Time Code Functions - evertz 4025TR Instruction Manual

3.9 TIME CODE FUNCTIONS

OPERATION
The 4025TR Film Footage Encoder contains a multi-line vertical interval
(VITC) and a linear (LTC) time code generator.
operated in local mode, the primary VITC generator follows the LTC
generator, except that it is updated at the field rate instead of the frame
rate. The secondary VITC generator is used to encode the full KeyKode
edge number including frames in certain modes.
supports encoding the data in VITC according to the 3-line VITC standard
Evertz has developed with other manufacturers. Both the VITC 2 line of
the two line format and the second and third line of the three line format
have special encoding applied such that they require a special Evertz
reader such as the Afterburner to decode the data. With this special
encoding applied, conventional readers will not become confused by the
special film numbering systems required to encode the data. Figure 3-10
shows the various ways that the 4025TR will encode time and KeyKode
numbers, showing what data is placed in each set of VITC lines. Figure 3-
11 shows how the data is encoded in the 3-line standard.
4025TR is controlled from the KeyLog TRACKER™ graphical user
interface, the LTC and VITC generators can be controlled independently.
The 4025TR has two logical timecode generators - Video time code, Audio
time code. The Video and Audio time code logical generators can be
driven from either the LTC or VITC readers, or from the telecine biphase.
In addition an internal clock that the operator can start and stop can drive
the Video time. When the timecodes are not slaved to one of the readers
they can be preset from the front panel. When they are slaved to one of
the readers an optional offset between the reader and generator can be
applied.
The 4025TR also has two logical film number generators – Film edge
numbers (Keykode) and Ink numbers. The film number generators are
driven by the telecine biphase and update at the film transfer rate,
accurately tracking the 2/3 pulldown in NTSC 24 frame per second
transfers. Because the LTC is only a frame rate code, the film edge
numbers in the user bits are only accurate to the closest frame in the LTC
output. The VITC output is field accurate when the LOCK LED is On. See
section 3.10.1 for a full description of the various edge code numbering
modes available in the 4025TR.
The timecode and film number logical generators are mapped to the LTC
and VITC generators by the GEN ASSIGN menu when the 4025TR is
operating in local mode. The logical generators are mapped using the
Codes and Outputs tabs of the configuration screen when using the
KeyLog TRACKER™ software.
The VID TC, AUD TC, VRDR and LRDR1 keys in the display key group are
used to display either the Video or Audio logical timecode generators, or
the VITC and LTC readers on the front panel display.
characters of the front panel display are used to prompt which data is being
displayed. The TIME / UB key selects whether the time or user bits is
Model 4025TR Film Footage Encoder Manual
When the 4025TR is
The 4025TR also
When the
The leftmost
Page 3-36