Provided is an industrially applicable process for producing trans-4-hydroxy-L-proline, which is useful as a raw material for medicines or as an additive to foods. More particularly, it proposes a system and method for sending the ancillary data added to video data and the information inherent to the video data together with encoded streams in such a way that they will not be lost even if MPEG encoding and MPEG decoding are repeated. The information image managing server extracts user IDs of owners of the user information image and attribute information of copy information image data corresponding to those owners from an information image managing table.