Transmission of Vector Quantized Images by Self-Organizing Map Jari Kangas Helsinki University of Technology Neural Networks Research Centre Rakentajanaukio 2 C, FIN-02150, Espoo, FINLAND tel: +358 0 451 3275, fax: +358 0 451 3277 email: Jari.Kangas@hut. Abstract Image compression is needed for image storage and transmission applications. Vector quantization methods o er good performance when h...

In this paper, a rate-distortion function (RDF), R(D), is presented for a variable block-size classiication (VBSC) model. We obtain a theoretical R(D) bound on the performance of vector quantization (VQ) based on the VBSC model. It is theoretically proved that the R(D) bound of the VBSC model is lower than those of the Gaussian model and the xed block-size classiication (FBSC) model for the bit...

Several effective low bit rate still image compression methods have been presented in these two years, such as SPHIT [9], Hybrid VQ [7], Wu and Chen method [10]. These methods exercise the analysis techniques (wavelet or subband) before distributing the bit rate to each piece of image, thus the tradeoff between bit rate and distortion can be resolved. In this paper, we try to propose a simple b...

Vector Quantization (VQ) is a popular image compression technique with a simple decoding architecture and high compression ratio. Codebook designing is the most essential part in Vector Quantization. Linde–Buzo–Gray (LBG) is a traditional method of generation of VQ Codebook which results in lower PSNR value. A Codebook affects the quality of image compression, so the choice of an appropriate co...

Turfgrass growth, performance and quality are affected by abiotic stress factors and are of primary concern for persons managing turfgrass areas under seasonal tropical climates. Under these conditions, common Savannahgrass (SG) may have a performance advantage over imported hybrid turfgrasses. A greenhouse study was conducted to comparatively evaluate the performance of tropical turfgrasses ex...

A new kind of feature for colour image retrieval based on DCT-domain vector quantisation (VQ) index histograms (DCTVQIH) is proposed. For each colour image in the database, 12 histograms (four for each colour component) are calculated from 12 DCT-VQ index sequences, respectively. The retrieval simulation results show that, compared with the traditional spatial-domain colour-histogram-based feat...

| A variable dimension VQ (VDVQ) has code-words of unequal dimensions. Here a trellis-based sequential optimal VDVQ encoding algorithm is proposed. Also, a VDVQ codebook design algorithm based on splitting a node with equal or reduced dimensions is proposed, that does not require any codebook parameter to be pre-speciied unlike known schemes. The VDVQ system is shown to outperform a few known V...

BACKGROUND Changes in pulmonary deadspace are indicators of disease status (e.g. pulmonary embolus, acute respiratory distress syndrome) and they have prognostic usefulness in the intensive care unit. The components of pulmonary deadspace, the alveolar and anatomical deadspaces (VDalv and VDanat), are commonly considered to be independent (i.e. the addition of airway equipment should not alter ...

We report a three-phase bone scintigraphy for the diagnosis of a peripheral bone lesion caused by systemic sarcoidosis. A 32-year-old man with suspected osteomyelitis of the right forefinger underwent three-phase bone scintigraphy with Tc-99m hydroxymethylene diphosphonate (HMDP) and single-photon emission computed tomography/computed tomography (SPECT/CT). The lesion was rich in blood flow acc...