GB1437429A - Generation of hadamard transforms of electrical signals - Google Patents

Generation of hadamard transforms of electrical signals

Info

Publication number
GB1437429A
GB1437429A GB3701073A GB3701073A GB1437429A GB 1437429 A GB1437429 A GB 1437429A GB 3701073 A GB3701073 A GB 3701073A GB 3701073 A GB3701073 A GB 3701073A GB 1437429 A GB1437429 A GB 1437429A
Authority
GB
United Kingdom
Prior art keywords
register
output
signals
elements
switch
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB3701073A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
British Broadcasting Corp
Original Assignee
British Broadcasting Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB3283771A external-priority patent/GB1366085A/en
Application filed by British Broadcasting Corp filed Critical British Broadcasting Corp
Priority to GB3701073A priority Critical patent/GB1437429A/en
Publication of GB1437429A publication Critical patent/GB1437429A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/60—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
    • G06F17/10—Complex mathematical operations
    • G06F17/14—Fourier, Walsh or analogous domain transformations, e.g. Laplace, Hilbert, Karhunen-Loeve, transforms
    • G06F17/145—Square transforms, e.g. Hadamard, Walsh, Haar, Hough, Slant transforms

Abstract

1437429 Data transmission; coding for facsimile systems BRITISH BROADCASTING CORP 7 June 1974 [3 Aug 1973] 37010/73 Addition to 1366085 Heading H4P In an arrangement as disclosed in parent Specification No. 1,366,085 in which a method and apparatus for generating a Hadamard transform of a series of 2<SP>N</SP> elements of an electrical signal is claimed and disclosed which includes N serial connected sections of order i where i takes once each of the values 1-N in any order, each section including first means for delaying the input by 2<SP>i-1</SP> elements and means for both adding and subtracting the delayed and undelayed signals, the apparatus is modified by halving a number of delay elements required. In the former apparatus only half the information stored is relevant to the transform the other half being rejected, hence in the present apparatus, by incorporating switching means, only relevant information is stored. The figure shows one of several serial stages for digital signals where the delay is conveniently a clocked 8 stage register connected at input and output to parts 12, 20 of a linked switch receiving on other inputs sum and difference of input signal 10 and delayed signals from 18. While the output of subtractor 16 is working its way through register 18, outputs of adder 14 are being applied through switch part 20 to output V. When the output of subtractor 16 reaches output of register 18, the switch 12, 20 reverses to apply signals emerging from register 18 to output V and incoming signals 10 are stepped through register 18. Switch 12, 20 then reverts for a further period of eight elements et seq. The improved arrangement uses all the register capacity all the time hence less apparatus is employed in the parent Specification. Different types of transforms may be obtained (a) by transposing the inputs of subtractor 16, (b) transposing 14 and 16 also (a) + (b) combined. These arrangements are particularly useful for asymmetrical transforms. Like the parent Specification, analogue signals may be processed by replacing the shift register by an appropriate clocked storage device, e.g. of capacitor type, together with analogue sum and difference circuits.
GB3701073A 1972-07-12 1973-08-03 Generation of hadamard transforms of electrical signals Expired GB1437429A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB3701073A GB1437429A (en) 1972-07-12 1973-08-03 Generation of hadamard transforms of electrical signals

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB3283771A GB1366085A (en) 1972-07-12 1972-07-12 Generation of hadamard transforms of electrical signals
GB3701073A GB1437429A (en) 1972-07-12 1973-08-03 Generation of hadamard transforms of electrical signals

Publications (1)

Publication Number Publication Date
GB1437429A true GB1437429A (en) 1976-05-26

Family

ID=26261584

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3701073A Expired GB1437429A (en) 1972-07-12 1973-08-03 Generation of hadamard transforms of electrical signals

Country Status (1)

Country Link
GB (1) GB1437429A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1035480A2 (en) * 1999-03-12 2000-09-13 Lucent Technologies Inc. Apparatus for performing a fast hadamard transform

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1035480A2 (en) * 1999-03-12 2000-09-13 Lucent Technologies Inc. Apparatus for performing a fast hadamard transform
EP1035480A3 (en) * 1999-03-12 2003-08-06 Lucent Technologies Inc. Apparatus for performing a fast hadamard transform

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Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee