ext preview: glitches

FuTz wrote on 2/18/2002, 5:49 PM
When I use the "preview to monitor" mode passing thru my DV Cam (OHCI,FireWire), I get glitches I don't have when I use the VV3 preview on-screen monitor (on the software...). I allowed 200MB to memory in the "Preferences" box, "Video" tab under "Options". Even if I allow the maximum memory (254MB), I get these glitches. I even get a blue screen on the beginning of each cut I try to preview...
How can I achieve a good, solid external preview?
I run under Win2K, have 3x128MB total memory, ADS tech Pyro FireWire card (Texas Inst. chip).
Thanks!

Comments

Control_Z wrote on 2/18/2002, 7:05 PM
My first guess: A hardware problem. Can you check the 1394 cable and DV cam on another system?
FuTz wrote on 2/18/2002, 7:59 PM
No. I don't have another system. But the cable is brand new. Of course I know I can buy a "defective brand new cable"... But my hope was it had to do with the fact that it's a different type of screen... even if it has a lower res than my computer screen. I'll try to find another cable (1394) and check it out, but I guess I'll have to buy another one... Nothin to do with some precise tweaks I could make to work it out?
FadeToBlack wrote on 2/18/2002, 9:11 PM
FadeToBlack wrote on 2/18/2002, 9:12 PM
FuTz wrote on 2/18/2002, 11:01 PM
Yeah, all of it... bouh-ouh-ouuuuuuuuuh (violins, tears and sadness reaction shots on this one...)
Caruso wrote on 2/19/2002, 12:34 AM
Futz:
Are you talking about previewing prevously rendered material, or previewing unrendered material that you are editing? Also, while you were pretty specific about your RAM, you don't mention the speed of your processor.

My system (900 mhz) simply isn't fast enough to allow Vegas to play previews of unrendered FX to my external monitor without jerky results. If I render (or selectively pre-render), external preview is fine. If I preview video to which no FX have been applied, it plays fine on my external monitor, also.

If I add some fades, slo-mo's, text overlays and such, those sections get very jerky.

If your system is capturing ok and printing to tape ok, I would not waste money on new firewire cabling, it's gotta be ok, as well.

Buying a faster computer (can't believe that I can now double my processor speed by spending almost half what I paid for my "leading edge" system less than two years ago) would probably cure most of the jerkiness. I'd love to hear from someone on this who is using a 1.8 ghz or faster machine.

Caruso
BD wrote on 2/19/2002, 9:21 PM
I'm using a new custom-turnkey Athlon XP 1800 machine with 1 GB RAM and three harddrives. Its unrendered preview output is great. On a 3-minute movie that consists entirely of end-to-end dissolves between short clips (and a music track), the FireWire output (passed thru a camcorder to a monitor) is perfect except for some roughness on slo-mo dissolves. The final rendered output is completely perfect. I'm very satisfied.
FuTz wrote on 2/20/2002, 5:27 PM
Thanks for all the answers and here's some more details...
I got a 1000 Athlon processor inside. ABIT KT7-Raid (NO raid array though... enough problems I had to fix with this board just to run it under minimal, "standard" operating...). I noticed if I make the preview from the timeline, it tends to be better, compared to previewing from the media pool. I really don't know why though...
In fact, what's annoying me is that it's ok-dookie on the computer screen and as soon as I go with this ext. mon. switch, that's bad on my tv screen. Isn't it suposed to be the same signal? If I play a cassette on my cam and send it to tv, it's ok. Same setup with firewire hooked up and... scrrrrrtch... glitches.
If I render before, it's ok. But what I want is just a bigger previewing screen!
DougHamm wrote on 2/20/2002, 5:49 PM
This sounds the same as an issue I've had for eons, and I figured I couldn't be alone. My config:

Abit KR7A-RAID w/o any RAID
Athlon XP1800+
1GB RAM
ADS Pyro card
WinXP
etc.

I find when switching between timeline and trimmer, and just basically jumping around the interface, the firewire card takes several seconds (3-5) to reinitialize each time. During this period the display is blue; if I wait long enough then the picture displays.

If I play at that point, it's fine except that the picture is a little herky-jerky every so often.

By playing with alternate cam drivers I found that I could get the herky-jerkies to go away - but that solution wasn't practical so I'm back to jerkies. But nothing I do can get the firewire display to initialize quickly. Used to work fine for me under Win2k with an Intel system.

Some things I've found that i'd like you to confirm:

1) This delay in initializing the display is not confined to Vegas; ScenalyzerLive and other firewire apps do the same.
2) It's only on playback, not capture
3) Print-to-tape functions are smooth as silk with no dropped frames, or jerkiness
4) Any playback within the video preview window is perfectly fine - this is firewire only.

I've got some theories ranging from DirectX8.1 (installed by default with XP - are you running it?), my Sony DVMC-DA2 and WinXP, some funniness between my sound card and firewire card eating up PCI bus time...I don't know what else to blame. The delay in initializing the display makes it hard to use the external preview effectively, and the jerkiness I experience (I'm almost positive XP is to blame here) just adds to the frustration. I now rely on the external preview for barely anything more than ensuring my titles and such are within the safe zone.

-Doug
HPV wrote on 2/20/2002, 7:35 PM
Used to work fine for me under Win2k with an Intel system.
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Yep, works fine with Intel and ME. But I get the same stuttering on previews with a 1.3ghz/128MB system. Previewing a straight clip from the timeline at draft or preview says 29.97, but still hicups here and there. Not a biggie as I use the OHCI preview more as a frame buffer and stepping thru frames. I've heard that print-to-tape and Vidcap both have buffering vs. timeline preview. Don't know if anyone is getting straight clips to play glitch free via OHCI preview with any speed computer. Anyone?
I get my editing preview window out to TV via my Geforce MX2 card. Switch box lets me bounce it and OHCI via my camera. Frame rate flat whoops up on OHCI. Double the framerate on lots of stuff. Color and brightness are very close to source DV. Size is only 640x480, but that does show full action safe area. Ends up being a TV screen cropped inside the monitor. Never does the herky jerkeys on straight clips. Let's you gain even more framerate by dropping to 360x340 for checking motion effects. Frame based display for easy on the eyes editing, but you must check for jitter via OHCI. Hence the switch box. So it's really no different from using a second SVGA monitor. But, it lets you use the same monitor you use for OHCI preview. Cats meow would be dual SVGA for timline and TV out on a third windows screen.
Geforce2MX tv out cards go for about $50.00 these days. New Geforce4 MX series ($135.00) have an onboard Video Processing Engine. 720x480 interlace is one of the TV ouput options. Don't yet know if it will output a "windows" screen at that resolution. That would rock though. BTW, all Geforce 4 cards have dual display of one kind or another. VPE engine only in MX line.

Craig H.
FuTz wrote on 2/20/2002, 10:09 PM
Dough :
I confirm: yes to # 2, 3 & 4...
I'll be back, just noticed sound on my Capturing is non-syncro now... checkin' this out and I will read the last 2 replies a 2nd time...
A taleure!... and thanxz!
DougHamm wrote on 2/20/2002, 10:58 PM
Thanks guys - Craig, it's actually somewhat comforting to hear that the firewire stutter isn't unique to me. I'd say misery loves company, but really it's not that big a deal.

I thought it might have something to do with taxing the PCI bus between audio and firewire, so tonight I loaded up a bunch of music on both my SBLive! AND my M-Audio Omnistudio, then printed to tape - still no stuttering. Only when previewing, and even then with all audio tracks muted, so I think your comment about a lack of buffers is a valid one indeed. I've looked through the Internal settings and played with values to no avail, so perhaps this is something SF can address in future updates.

The aforementioned delay of 3 or so seconds during firewire initialization has me vexed, but again it's nice to see I'm not alone. I could handle it if VV only did it on startup (since it seems the delay is not exclusive to VV), but switching from timeline to trimmer causes it consistently. And worse yet, when you stop playback in the trimmer the video preview goes back to the timeline - so hitting Play again causes yet another 3 seconds of waiting...this is by far the more annoying issue.

-Doug
HPV wrote on 2/21/2002, 2:15 AM
The aforementioned delay of 3 or so seconds during firewire initialization has me vexed, but again it's nice to see I'm not alone.
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I get one 3 sec. sycn funky stuff when I first click on the ext. output icon, but once I'm in it bounces clean from timeline to trimmer. Not saying Vegas deals with this feature in any kind of useable fashion. But it's clean, damn VIA stuff.Grrrr,

C.H.
DougHamm wrote on 2/21/2002, 7:52 AM
Futz, HPV, what DV equipment are you previewing with? I wonder if it's device-specific. Also what versions of DirectX are you both running under 2k/Me, respectively? I can't rule out the VIA chipset as a contender, but what a weird symptom considering printing to tape works like a charm!

I find too that if I hit play from the timeline, then while it's playing go to the trimmer and also it play (so both are going at the same time) I can jump back and forth cleanly. So it's like a plate-spinning act: if you keep the firewire port active it doesn't reinitialize. But if you halt playback and then jump from timeline to trimmer it does. Untel HPV mentioned that he got that under Win2k, I was ready to believe it was due to WinXP being more interested in the goings-on of firewire devices (they show up in My Computer), thereby taking focus away from VV when idle. But I wasn't expecting someone to see it under 2k...

-Doug

-Doug
FuTz wrote on 2/21/2002, 1:45 PM
I run DirectX 8.1, Win2K service pack 2...
HPV wrote on 2/21/2002, 1:57 PM
Futz, HPV, what DV equipment are you previewing with? I wonder if it's device-specific. Also what versions of DirectX are you both running under 2k/Me, respectively? snip......... But I wasn't expecting someone to see it under 2k...
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Intel 850 chipset mobo, P4 1.3, 128MB, Win ME, DX 8.0, Pinnacle 1394 card, Sony D8 cam, Belkin 1394 cable.
I do NOT get a blue screen glitch between timeline and trimmer. Just once when I activate ext. monitor preview.

Craig H.
DougHamm wrote on 2/21/2002, 3:57 PM
Thanks guys - sorry HPV, I mixed you and Futz up when I mentioned you having the issue under Win2k.

Hmmm...maybe DirectX 8.1 has something to do with it? Under XP there is nothing but, so maybe I'll have to hold tight and see if things differ at all when the DirectX 9 beta comes out. Gotta love Symantec Ghost.

-Doug