Motion-adaptive sub-Nyquist sampling technique for multi-frame super-resolution

We have developed a motion-adaptive sub-Nyquist sampling technique to be used as a complement to super-resolution (SR) image reconstruction. These techniques are used together for pre- and post-processing with a conventional video codec (core codec). In this new video coding system, called “reconstructive video coding,” the sub-sampling process reduces the core codec's compression ratio, thereby reducing such nonlinear distortion as block noise. On the decoder side, the decimated pixels are replenished with ones from neighboring frames through a multi-frame SR technique that compensates for inter-frame local motion. As a preliminary design study, we developed a systematic procedure (a sub-sampler) for a spatiotemporal allocation of sampling points to cover the objects in a scene as uniformly as possible by taking into account their motions. Testing of this procedure in combination with a multi-frame SR technique demonstrated that the proposed sub-Nyquist sampling technique is more effective than simple non-adaptive sub-sampling.