| 摘要 |
<p>PURPOSE:To shorten the time required for a retrieval by providing write side and read-out side memories which are operated independently, on a code memory, decoding and displaying an approximate picture of a detailed picture at a high speed, and deciding by the approximate picture whether the relieval is correct or erroneous. CONSTITUTION:A code memory 22 of an encoding device 15 is provided with a write side memory 22-2 and a read-out side memory 22-1 which are operated independently. In case of decoding, first of all, when a code of the third layer being a basic code is inputted successively to an operating part 21, it is stored in a frame buffer 24 through the memory 22-2. Subsequently, a display device 16 reads out the contents of the buffer 24, a picture of the third layer is displayed, and when a partial area is indicated through an indicating device 17, the next decoding is executed. In this state, the read-out side and the write side of the memory 22 are shifted, said picture is inputted to the operating part 21 successively together with differential information from the center, and synthesized, and an approximate picture of a detailed picture is decoded and displayed at a high speed. By deciding by this approximate picture whether the retrieval is correct of erroneous, the time required for the retrieval can be shortened.</p> |
