US 8,285,063 B2 · Multi-mode vector-based image processing

Abstract

A block (300) of image elements (310) is compressed by identifying a base vector (460) based on normalized feature vectors (312) of the block (300). If a position-determining coordinate (420) of the base vector (460) is present inside a defined selection section (530) of feature vector space (500), the block (300) is compressed according to a default mode and an auxiliary mode to get a default and auxiliary compressed block (600), respectively. The compressed block (600) resulting in smallest compression error is selected. If the auxiliary mode is selected, the position-determining coordinate (420) is mapped to get a mapped coordinate (425) present outside the representable normalization portion (510) of vector space (500). The auxiliary compressed block (600) comprises a representation of this mapped coordinate (425). If the default mode is selected no such coordinate mapping is performed and the default compressed block (600) instead comprises a representation of the non-mirrored coordinate (420).

Claims24

Dependent claims

A method of compressing a block of image elements, each image element having an associated normalized feature vector present in a normalization sub-region of a vector feature space, said method comprising the steps of:

identifying, based on at least a portion of said normalized feature vectors, a base vector in said normalization sub-region;
coding, if a position-determining coordinate of said base vector is present in a defined selection section of said feature vector space, at least one image element of said block according to a default compression mode and an auxiliary compression mode;
selecting the compression mode of said default compression mode and said auxiliary compression mode based on a default compression mode error and an auxiliary compression mode error;
and
mapping, if said selected compression mode is said auxiliary compression mode, said position-determining coordinate to get a mapped position-determining coordinate present in a mapped selection section positioned outside of said normalization sub-region, wherein a compressed representation of said block comprises a representation of said mapped position-determining coordinate if said selected compression mode is said auxiliary compression mode and a representation of said position-determining coordinate if said selected compression mode is said default compression mode.

2 more elements

A method of decoding a normalized feature vector representing an image feature of an image element from a compressed block, said method comprising the steps of:

identifying whether a first codeword of said compressed block represents a first position-determining coordinate present outside of a normalization sub-region of feature vector space;
mapping, if said first position-determining coordinate is present outside of said normalization sub-region, said first position-determining coordinate to get a first mapped position-determining coordinate present in said normalization sub-region;
decoding said compressed block according to an auxiliary decoding mode based on said first mapped position-determining coordinate to get a normalized representation vector as decoded representation of said normalized feature vector.

A compressor for compressing a block of image elements, each image element having an associated normalized feature vector present in a normalization sub-region of vector feature space, said compressor comprising:

an identifier for identifying, based on at least a portion of said normalized feature vectors, a base vector in said normalization sub-region;
an encoder for coding, if a position-determining coordinate of said base vector is present in a defined selection section of said feature vector space, at least one image element of said block according to a default compression mode and an auxiliary mode;
a mode selector for selecting the compression mode of said default compression mode and said auxiliary compression mode based on a default compression mode error and an auxiliary compression mode error;
and
a mapping means for mapping, if said mode selector selects said auxiliary compression mode as selected compression mode, said position-determining coordinate to get a mapped position-determining coordinate present in a mapped selection section positioned outside of said normalization sub-region, wherein a compressed representation of said block comprises a representation of said mapped position-determining coordinate if said selected compression mode is said auxiliary compression mode and a representation of said position-determining coordinate if said selected compression mode is said, default compression mod.

2 more elements

A decoder for decoding a normalized feature vector representing an image feature of an image element from a compressed block, said decoder comprising:

a coordinate identifier for identifying whether a first codeword of said compressed block represents a first position-determining coordinate present outside of a normalization sub-region of feature vector space;
a mapping means for mirroring, if said first position-determining coordinate is present outside of said normalization sub-region, said first position-determining coordinate to get a first mapped position-determining coordinate present in said normalization sub-region;
an auxiliary mode decoder for decoding said compressed block according to an auxiliary decoding mode based on said first mapped position-determining coordinate to get a normalized representation vector as decoded representation of said normalized feature vector.

Dependencies are inferred from the claim text.

Multi-mode vector-based image processing

Life of this patent

Multi-mode vector-based image processing

Life of this patent

Abstract

Claims24