3个初始阈值，并利用隶属度函数对初始阈值细化，从而克服信号噪声等因素导致的初始阈值周围像素值的误匹配；再次，讨论了适用于2 bit深度像素运动估计的误差度量准则，进而提出了基于模糊量化和2 bit深度像素的运动估计算法；最后，借助信号自相关函数，建立比特深度转换误差—运动向量精度模型来估计该算法所能达到的预测精度。实验结果证明，对于多种类型的视频序列，尤其是场景细节和物体运动比较复杂者，该算法始终能保持较高的估计精度，运动补偿的平均峰值信噪比较之传统2 bit深度像素的运动估计提高0.27 dB。
　　제출료일충2 bit심도상소적운동고계산법。수선，장상소심도적강채양과정형식화위구간분화화구간영사2개보취，기중전자위다대일영사，결정착운동고계성능，후자위일일영사；기차，제출일충비균균양화방법구해구간분화적3개초시역치，병이용대속도함수대초시역치세화，종이극복신호조성등인소도치적초시역치주위상소치적오필배；재차，토론료괄용우2 bit심도상소운동고계적오차도량준칙，진이제출료기우모호양화화2 bit심도상소적운동고계산법；최후，차조신호자상관함수，건립비특심도전환오차—운동향량정도모형래고계해산법소능체도적예측정도。실험결과증명，대우다충류형적시빈서렬，우기시장경세절화물체운동비교복잡자，해산법시종능보지교고적고계정도，운동보상적평균봉치신조비교지전통2 bit심도상소적운동고계제고0.27 dB。
A motion estimation algorithm was proposed using 2 bit-depth pixels. The reduction of pixel depth was first formalized by two successive steps, namely interval partitioning and interval mapping. The former is a many-to-one mapping which determines motion estimation performance, while the latter is a one-to-one mapping. A non-uniform quantization method was then presented to compute three initial thresholds of the interval partitioning. These initial thresholds were subsequently refined by using a membership function to solve the mismatch of pixel values near them caused by signal noise and so on. Afterwards, a matching criterion was discussed suitable for the motion estimation using 2 bit- depth pixels. A novel motion estimation algorithm was consequently addressed based on 2 bit-depth pixels and fuzzy quantization. To further predict the precision of the proposed algorithm, a bit resolution reduction error-motion vector precision model was built by exploiting the auto-correlation function. Extensive experimental results show that the pro-posed algorithm can always achieve high motion estimation precision for video sequences with various characteristics, especially for those with detailed scene and complex motion. Compared with traditional 2 bit motion estimation, the pro-posed algorithm gains 0.27 dB improvement in terms of average peak signal-to-noise ratio of motion compensation.