In this work an efficient format-compliant encryption approach for regular languages is proposed, block-based cycle-walking. The approach can transparently trade-off security for efficiency and can be adjusted to the desired level of security. The relationship between the encryption of regular languages and the encryption of JPEG2000 bitstreams is established. Block-based cycle-walking for the ...

In this paper, we investigate the error resilience properties of JPEG2000. Through a careful analysis of the structure of JPEG2000 codestreams, we identify the dependencies among coding passes of a codeblock. In our analysis, we consider the effects of mode variations provided by the standard for low-memory, low-complexity implementations. The proposed methods are derived using the existing dep...

This paper describes work which investigates how the Large Hadron Collider (LHC) Computing Grid (LCG) can be used to upload, store, compress and download satellite image data files on behalf of the United Nations Organization UNOSAT. Mechanisms for satellite image upload, storage and download are outlined. LCG computational resources are exercised by a JPEG2000 compression framework that transf...

We address the problem of compression for large camera arrays, and propose a distributed solution based on Wyner-Ziv coding. The proposed scheme allows independent encoding of each view with low-complexity cameras, and performs centralized decoding with side information from additional views. Experimental results are given for two light field data sets. The performance of the proposed scheme is...

We propose a framework for iterative joint sourcechannel decoding of JPEG2000 codestreams. At the encoder, JPEG2000 is used to perform source coding with certain error resilience (ER) modes, and LDPC codes are used to perform channel coding. During decoding, the source decoder uses the ER modes to identify corrupt sections of the codestream and provides this information to the channel decoder. ...

In JPEG2000 block coding, all coding passes are generated before rate allocation is performed among code blocks. Unwanted passes are then discarded. For low bit-rate coding, this results in a large number of coding passes being discarded. A rate-distortion estimation method that enables precompression rate-distortion optimisation to be carried out, wherein only the required passes need to be co...

In JPEG2000 block coding, all coding passes are generated before rate allocation is performed among code-blocks. Unwanted passes are then discarded. For low bit-rate coding, this results in discarding of a large number of coding passes. In this letter, we propose a rate-distortion estimation method that enables pre-compression rate-distortion optimization to be carried out, wherein only the req...