Clover Systems DVX-4, Руководство по эксплуатации

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DVX Instruction Manual 57
GLOSSARY
ATime ( Absolute Time) Timecode encoded in the subchannel of a CD in the form of playing time at 1X in
minutes, seconds, and frames from beginning of the program area.
ATIP ( Absolute Time In Pregroove) Samde as ATime but encoded in the pregroove and used by a writer to
locate position on an unrecorded disc.
BLER (BLock Error Rate) The total number of errors encountered at the C1 stage (=E11 + E21 +
E31)
CAV ( Constant Angular Velocity) The disc rotates at a fixed RPM. This results in a variable data rate, as
the discs are recorded with CLV. Data rate is higher at the outside of the disc.
CD-DA ( CD-Digital Audio) Audio disc using 16 bit linear streaming data to represent each digital sample of
two audio channels. CD-DA discs do not have sectors.
CD-R ( CD-Recordable) W rite once-read many disc specified by the Orange Book Part II. It uses a molded
in pre-groove to guide the laser during recording. The laser makes marks in the dye polymer layer by
heating.
CD-ROM ( CD-Read Only Memory) Data discs made according to the Philips/Sony Yellow Book. This term is
often used to signify a molded disc as opposed to a CD-R disc.
CD-ROM XA ( CD-ROM eXtended Architecture) A data disc that includes a subheader to support various modes of
interleaving audio, graphics, video and computer data using CD- ROM XA Mode 2/Form 1 and CD-
ROM XA Mode 2/Form 2 sectors. Error correction capability depends on the mode and form of the
data.
CD-RW ( CD-ReWritable) Re-Writable disc made according to Orange Book Part III that can be recorded,
erased, or overwritten. Uses a pre-groove like CD-R, but recording mechanism is phase change. Heat
from the laser changes the medium from crystalline to amorphous structure, which has lower
reflectivity. CD-RW reflectivity is much lower than CD-R, so not all drives can read these discs.
CIRC ( Cross Interleave Reed-Solomon Code) A method of error detection and correction employing parity
bytes together with interleaving. Interleaving distributes the data over a relatively large area of the
disc, so that one large defect becomes many small defects after de-interleaving. C1 is the first stage
of error correction, followed by de-interleave and C2 the correction stage.
CLV ( Constant Linear Velocity) The scanning speed of the laser over the pits is constant. All CDs and
DVDs are formatted this way. This requires higher rotational speed at the inside of the disc, and
lower speed at the outer tracks. This produces a constant data rate.
DAO ( D isc A t O nce) Recording method where the entire disc contents are recorded in one continuous
operation. Molded discs are always recorded using this method.
E11 One bad byte in a data frame at the C1 stage, which was corrected (CD Only).
E21 Two bad bytes in a data frame at the C1 stage, which were corrected (CD Only).
E31 Three or more bad bytes in a data frame at the C1 stage, which were not corrected (CD Only).
E12 One bad byte in a data frame at the C2 stage, which was corrected (CD Only).
E22 Two bad bytes in a data frame at the C2 stage, which were corrected (CD Only).
E32 Three or more bad bytes in a data frame at the C2 stage, which were not corrected (CD Only).
EDC / ECC ( Error Detection Code / Error Correction Code ) Additional error correction data that is added to
data CDs, providing an additional layer of error correction in addition to CIRC.
ECC Block On a DVD disc, this refers to one Reed-Solomon Product code error correction block. 1 ECC block =
16 sectors = 32768 user bytes.
EFM ( Eight-to-Fourteen Modulation) Modulation scheme used by CDs; converts eight data bits to
fourteen channel bits prior to recording.