Compression and protection of multidimensional data

2013 - 2014The main objective of this thesis is to explore and discuss novel techniques related to the compression and protection of multidimensional data (i.e., 3-D medical images, hyperspectral images, 3-D microscopy images and 5-D functional Magnetic Resonance Images). First, we outline a lossless compression scheme based on the predictive model, denoted as Medical Images Lossless Compression algorithm (MILC). MILC is characterized to provide a good trade-off between the compression performances and reduced usage of the hardware resources. Since in the medical and medical-related fields, the execution speed of an algorithm, could be a “critical” parameter, we investigate the parallelization of the compression strategy of the MILC algorithm, which is denoted as Parallel MILC. Parallel MILC can be executed on heterogeneous devices (i.e., CPUs, GPUs, etc.) and provides significant results in terms of speedup with respect to the MILC. This is followed by the important aspects related to the protection of two sensitive typologies of multidimensional data: 3-D medical images and 3-D microscopy images. Regarding the protection of 3-D medical images, we outline a novel hybrid approach, which allows for the efficient compression of 3-D medical images as well as the embedding of a digital watermark, at the same time. In relation to the protection of 3-D microscopy images, the simultaneous embedding of two watermarks is explained. It should be noted that 3-D microscopy images are often used in delicate tasks (i.e., forensic analysis, etc.). Subsequently, we review a novel predictive structure that is appropriate for the lossless compression of different typologies of multidimensional data... [edited by Author]XIII n.s

Protection of microscopy images through digital watermarking techniques

Nowadays microscopy confocal images are becoming more and more a fundamental tool for many application fields, including biology, forensic analysis, medicine, industrial research, etc.. Therefore, as it is easy to note, given the contexts in which such images have to operate, their protection, or at least their non alterability, is a very challenging problem in many fields. Although these problems are deeply felt, in the state of the art does not exist digital watermarking techniques for such types of images. In this paper, we propose a novel scheme well-suited for the embedding of digital watermarks into confocal microscopy image sequences. This work, to the best of our knowledge is the first one which addresses the protection of such images type. The preliminary test results show that the scheme we propose is fairly resistant against the lossy compression attack, by providing a good trade-off between robustness and computational complexity