noone seems to have asked the fundamental questions with video input ....
so i need to ask them-
what camera source ntsc or PAL?
what refresh rate and frame rate are you running the screens at?
what frame rate is catalyst set to playback at?
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there is no difference between drivers ( mine or AS )-
the only difference is that the active silicon dmg installs a quicktime driver for use with other quicktime applications-
the quicktime driver does not have good low latency performance- and should not be used- though it does work in catalyst.
those system commands you detailed - uninstall the quicktime driver-
the problem as described is not a driver problem -
but a frame rate thing- i await more information
1. depends on the frame rate of the video input -
2. the frame rate of the display -
3. and the playback rate set in catalyst application-
you see if the person is using NTSC which may or may not be close to 29.97 Hz - and their screen is 1024x768 which is 60.02Hz- it doesn't evenly divide- into the screen refresh - and every minute or so - something has to give ...
the video input as described is working correctly-
what refresh rate are your screens?
and your video input?
and catalyst frame rate?
there arent any driver issues with phoenix - there is no quicktime driver-
any issues with phoenix installation need to be referred directly to active silicon- there arent any software/driver issues-
Thanks for your input Richard... glad to see you getting in on this one.
the source is NTSC
catalyst is set at 30fps
Refresh rate is 60.02 I think (1024x768) for the output to led controllers
Based your comments it would be better to lock the playback to some division of the refresh rate I assume?
source ntsc. so somewhere in the region of 29.97Hz ( though not necessarily accurate )
is this a pro camera or an cheap camera setup?
which LED product is/was it?
dmx or dvi?
suggest as a potential first step you try setting frame rate to screen div 2 and see whether it gets better or worse
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its related to the problem of how to play back the 23.98 movie we had before-
its the same kindof deal-
NTSC video camera signals dont fit neatly into dvi/vga/LED controller refresh rates.
I know I'm jumping in a little late here, but I can also recommend the TVone boxes. One thing to note however, is that at least on the 2355, while it can genlock, you need to genlock based on your output format (i.e. tri level for HD, Blackburst for SD) While on an imagepro, you can use black to genlock and HD signal. Not a huge deal, but one you need to know if you are using them. There are actually a few devices out on the market that let you take a blackburst or trilevel signal in, and use that as a reference out for the other type of sync. that are fairly cheap.
Thanks for the continued support Richard.
The cameras are all professional and are going through GV DAs.
The LED is Barco SLIGHT with LED PRO controllers running DVI from Cat to Led Pro
I'll try what you suggest as soon as I can. Could be a bit before I get to try this. Wish this was not the case. It seems like this would fix it. Any other thoughts on this subject?
on a side note... if you wanted to take the time to explain precisely how that few seconds of jittery video happens I would love to hear it from you Richard. The concept is simple enough however I am curious as to what happens with the buffers or whatever it is at that precise time. Understanding is power :)
first of all we need to do some experiments by changing some settings-
there are many different possibilities - sometimes unexpected -
in this situation there isnt usually a technically correct answer -
we have to try to find the best visual solution by changing graphics card settings and catalyst playback rates-
I made these settings available because these situations arise a lot.
and we have to find the best solutions-
i have a lot of situations where the timecode is 25Hz- but the screens only run at 60Hz- for example with element labs controllers used in europe-
sometime the client has to sync to external source without timecode available and the external source runs a little fast or a little slow-
sometimes the frame rates - screen outputs and timecode are all mixed up and cannot be changed...
sometimes projectors really dont like working at 75Hz- only work at 60Hz - but show is at 25FPS... eurovision 2004
i had a show last year with martin lc panels- and they took really strange input rates- i cant remember exactly- but completely non-standard - and the show was run from a laptop- and laptops have refresh rates you cannot change....
and on and on...
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a very quick technical metaphor is this-
you have 2 conveyor belts running side by side- they have fixed bucket positions- they are not continuous belts- one can transport 899 cabbages per minute- and the other runs slightly faster at 900 cabbages per minute-
how do you get the cabbages from one conveyor belt to the other?
what happens if you cannot exactly or precisely measure the positions of the cabbages?
what happens if the rate of the conveyors changes slightly all the time?
or the positon has some mechanical hysteresis in it?