| 摘要 |
<p>PURPOSE:To attain encoding with one reciprocating scanning by providing a decentralizing processing means applying decentralizing processing based on the scanning of an original at a forward motion and coding processing means applying encoding based on the original scanning at return. CONSTITUTION:A switch 5 selects a decentralizing processing section 6 at a forward path of a scanning optical system 30 to execute the decentralizing processing, the decentralizing processing section 6 generates a bit assignment table based on the result of decentralizing processing and the result is stored in a bit assignment table storage section 8. A switch 9 is thrown to the position of a transmission line 10 and the content of a bit assignment table of the bit assignment table storage section 8 is sent to a transmission line 10 as header information. On the other hand, the switches 5, 9 select a quantization section 7 in the return path of the scanning optical system 30, a data is read and a 2-dimension DCT conversion section 3 applies 2-dimension DCT conversion to apply NXN coefficient from an NXN buffer 4 and a bit assignment table read from the bit assignment table storage section 8 to the quantization section 7, in which the quantizing processing is executed. Thus, encoding is attained by reciprocating the original scanning once.</p> |
