| 摘要 |
electric communications; compression of digital messages for their transmission and storage. SUBSTANCE: method used for compressing digital messages such as voice, sound, television, facsimile, and the like messages to facilitate their transmission and storage involves pre-shaping approximating sequences to be coded, coding them, determining and comparing length of each approximating coded sequence with preset maximum permissible length, erasing approximating sequences to be coded for which lengths of respective approximating coded sequence is greater than maximum permissible length, selecting one of approximating sequences to be coded closest to sequence to be coded, and taking it as coded sequence of binary characters. Device implementing this method has identifying unit, statistical parameter computing unit, first and second normalizing units, first, second, and third normalizing shift registers, subtracter, comparator, first, second, and third switching units, adder, first and second coding-parameter storage units, code interval register, first and second left-hand shift registers, lower coding boundary register, as well as newly introduced unit for sequence to be coded, memory unit for approximating sequences to be coded, switch, selection unit, memory unit for approximating coded sequences, comparison unit, and maximum length memory unit. EFFECT: reduced time of coded data transmission over communication channel; reduced memory capacity required for coded sequence storage device. 10 cl, 27 dwg
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