Hi to all,


ever wondered how Dolby Digital 5.1 sound is ACTUALLY carried by a 35mm
cinema film ?

Turns out the 320 kbit/s DD data stream is encoded onto square, optical
grids of about 60 x 60 bits & very cunningly fitted in * between* the
sprocket holes !!

http://upload.wikimedia.org/wikipedi...udio_macro.jpg

The embedded Dolby logo is cute dontcha think ?

A tiny CCD camera in the projector captures each 2.4mm square image, 96 of
them per second, so it can be processed into 6 channels of audio.

The other tracks you see are Sony SDDS, L/R stereo analogue and timing
pulses for DTS so the CD can be synched with the movie.

Such a multi-format movie can be shown by any cinema in the world and exact
copies are made by ordinary, chemical film processing.

Betcha you ALL knew that already ....





........ Phil