Tiled-Block Image Reconstruction by Wavelet- Based, Parallel-Filtered Back-Projection

We demonstrate an algorithm, relevant to tomography sensor systems, to obtain images from the parallel reconstruction of essentially localized elements at different scales. This is achieved by combining methodology to reconstruct images from limited and/or truncated data, with the time-frequency capabilities of the wavelet transform. Multiscale, as well as time-frequency, localization properties of the separable two-dimensional wavelet transform are exploited as an approach for faster reconstruction. The speedup is realized not only by reducing the computation load on a single processor, but also by achieving the parallel reconstruction of several tiled blocks. With tiled-block image reconstruction by wavelet-based, parallel filtered back-projection (FBP), we measure more than 36 times gain in speed, compared with standard FBP.