在对点像的探测中，无论采用空域还是时域处理，都只利用了点像元的部分信息，它们都具有一定的局限性。为此，本文提出一种融合多帧时空域滤波的点像元增强算法。首先利用改进后的Top-hat变换对多帧图像做空域处理，然后将具有较好频率分析优势的小波变换引入多帧图像中进行时域处理，最后利用联合分布概率把时空域两种处理方法所得到的灰度图进行融合。实验表明，增强后对具有空天背景的多帧图像平均灰度值和平均信噪比增益得到有效增强。

Both the spatial or time domain processing all have certain limitations by using only the partial infor-mation of the target. Therefore, this paper proposes an enhancement algorithm for low signal noise ratio point pixel based on time and spatial correlation. First, the improved Top-hat transform is used for image spatial pro-cessing, and then the wavelet transform, which has a good advantage of frequency analysis into the image, is in-troduced into the time domain processing. Finally, the joint probability distribution is adopted to integrate gray image obtained by the two processing methods. The experimental results show that the average grey value and SNR gain of target are enhanced effectively after enhancement.