Audio sync NTSC Win 95 fix

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May 12, 1996, 3:00:00 AM5/12/96

Audio sync is always going to be a problem with Non-Linear printing to
NTSC video. I have found some tricks that work pretty well. Use this setup
only as needed, because, in essence, it cripples Windows 95 performance.
When playing back a continuous stream of video, you only want your
computer to do one thing -- play the AVI. But Windows 95 is designed to
do all kinds of things in it's "spare time." It tries to read ahead and
guess what will be needed next. It tries to move files to a temporary
swap file on your hard drive. All this extra activity causes, either your
video to skip frames, or your video stream to be buffered into memory for
split seconds, while your audio plays without skipping or buffering. After
a few minutes (or seconds) it gets out-of-sync. This is an extremely
annoying problem which Miro, Adobe (and everyone else) blames on anything
but their hardware or software. I think the culprit is Windows 95. To beat
it, you have to turn off some Win 95 features. Go to -- Control Panel,
System, Performance, File Sytem and change "read ahead optimization" to
none, next click on: Troubleshooting and check "disable write behind
caching for all drives." Next (do 6 megs of ram, because Windows probably
won't even boot with less) go to -- Control Panel, System, Performance,
Virtual Memory section, check "let me specify virtual memory setting" and
check "disable virtual memory." Next reboot your computer and after
Windows starts double click on the AVI file, or start Media Player and
play your file. These settings seem to turn off Windows 95 incessant
housekeeping and allow the video to play uninterupted. Also make sure your
finished AVI is on a different (physical hard drive) than Windows 95. EIDE
drives if pushed will skip frames, but probably stay in audio sync. You
have to experiment with different audio interleave and compression methods
in Adobe Premiere. I use 1 second audio interleave and IMA ADCP
compression. After you are done change these settings back and reboot your
system. This works pretty well on my Pentium 120, 24 meg ram, Miro DC20

Good luck, Mike Reinholz, Seattle.

Tom Wilson

May 20, 1996, 3:00:00 AM5/20/96

I have found that the ps and nice utilities
made for WindowsNT work in Windows95. They
allow you to change the priority of your
video program...

Tom Wilson - Flagstaff, Arizona

In article <4n5jfj$>,


May 20, 1996, 3:00:00 AM5/20/96

When I turn off virtual memory I find that I have problems editing my
video in Premiere 4.2 that I don't ordinarilly have. (I get out of memory
messages.) Are you recommending that we turn off VM only to playback an
avi file (to copy to tape?)

David Moffitt

May 23, 1996, 3:00:00 AM5/23/96
to EdBlanco

You should turn off VM only when outputing to tape...

BTW, when VM is off, thats a great time to defrag your drive since it
wont be interupted as much and won't have pieces of the swap file all
over the drive..

Hope it works!


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