US 5,630,115 A · Method of rewriting information on a record medium by rewriting only changed portions

Abstract

In a method of rewriting a file data recorded on a record medium such as an optical memory card in successive tracks each constituting a minimum unit record, the file data is read out of the optical memory card as old records of an old file, the thus read out respective records of the old file are compared with corresponding records of a new file formed on a main memory disk to detect a revised record, and only the thus detected revised record is recorded on the record medium. On the main memory disk, there is further formed recording position information denoting a position on the record medium at which said revised record has been recorded and the thus formed recording position information is recorded on the record medium together with old and new file names. Only the revised record is recorded on the record medium, so that its data record area can be utilized optimally.

Claims22

Dependent claims

A method of rewriting information recorded on a record medium, said method comprising:

reading out of said record medium old file contents onto which new file contents are to be written;
detecting a difference between said old file contents and said new file contents to determine a portion of the new file contents which is different from a corresponding portion of said old file contents;
forming management information for denoting a fact that said portion of the old file contents is to be rewritten by said portion of the new file contents, said management information comprising recording position information which denotes a position on said record medium at which said portion of said new file contents is to be written;
recording said portion of the new file contents as well as said management information on said record medium, said recording position information being recorded in a vacant track in a data record section in the record medium;
and
recording, in a vacant region in a directory record section in said record medium, a position of said vacant track in which said recording position information has been recorded.

3 more elements

Dependencies are inferred from the claim text.

Method of rewriting information on a record medium by rewriting only changed portions

Life of this patent

Method of rewriting information on a record medium by rewriting only changed portions

Life of this patent

Abstract

Claims22