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Re: 3/4" dailies without windows and curtains



This is strange... most compression systems (JPEG and
MPEG) preserve the VBI.  It's especially easy to do this
since the VBI usually contains no picture info, just
relatively low-rate data.  If it really is the case that
even the new Avid PCI cards trash the VBI, that should be
a firmware fix, no?

As for the sometimes-reported 1-frame errors, I have run
across some Avid digitizing discrepancies that were not
really Avid problems.  SOme folks use mid-cost TBC's on 
their source Umatics, and sometimes these are frame syncs,
which cause an offset between picture and RS-422 TC.  Same
delay may cause a discrepancy between recovered VITC and
RS-422 TC.

On Fri, 10 Jan 1997 09:34:12 -0500  Joel Swan wrote:
>>In a message dated 1/8/97 Jeff "sync this!" Kreines wrote:
>>
>>The one unfortunate disadvantage to VITC is that most nonlinear systems
>>discard any info stored in the blanking to conserve space.  If only this
>>information remained tied to every video frame (and I don't mean through a
>>database, but simply by keeping a few lines of the interval with the frame)
>>life would be a lot simpler!  Is the Avid Media Reader working yet?  It reads
>>3-line VITC and creates a file from it....
>>
>
>This disadvantage still exists in the Avid products. The systems based on
>the NuVista+ video board did not capture the VITC lines.  The newer systems
>based on the Studio video board do capture the lines but after compression,
>they are not useable.
>
>The Media Reader is now able to read the 3-line Aaton/Evertz VITC standard.
>A new version of the Media Reader firmware is available through the normal
>customer support mechanisms or via the Avid BBS which can be downloaded
>into the Media Reader to support 3-line.
>
>Some customers have reported timecode offset problems using this new
>firmware (off by 1 frame, etc.).  These problems are being investigated.
>
>Regards,
>
>Joel Swan
>

------------------------------------------------------------
Bill Topazio, VP/Engineering     bt at mte.com   v:212-907-1225
Manhattan Transfer / Edit        New York, NY f:212-687-2719
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