User Manual

Vertical Blanking Information
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c
You can preserve VBI information for JFIF, uncompressed, and MPEG IMX resolutions.
You cannot preserve VBI information for DV resolutions.
n
In the majority of cases, you should not preserve these extra lines when you perform a digital
cut. Only do so if you have a special need for the information.
Vertical Blanking Interval Line Ranges
Your Avid editing application can capture 248 lines per field in NTSC or 296 lines per field in
PAL. For NTSC, only 243 of these lines are in RP-187’s production aperture. For PAL, the
number is 288. The additional lines in each field are located immediately above the active part of
each of the two fields. These lines (5 per field in NTSC and 8 per field in PAL) can be used for
carrying additional data.
The following table lists the extra vertical blanking lines for both NTSC and PAL:
Displaying and Preserving Vertical Blanking Information
Avid editing applications using Avid input/output hardware automatically preserve the extra
lines of vertical blanking information when you capture footage. You can choose whether to
display the lines and whether to retain the lines when you output your sequence as a digital cut.
You might want to preserve the following vertical blanking information:
• Edgecode or key number information for a film project
You might want to preserve edgecode information to easily identify the source film reel for a
clip. In this case, the edgecode information would have been originally inserted during the
telecine process.
• Closed-captioning information
If you are repurposing a finished sequence for another market, you might want to retain
closed-captioning codes that were added after the tape was output from the Avid system.
This would let you perform some basic editing on the recaptured sequence and not to have to
reapply the closed-captioning codes afterward.
Field Video Raster Line Number Ranges
NTSC (5 Lines/Field) PAL (8 Lines/Field)
Field 1 16-20 15-22
Field 2 278-282 328-335