Um Novo Algoritmo para Atribuição de Índices: Avaliação em Quantização Vetorial de Imagens
DOI:
https://doi.org/10.5540/tema.2009.010.02.0167Abstract
A quantização vetorial (QV) tem sido amplamente utilizada em sistemas de codificação de imagens, permitindo a obtenção de taxas de compressão elevadas. No entanto, a QV é muito sensível a erros de canal, que podem levar a bloqueamentos espúrios muito incômodos nas imagens reconstruídas. No presente trabalho, é apresentado um novo método de atribuição de índices aos vetores-código, baseado em otimização discreta no espaço das permutações, visando tornar a QV mais robusta aos erros de canal.References
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