Waveform coding system

Abstract

Abstract PURPOSE:To cover a range of all input PCMs, by transmitting selectively the compressed PCM signals of the same number of bits when the maximum effective bit of the differential data between adjacent signals exceeds the expected level. CONSTITUTION:An effective maximum level signal is fed to a data compressing circuit 18 from an adaptive level setting circuit 16. Then the circuit 18 feeds compressed PCM signals ranging from an upper bit to the effective minimum level like a differential data compressing circuit 15 to a terminal A of a data selecting circuit 19. Therefore levels 3-0 are detected by the circuit 16, and a level detecting circuit 17 to which the effective minimum level signal is fed delivers ''0'' to the circuit 19 for selection of a terminal B and then delivers ''1'' to the circuit 19 for selection of the terminal A when receiving level 4 respectively. Thus the levels 3-0 are turned into ADPCMs as before. However, an output signal is not turned into a differential data signal but into a compressed PCM signal with level 4.

Inventors

• 👤 Toshihiro Hoshi
• 👤 星　敏弘
• 👤 Shigeru Takagi
• 👤 茂 高木

Bibliographic Details