Video sync offset more than 8 frames?

Luxo wrote on 8/8/2002, 4:41 PM
Does anyone know if there's a way to offset the video in an external monitor by more than 8 frames? I'm talking about the setting in options -> preferences -> video device. When previewing through either my camera or DV deck it looks like I need to offset at least another frame or two. Since I'm doing music video style editing, I need frame accurate cuts, and it's painful to edit in the Vegas preview window.

I searched the internal preferences tab but couldn't find anything. Any help?

Thanks,
Luxo

Comments

SonyDennis wrote on 8/8/2002, 8:57 PM
What camera and deck are you using? 8 frames is over a quarter of second, and way more buffering than a DV device needs to do, so why would they?
///d@
Luxo wrote on 8/8/2002, 9:39 PM
Beats me, man. Maybe the computer is holding the information back before sending it out the firewire?

I'm using a JVC SR-VS30 miniDV / SVHS combo deck. But I believe the latency is just as long when run through my Canon XL1s. Is this really a rare occurance? I never thought much of it, but I've haven't needed frame accurate cuts until now. Anyway, is there some way to increase the number of frames? Like I said, I'm just one or two off. Let me know how I can help.

Luxo

PS. My system specs.....
Dell P4 1.8Ghz
512MB RDRAM
200GB hard drive space
Intek 21 1394 card
jetdv wrote on 8/9/2002, 9:08 AM
What is the operating system? I have heard that WinXP adds a ONE SECOND delay over the firewire port making the offset needed to be about 30.

It would be BEST if the offset was simply a textbox where a number could be entered. If you wish a limit, allow numbers from 0 to 100 - but allowing from 0 to 8 just *MAY* be too restrictive.
SonyEPM wrote on 8/9/2002, 10:16 AM
We just tried this out (again) in XP- lipsync is no sweat (4 frames, the Vegas default). What exactly is your hardware chain?

Also, I believe AVID DVXpress 3.5 has a problem with external monitor lipsync. The RUMOR is that XP introduces a 1 sec delay, but it isn't XP's fault, it is an AVID issue.
jetdv wrote on 8/9/2002, 10:36 AM
The problem was mentioned in a Cinestream forum. Apparently when using LiveDV (i.e. preview over the firewire - sound over the speakers) under Windows XP, the offset must be set to 30 or so frames where in Win2K and Win9x the offset was around 4. The problem is ONLY in WinXP. I cannot state first-hand whether this is a problem with Vegas as I have not tested it on an XP machine. However, it *MIGHT* be wise to include the option of higher numbers. Here are some quotes from the Cinestream forum:


"You need some updated files, and there is
a one second delay in LiveDV video output caused by Microsoft's XP
drivers for OHCI firewire. But people are making it work."


"I am running CS on a Sony Vaio with Win XP home. I had some issues to
start with. I resolved these by downloading all the patches and updates
from Discrete and Microsoft. With these in place the system has been
stable and efficient. I do have the 1 sec delay as spoken about elesehere
in Live DV."


"I'm running CS v3.1 on a Dell Inspiron 8200 Laptop under the
WindowsXP Pro Operating System (OS) (P4M 1.6 GHz, 512 Mb, 30 Gb HD, Maxtor
80 Gb FireWire). I add a +30 frame offset for playing back on an NTSC Sony
audio/video tube-monitor for final evals, to compensate for the 1-second (30
frame) audio delay with LiveDV selected."
Luxo wrote on 8/9/2002, 3:39 PM
I am using XP, but it sounds like that may or may not be the problem. I definitely don't have a full second delay -- closer to 10 frames.

My hardware chain is.......

Windows XP
Dell P4 1.8Ghz
512MB RDRAM
200GB hard drive space
Intek 21 1394 card
JCV SR-VS30 miniDV / sVHS deck
Sony VHS deck
Samsung television
SonyDennis wrote on 8/9/2002, 5:25 PM
Any chance that Samsung TV is trying to do deinterlacing or any other video processing? Is it a projection set?

Have you tried other DV gear to see if the delay is in the DV device or Windows XP?

What method are you using to measure this?

///d@
Luxo wrote on 8/9/2002, 9:16 PM
The TV isn't doing anything to delay the signal. It's a cheap $200 job, and if I pull up the menu on the JVC deck while playing video, all the buttons respond in real-time.

Yeah, like I said, I get the same result if played through my Canon XL1s, so it's almost definitely the fault of the computer somewhere.

I'm testing this by creating a Vegas project with alternating generated solid colors (orange and blue). When orange is on screen, an emergency broadcast 'beep' plays. When blue is on, it's silent. Blue lasts twice as long as orange. Ghetto, but it works.

Further thoughts?

Luxo
SonyDennis wrote on 8/9/2002, 11:15 PM
Sorry, forgot about the XL1s. So, then you're measuring this test pattern by eye & ear, or some other means?

It sounds like something XP is doing, we'll continue to look at it.

In the meantime, if you are brave and don't fear RegEdit, you can go to:

HKEY_CURRENT_USER/Software/Sonic Foundry/ExternalMonitorSettings/1.0/Metrics/IEEE 1394 v2.0

and change the B0 value. It will be in hex; the thirteenth value is the latency offset. Double-click on B0, double click on the 13th byte (probably 04 or 08) and type 0A for ten, or 0B for eleven, hit OK. Do not use the preference page to change the setting, or it will get bounded to 8 again.

///d@
Luxo wrote on 8/10/2002, 6:28 PM
Rock on, Dennis. Thanks for looking into that for me. Let me know if I can help test any WinXP problems.

I am testing the latency with eye and ear, yes, and comparing the results on the television to the results in the Vegas preview window.

Luxo
Cheesehole wrote on 8/11/2002, 4:10 PM
>>>I cannot state first-hand whether this is a problem with Vegas as I have not tested it on an XP machine

I run XP and the 1394 preview appears to be spot on. I'm using an SIIG 3-port 1394 card with TI chipset with a Sony DSR-11. it may be off by a frame or two, I haven't checked that closely yet.
jetdv wrote on 8/11/2002, 11:19 PM
Thanks for the location where this value is stored. However, it also indicates how easy it would be to change the slider to a text box and make the range 0 to 255 since that location can already hold that range of values. It would definitely add a lot more flexibility - even if most values were never needed.