| 摘要 |
PURPOSE:To make it possible to change coding characteristics over without transmitting change-over information, by integrating the volume of codes by setting the initial value of coded information volume integration by using the occupation volume of a buffer memory and by changing coding characteristics over on the basis of the integrated value. CONSTITUTION:As for an A/D-converted color TV signal, quantization characteristics of quantizer 202 are changed over with the mode signal of controller 206 and its output is coded by variable-length coder 205 and stored in buffer memory 207. In this case, controller 206 receives a memory occupation-volume signal in every interval from memory 207 to set the initial value of coded information volume integration and then uses the integral value of a code-length signal from coder 205 to change-over coding characteristics of quantizer 202. To memory 207, the initial value of information volume integration in every interval and a head value signal in every interval are added and sent out to a transmission line. At the reception side, the input is stored in buffer memory 208 and then controller 210 finds an integrated value from the initial value to change-over coding characteristics of variable-length decoder 209, thereby outputting a PCMTV signal via forecasting decoder 215 of high degree. |
