04504860 is referenced by 29 patents and cites 7 patents.

A method and an apparatus for transmitting an image in which the image is sampled at a first plurality of points. The samples are then subjected to a two-dimensional unitary transform to produce a second plurality of transform coefficients, the second plurality being smaller than the first plurality and being obtained either by selection or truncation of the transform to provide the coefficients containing only the lower frequency components of the image. The transform coefficients are transmitted and on receipt converted by the inverse transform to a second plurality of image samples. Suitable transforms include the Hadamard and the discrete cosine. The image transmission is described as part of a viewdata system.

Title
Method and process for transmitting an image
Application Number
6/398608
Publication Number
4504860
Application Date
July 15, 1982
Publication Date
March 12, 1985
Inventor
King N Ngan
Singapore
SG
Roger J Clarke
Burton on the Wold
GB
Brian A Fenn
Woodbridge
GB
Richard C Nicol
Ipswich
GB
Agent
Mason Fenwick & Lawrence
Assignee
British Telecommunications
GB
IPC
H04N 7/12
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