| 摘要 |
PURPOSE:To efficiently retrieve a required picture at displaying speed requested by a user or in requested picture quality just like to turn over the page of a book even if the size of the restored picture is different. CONSTITUTION:A code data storage part 11 in which the code data of plural pictures with hierarchical structure is stored, a picture restoring part 13 to restore an original picture from the code data, and a code data supply control part 12 to control the supply of the code data from the code data storage part 11 to the picture restoring part 13 up to the number of hierarchies corresponding to the size of the picture restoring part 13 are provided. For instance, the number of gradations to be used for the restoration of the picture of standard size is set in the code data supply control part 12 as a reference value, and in the case that the size of the selected restored picture coincides with the reference size, the code data of the selected picture up to the standard number of the gradations is supplied, and in the case that it is different from the standard size, the code data up to the standard number of the gradations is supplied at the time of a picture quality priority mode, and the code data up to the number of the hierarchies of the product of the standard number of the gradations and the ratio of the reference size to the detected size is supplied at the time of a speed priority mode. |
