METHOD FOR INSERTING/EXTRACTING ADDITIONAL INFORMATION TO/FROM MP3 FILE

摘要

PURPOSE: A method for inserting/extracting additional information to/from an MP3 file is provided to directly insert/extract additional information data to/from a compressed audio signal, and to insert/extract the data without releasing a compressed file. CONSTITUTION: A system prepares for additional information data to be inserted(S302). The system divides a scale factor area for inserting the additional information data into sub areas(S304). The system conducts modular N arithmetic for each sub area(S306). The system compares modular N arithmetic results, and determines one bit for each sub area(S308). The system compares the determined bit with an equivalent bit of the additional information data to be inserted(S310). If the compared values are the same, the system decides whether all the additional information data are inserted(S314). If so, the system completes the procedure.