This paper describes a 3-D band-limitation technique for a video signal based on motion adaptive spatial filtering. Under the assumption that the spatial and temporal filters are separable, 3-D filtering is implemented by a cascade combination of temporal filter and spatial filter. Temporal filtering can be performed using the Motion Adaptive Spatial Filter (MASF) in the spatial domain[1]. Thus, 3-D filtering can be performed in the spatial domain.
In this paper, the method to design the MASF in the frequency domain is proposed. And considering the pass-band of the spatial filter in designing the MASF, the impulse response of the 3-D filter is obtained in the spatial domain. It means that the MASF as a temporal filter is extended to the 3-D filter. Therefore the proposed 3-D filter requires only one frame and its motion vectors.
The proposed 3-D filtering scheme has the properties that temporal aliasing is reduced and less memory than conventional schemes in hardware implementation is required. The simulation results for image sequence with constant motion inform explicitly that this scheme has temporal de-aliasing property and 3-D band-limitation is achieved in spatial domain. Under assumption of constant-velocity rigid-translational motion, this 3-D filtering scheme can be applied to real image sequence.
