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1. EP0770246 - METHOD AND APPARATUS FOR COMPRESSING IMAGES

Office European Patent Office
Application Number 95926684
Application Date 14.07.1995
Publication Number 0770246
Publication Date 02.05.1997
Publication Kind A4
IPC
H04N 1/41
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
1Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
41Bandwidth or redundancy reduction
G06T 9/00
GPHYSICS
06COMPUTING; CALCULATING OR COUNTING
TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
9Image coding
H04N 7/26
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
7Television systems
24Systems for the transmission of television signals using pulse code modulation
26using bandwidth reduction
H04N 7/30
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
7Television systems
24Systems for the transmission of television signals using pulse code modulation
26using bandwidth reduction
30involving transform coding
H04N 19/94
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
19Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
90using coding techniques not provided for in groups H04N19/10-H04N19/85103
94Vector quantisation
CPC
H04N 19/124
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
19Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
10using adaptive coding
102characterised by the element, parameter or selection affected or controlled by the adaptive coding
124Quantisation
H04N 19/126
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
19Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
10using adaptive coding
102characterised by the element, parameter or selection affected or controlled by the adaptive coding
124Quantisation
126Details of normalisation or weighting functions, e.g. normalisation matrices or variable uniform quantisers
H04N 19/186
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
19Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
10using adaptive coding
169characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding
186the unit being a colour or a chrominance component
H04N 19/30
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
19Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
30using hierarchical techniques, e.g. scalability
H04N 19/60
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
19Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
60using transform coding
H04N 19/63
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
NPICTORIAL COMMUNICATION, e.g. TELEVISION
19Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
60using transform coding
63using sub-band based transform, e.g. wavelets
Applicants JOHNSON GRACE COMPANY
Inventors JOHNSON STEPHEN G
Designated States
Priority Data 27616194 14.07.1994 US
9508827 14.07.1995 US
Title
(DE) VERFAHREN UND GERÄT ZUR BILDKOMPRESSION
(EN) METHOD AND APPARATUS FOR COMPRESSING IMAGES
(FR) PROCEDE ET APPAREIL POUR COMPRIMER DES IMAGES
Abstract
(EN)
A system and method is disclosed that compresses and decompresses images. The compression system and method (126, 128, 130, 132) includes an encoder (130) which compresses images and stores such compressed images in a unique file format, and a decoder (110) which decompresses images. The encoder (130) optimizes the encoding process to accommodate different image types with fuzzy logic methods (152) that automatically analyze and decompose a source image, classify its components, select the optimal compression method for each component, and determine the optimal parameters of the selected compression methods. The encoding methods inlcude: a Reed Spline Filter (138), a discrete cosine transform (136), a differential pulse code modulator (140), and enhancement analyzer (144), an adaptive vector quantizer (134) and a channel encoder (132) to generate a plurality of data segments that contain the compressed image. The plurality of data segments are layered in the compressed file (104) to optimize the decoding process. The first layer allows the decoder (110) to display the compressed image as a miniature or a coarse quality full sized image, the decoder (110) then adds additional detail and sharpness to the displayed image as each new layer is received. The decoder (110) uses optimal decompression methods to expand the compressed image file.

(FR)
L'invention concerne un système et un procédé pour comprimer et décomprimer des images. Ce système et ce procédé de compression (126, 128, 130, 132) utilisent un codeur (130) qui comprime les images et les mémorise, une fois comprimées, dans un format de fichier unique. Il comprend, en outre, un décodeur (110) qui décomprime les images. Le codeur (130) optimise le processus de codage pour adapter différents types d'images à des procédés logiques flous (152) qui analysent et décomposent automatiquement une image source, classent ses composantes, sélectionnent le procédé de compression optimal pour chaque composante et déterminent les paramètres optimaux des procédés de compression sélectionnés. Les procédés de codage utilisent un filtre à lame vibrante (138), une transformée de cosinus discrète (136), un modulateur de code d'impulsions différentielles (140) et un analyseur d'enrichissement (144), un quantificateur de vecteur adaptatif (134) et un codeur de canal (132) pour générer une pluralité de segments de données contenant l'image comprimée. Ces segments de données sont organisés en couches dans le fichier comprimé (104) pour optimiser le processus de décodage. La première couche permet au décodeur (110) de visualiser l'image comprimée sous forme d'une miniature ou d'une image grandeur nature de qualité primaire. Le décodeur (110) ajoute ensuite d'autres détails et plus de précision à l'image visualisée lors de la réception de chaque couche. Le décodeur (110) utilise les procédés de décompression optimaux pour développer le fichier d'images comprimées.