IMAGE TRANSMISSION SYSTEM

摘要

PURPOSE:To make edge business hard to occur and to obtain high compressibility and high picture quality by making range of quantized values which differ in sampling interval to overlap with each other, and providing a variable density encoding process wherein encoding is performed in constant relation corresponding to the combination of the quantized values and sampling intervals. CONSTITUTION:This example circuit corresponding to a variable sample density encoding circuit consists of a quantizing circuit 24 and a quantization characteristic table 25 in which quantization characteristics are written. Further, a variable sample density decoding circuit 16b consists of an interpolating circuit 26 which interpolates and restores a forecasted error decoded signal on the basis of a time difference value and an amplitude difference value from the quantizing circuit 26. A constant interval is added by a sampling circuit when the amplitude difference value is less than the constant value and encoding into a code determined by the combination of the time difference value and amplitude difference value is so performed that the amplitude difference value quantized when a forecasted error signal (c) for the time difference value is quantized into the amplitude difference value by the quantizing circuit 24 can select any of values smaller than the constant value; and quantization level overlap with each other possibly.