Picture-in-picture the screen. Televisions at the time were still analog format, and earlier versions of the PiP implemented in analog were too costly. New digital technology allowed the second video signal to be digitized and saved in a digital memory chip then replayed in a mini version. While the new technology was not good enough for color or full-screen viewing, it did provide a low-cost PiP feature. The Blu-ray Disc and HD DVD specifications included picture in picture, allowing viewers to see, say, the director's comment on a film they are watching. All of the Blu-ray Disc titles in 2006 and
Compressed audio optical disc Compressed audio optical disc A compressed audio optical disc, MP3 CD, or MP3 CD-ROM or MP3 DVD is an optical disc (usually a CD-R, CD-RW, DVD-R or DVD-RW) that contains digital audio in the MP3 file format. Discs are written in the "Yellow Book" standard data format (used for CD-ROMs and DVD-ROMs), as opposed to the Red Book standard audio format (used for CD-DA audio CDs). Compressed audio files are supported by many modern CD players as well as DVD players. Disc players are capable of playing compressed formats, such as MP3, the most commonly used format, as well as