Patent ID: 6804404
Filing Date: 2004-10-12
Classification: G06T

Abstract:
A shape information coder for coding shape information represented by a set of pixels, the shape information relating to a particular image, the shape information coder comprising:first resolution converting means dividing said set of pixels into a plurality of mutually exclusive first-resolution subsets, each first-resolution subset among said plurality of first-resolution subsets representing a different subsampling of said shape information and having a first resolution lower than a resolution of said shape information; first memory means coupled to said first resolution converter, storing said first-resolution subsets; first context generating means coupled to said first memory means, selecting reference pixels from said first memory means for each pixel in said first-resolution subsets, except in one of said first-resolution subsets, and generating context information for each said pixel from the reference pixels selected therefor; second resolution converting means dividing said one of said plurality of first-resolution subsets into a plurality of mutually-exclusive second-resolution subsets, each second-resolution subset among said plurality of second-resolution subsets representing a different subsampling of said one of said plurality of first-resolution subsets and having a second resolution lower than said first resolution; second memory means coupled to said second resolution converter, storing said second-resolution subsets; second context generating means coupled to said second memory means, selecting reference pixels from said second memory means for each pixel in said second-resolution subsets, and generating context information for each said pixel from the reference pixels selected therefor; and coding means coupled to said context generating means, coding each said second-resolution subset and each said first-resolution subset other than said one of said plurality of first-resolution subsets according to the context information of the pixels in said first-resolution subset, and coding each said second-resolution subset according to the context information of the pixels in said second-resolution subset.