ENCODER FOR CONTENTS DATA, RECORDING MEDIUM, DISTRIBUTION METHOD AND USER TERMINAL

摘要

PROBLEM TO BE SOLVED: To prevent a scramble code from being recognized in the absence of audio data in a distribution system of contents data including the audio data. SOLUTION: An encoder 43A detects a non-voice period of audio data for each partial pack length of one pack length of the audio data and the audio data are scrambled for a voiced period by using an EX-OR circuit 2 that exclusively ORs the audio data with a PN code generated on the basis of a memory device ID and an output signal of a through-path is selected for a non-voice period or a period close thereto. Furthermore, a reproduction side applies a prescribed OR between the scrambled audio data with a scramble code to descramble the audio data for a voiced period and an output signal of the through-path is selected for a non-voice period.