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questo :
The standard home video LaserDisc was 11.81 in (30 cm) in diameter and made up of two single-sided aluminum discs layered in plastic. Although appearing similar to compact discs or DVDs, LaserDiscs used analog video stored in the composite domain (having a video bandwidth approximately equivalent to the 1-inch C-Type VTR format) with analog FM stereo sound and some form of digital audio [what form?]. However, despite its analog nature, the LaserDisc at its most fundamental level was still recorded as a series of pits and lands much like CDs, DVDs, and even Blu-ray Discs are today. Note however that although the encoding is of a binary nature, that does not make it digital since the information is encoded as analog pulse width modulation with a 50% duty cycle, with the information contained in the lengths and spacing of the pits. This is unlike digital media where the pits, or their edges, directly represent 1's and 0's.[14] The spiral track of a LaserDisc is
42 miles (67 km) long. Early LaserDiscs featured in 1978 were entirely analog but the format evolved to incorporate digital stereo sound in CD format (sometimes with a TOSlink or coax output to feed an external DAC), and later multi-channel formats such as Dolby Digital and DTS.
dove si capisce chiaramente che sul disco i dati sono di natura "binaria" ovvero ,il laser legge solo degli 0 o degli 1.
come parola a N bit. solo per questo fatto si dice che il laserdisc
a questo punto abbinare il dato memorizzato nel laserdisc a quello di un LP o di una cassetta ,mi sembra alquanto errato, visto che nel primo ,la traccia nel vinile, ha la forma del suono in entrata (con correzione RIAA) mentre nel secondo la traccia ha il campo magnetico proporzionale all'ampiezza del audio.