What are the current surround delivery formats for motion picture?
Dolby Digital, DTS, Sony Dynamic Digital Sound (SDDS) make up the majority of major motion picture releases today, with Dolby Surround fading away quickly. With Dolby Digital, the digitally encoded track is placed between the sprocket holes of the film in order to keep the analog optical tracks intact form playback in theaters without Dolby Digital decoding. With DTS, the encoded audio is stored on a CD-ROM which is synced to the film via special time code track placed between the optical track and the film frame. SDDS places the encoded digital signal outside the sprocket holes on both sides of the film. SDDS also utilizes a 7.1 format with center left and center right speakers added to the front array.
