PICTURE ENCODING DEVICE

摘要

PURPOSE:To efficiently encode in a natural picture and to obtain a large compression ratio by comparing a change in a picture signal with an evaluation function decremented monotonously. CONSTITUTION:An input picture signal 1 is sampled and quantized at an AD converter 3 by using a sampling clock F32 and becomes digital data S0, S1-Si- and latched by a register 5. Then a subtractor 6 calculates differences S1-S0, S2-S0. The differences are fed to a comparator 9 via an absolute value circuit 7. On the other hand, an output of a counter 4 counting a clock FS is given to a ROM 8 as an address. The ROM 8 outputs monotonously decreasing evaluation functions D1, D2-Di- stored in advance and gives them to the comparator 9. The comparator 9 compares them sequentially and when the difference S1-S0 reaches the function Di or over, the comparator 9 generates an output. Thus, the Si and Di are stored in a buffer memory 10. The memory 10 formats them and outputs the result.