| 摘要 |
The present invention provides a system in which audio files are distributed that include watermarks, digital signatures and/or encryption. The file may offer content owners some amount of playback control, while offering the consumer value-added content & services, and maintaining backward compatibility to existing digital file players such as MP3 players. By enticing the consumer with value-added content and services alongside the purchased songs, the consumer is encouraged to obtain these files from participating retailers and to replay the files using compliant players. |
