Alexandre Zaghetto

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— H.264/AVC is the newest, state-of-the-art, video compression standard. Recently adopted, it leads to substantial performance improvement compared to other existing standards. In this paper we want to explore less known features of the H.264/AVC that were not the main intent of the standard. We begin by showing a few comparisons as examples of how the(More)
In this paper, we explore H.264/AVC operating in intraframe mode to compress a mixed image, i.e., composed of text, graphics, and pictures. Even though mixed contents (compound) documents usually require the use of multiple compressors, we apply a single compressor for both text and pictures. For that, distortion is taken into account differently between(More)
The mixed raster content (MRC) document compression standard (ITU T.44) specifies a multi-layer multi-resolution representation of a compound document. The model is very efficient for representing sharp text and graphics onto a background. However, since the mask layer is binary, it is difficult to deal with scanned data and soft edges. The edge transitions(More)
The emerging video coding standard, HEVC, was developed to replace the current standard, H.264/AVC. However, in order to promote inter-operability with existing systems using the H.264/AVC, transcoding from H.264/AVC to the HEVC codec is highly needed. This paper presents a transcoding solution that uses machine learning techniques in order to map H.264/AVC(More)
The Mixed Raster Content (MRC) ITU document compression standard (T.44) specifies a multi-layer representation of a compound document. It is expected that higher compression can be achieved if more efficient compression standards are used to compress each layer. In this paper we present an MRC compound document codec that uses H.264/AVC operating in INTRA(More)
We present a new preprocessing technique for two-dimensional compression of surface electromyographic (S-EMG) signals, based on correlation sorting. We show that the JPEG2000 coding system (originally designed for compression of still images) and the H.264/AVC encoder (video compression algorithm operating in intraframe mode) can be used for compression of(More)
This paper proposes a hybrid pattern matching/transform-based compression method for scanned documents. The idea is to use regular video interframe prediction as a pattern matching algorithm that can be applied to document coding. We show that this interpretation may generate residual data that can be efficiently compressed by a transform-based encoder. The(More)
This article presents an algorithm for compression of echocardiographic images. The algorithm is based on the JPEG algorithm and uses a fuzzy inference system to adapt the normalization process of the transformed coefficients through the analysis of the local characteristics of echocardiographic images. The images considered in this paper were acquired in(More)
This paper proposes a hybrid approximate pattern matching/transform-based compression engine. The idea is to use regular video interframe prediction as a pattern matching algorithm that can be applied to document coding. We show that this interpretation may generate residual data that can be efficiently compressed by a transform-based encoder. The novelty(More)