Strong edge features for image coding

A two-component model is proposed for perceptual image coding. For the first component of the model, the watershed operator is used to detect strong edge features. Then, an efficient morphological interpolation algorithm reconstructs the smooth areas of the image from the extracted edge information, also known as sketch data. The residual component, containing fine textures, is separately coded by a subband coding scheme. The morphological operators involved in the coding of the primary component perform very efficiently compared to conventional techniques like the LGO operator, used for the edge extraction, or the diffusion filters, iteratively applied for the interpolation of smooth areas in previously reported sketch-based coding schemes.Peer ReviewedPostprint (published version

A feature-based subband coding scheme

A feature-based subband coding scheme is presented. It is intended for the coding of the texture component of a two-component image model. The primary component contains the strong edges, individually described by their amplitudes and positions. A morphological interpolation technique, presented by Casas, Salembier and Torres (see IEEE International Conference on Image Processing, vol.I, p.526-9, 1995), reconstructs the smooth areas of the image from the coded transitions. The residual texture component is coded by subband decomposition. Information about the edge structure, available from the primary component, is used for texture coding by employing adaptive quantizers and bit allocations over arbitrarily shaped regions. This feature-based subband coding technique produces subjective improvements over conventional subband schemes. The enhanced rendition of the strong edges is especially noticeable at very-low bit-rates. The coding of the primary component, based on morphological tools, is also more efficient and of lower complexity than in previously reported schemes for two-component image coding modelsPeer ReviewedPostprint (published version

A feature-based subband coding scheme

A feature-based subband coding scheme is presented. It is intended for the coding of the texture component of a two-component image model. The primary component contains the strong edges, individually described by their amplitudes and positions. A morphological interpolation technique, presented by Casas, Salembier and Torres (see IEEE International Conference on Image Processing, vol.I, p.526-9, 1995), reconstructs the smooth areas of the image from the coded transitions. The residual texture component is coded by subband decomposition. Information about the edge structure, available from the primary component, is used for texture coding by employing adaptive quantizers and bit allocations over arbitrarily shaped regions. This feature-based subband coding technique produces subjective improvements over conventional subband schemes. The enhanced rendition of the strong edges is especially noticeable at very-low bit-rates. The coding of the primary component, based on morphological tools, is also more efficient and of lower complexity than in previously reported schemes for two-component image coding modelsPeer Reviewe