In this study, an acceleration technique for non-separable oversampled lapped transforms (NSOLT) is proposed. NSOLT is a non-separable transform which simultaneously satisfies the oversampled, overlapped, symmetric, tight-frame, real-valued and compact-supported property. From the non-separability, NSOLT is valid for sparsely representing edges and textures with oblique directions as a linear generative model. In this paper, a fast convolution technique for NSOLT is proposed by using fast Fourier transform (FFT) and frequency-domain multirate processing. The analysis and synthesis processing for 2-D and 3-D data is evaluated through GPGPU implementation, and the processing speed of the proposed structure is compared with the conventional lattice-based one to show the effectiveness.
['Kota Horiuchi', 'Shogo Muramatsu']
Fast convolution technique for non-separable oversampled lapped transforms