Blue Book (CD standard) Blue Book (CD standard) The Blue Book is a compact disc standard developed in 1995 by Philips and Sony. It defines the Enhanced Music CD format (E-CD, also known as CD-Extra, CD-Plus and CD+), which combines audio tracks and data tracks on the same disc. The format was created as a way to solve the problem of mixed mode CDs, which were not properly supported by many CD players. The standard is not freely available and must be licensed from Philips. E-CDs are created through the "stamped multisession" technology, which creates two sessions on a disc. The first session of
WARP-CD on channel 20. The station, previously WARP-CA, began broadcasting a digital-only signal in late 2009. WARP-CA's call sign suffix (CA for Class A Low Power) was changed to WARP-CD (Class A Digital) automatically upon grant of WARP-CA's digital license in late 2009. WARP-CD currently broadcasts four channels of standard definition digital TV: 20.1, 20.2, 20.3 and 20.4. Longtime owner Randolph Weigner (who controls Sunshine Broadcasting Company) sold WARP, along with sister station WPHA-CD in Philadelphia, to LocusPoint Networks in November 2012. The deal made WARP a sister station to WSVT-LD, which LocusPoint acquired a month later. WARP-CD WARP-CD is a