In this paper, a reversible data hiding scheme based on a Vector Quantization (VQ) index table is proposed. To satisfy different needs of users, our proposed scheme is designed with flexibility in adjusting hiding capacity and compression rate. First, the codebook is rearranged referring to the index occurrence frequency in the VQ index table. After that, the codewords in the newly generated co...

This paper presents a new method of lossless data compression called LZPP, being an advanced modification of the well-known algorithm LZSS [1]. It introduces improvements of the LZ family algorithms [2, 3], such as the use of a special coding of two and three byte matches, use of an auxiliary entropy coder and new criteria of symbol exclusions. Minimization of the data compression ratio (bpc) h...

Contrary to convention, we construct distributed image compression codecs that operate in the pixel-domain, yet exploit spatial correlation at the decoder only. For lossless compression of binary images of text, we propose two novel decoders: one assumes the image to be a one-dimensional stationary Markov process, and the other assumes it to be a two-dimensional stationary Markov random field. ...

Ultrafast electron diffraction (UED) is a powerful method for studying time-resolved structural changes. Currently, space charge induced temporal broadening prevents obtaining high brightness electron pulses with sub-100 fs durations limiting the range of phenomena that can be studied with this technique. We review the state of the the art of UED in this respect and propose a practical design f...

In this paper, we propose a lossless (LS) image compression technique integrating a the integer wavelet transform with a prediction step that is a simplified version of the median edge detector algorithm used with JPEG-LS. First, the image is transformed using the prediction step and a difference image is obtained. The difference image goes through an integer wavelet transform and the transform...

The performance of Information Retrieval systems is a key issue in large web search engines. The use of inverted indexes and compression techniques is partially accountable for the current performance achievement of web search engines. In this paper, we introduce a new class of compression techniques for inverted indexes, the Adaptive Frame of Reference, that provides fast query response time, ...

Two major approaches have been proposed to efficiently process queries in databases: Speeding up the search by using index structures, and speeding up the search by operating on a compressed database, such as a signature file. Both approaches have their limitations: Indexing techniques are inefficient in extreme configurations, such as high-dimensional spaces, where even a simple scan may be ch...