| 摘要 |
<p>PURPOSE:To improve significantly the efficiency of encoding and the stability of synchronism by changing a code length in accordance with the generating frequency of a DPCM code and forming a variable length code in transmitting and receiving data to a self-synchronizing type code. CONSTITUTION:At a transmitting device 1, a differential quantizing part 4 differentially quantizes the PCM codes of an image and converts it from this to the DPCM code of a short code length. A variable length code encoding part 9 converts the DPCM code to a self-synchronizing type variable length code where the more a generating frequency is, the shorter a code length is and only one bit inversion in the prescribed direction exists on the way of the code. A serial converting part 11 continuously serially converts the variable length code and forms and outputs the bit serial transmitting data. At a receiving device 2, a parallel converting part 14 detects the reverse bit inversion in the prescribed direction of the receiving data, identifies the starting edge of the variable length code and converts the receiving data in parallel by a variable length code unit. A variable length code decoding part 15 changes the output data to the DPCM code, decodes the variable length code and a DPCM code decoding part 17 decodes and outputs the DPCM code.</p> |
