CAJ | 학술논문

传统的图像滤波器在模糊程度与去噪能力之间存在不可调和的矛盾.提出了一种基于时空域联合的方法,从视频的角度出发,同时利用信号的时域和空域相关性进行去噪,以解决这一矛盾.新方法首先通过一种基于自适应阈值、搜索方法切换的快速自适应运动估计方法获得运动轨迹,然后使用自适应窗口大小的中值滤波去除空域噪声,中值滤波中使用了运动轨迹上相邻两帧的对应窗口像素,使用一维卡尔曼滤波器行时域去噪,最后用几何均值结合两次滤波的结果,使信号的时域相关性与空域相关性都得到了充分利用.实验结果证明该算法去噪效果显著,超过了各种时域或空域方法,对椒盐噪声的处理效果尤其突出.实验也表明,由于新方法的时间消耗为时域滤波、空域滤波和运动估计时间的简单累加,因时空联合而增加的计算复杂度属于可接受的范围.
전통적도상려파기재모호정도여거조능력지간존재불가조화적모순.제출료일충기우시공역연합적방법,종시빈적각도출발,동시이용신호적시역화공역상관성진행거조,이해결저일모순.신방법수선통과일충기우자괄응역치、수색방법절환적쾌속자괄응운동고계방법획득운동궤적,연후사용자괄응창구대소적중치려파거제공역조성,중치려파중사용료운동궤적상상린량정적대응창구상소,사용일유잡이만려파기행시역거조,최후용궤하균치결합량차려파적결과,사신호적시역상관성여공역상관성도득도료충분이용.실험결과증명해산법거조효과현저,초과료각충시역혹공역방법,대초염조성적처리효과우기돌출.실험야표명,유우신방법적시간소모위시역려파、공역려파화운동고계시간적간단루가,인시공연합이증가적계산복잡도속우가접수적범위.
There is an irreconcilable conflict between the degree of vagueness and the capacity of denoising in conventional image filters.A new video based denoising method,combining special and temporal filters,utilizing both spatial correlation and temporal correlation,is proposed to solve this problem.At first the motion trajectory is gained by a fast adaptive motion estimation method with adaptive thresholds and different search modes.Then a window-size adaptive median filtering is performed with the two windows on the motion trajectory of current and last frame.The temporal redundancy is exploited by a scalar state 1-D Kalman filter.A novel way is proposed to estimate the variance of the state noise from the noisy frames.At last the two estimates are combined with a geometric mean take full advantage of both spatial and temporal relativities.Experimental result shows that the new method is robust than both spatial and temporal methods,especially when treating the pepper & salt noises.As the time consumption of the new method is sum of temporal filter,spatial filter and motion estimation,the computatiorial complexity increased by combination is acceptable,which is also proved in experiments.