How much real-time can you get with dual Opterons?

BGil wrote on 6/14/2004, 12:51 PM

I'm looking to build a new PC and I'm wondering what kind of real-time output I'll get if I use dual Opterons (1.8ghz) as opposed to dual Athlon XP 3200's. The difference in price is about $200 per processor and $200 for the motherboard or about $600 total. Specifically, I'm wondering about what kind of quality and how many streams I can output via firewire to my camera (which would be in record mode).

Would I be able to get 4 streams of DV (or later HDV) with basic cuts/dissolves/fades and a few effects to output at full-quality and framerate through firewire?

Any help would be appreciated and any experiences or suggestions with dual proc Xeons, Athlon XP/MP's or Opterons, relavant or not, are welcome.

Thanks.

Comments

Jsnkc wrote on 6/14/2004, 1:02 PM

Well, since Vegas doesn't have real time output capabilities (unless you're talking about the preview window) you will have to render no matter what. The speed of the rendering is about all you will increase. And what that speed is....I'm not sure, maybe someone else can answer that one.

BGil wrote on 6/14/2004, 1:08 PM

Yes, I was talking about the preview window.

I've heard about Mac users using the external firewire preview as real-time output and was curious as to how weel a dual processor system could do the same.

Jsnkc wrote on 6/14/2004, 1:25 PM

The only problem is that vegas doesn't output the audio through firewire unless you render and do a print to tape so all you will get is the video.

Spot|DSE wrote on 6/14/2004, 1:26 PM

Vegas can easily use the firewire as a real-time output, whether from a slow-boat computer or a dual opteron.
On the VASST tour showcase event, i use a BOXX dual FX 51 machine, and it's GREAT!!! Wish I owned it. Fast, great output to external or internal, getting 4 streams of DV with no issue. Problems start with lots of FX, etc. Depending on the effect, Vegas on duallie will do well.
To support Jsnkc's comment though, you won't be able to print to tape without at least a pre-render. FCP can't do this either, unless you've got a hardware assist card.
Vegas doesn't take full advantage of duallies, audio goes to one thread and vid to the other. You see the main advantage of duallies with lots of audio and lots of vid on same project. Or when you've got multiple versions open at once. If you don't plan on background rendering or lots of versions open at once, then I'd go single rather than duallie and spend the $$ on the RAM and other peripherals. Save your pennies for the Decklink card. My .02

BGil wrote on 6/14/2004, 1:42 PM

"To support Jsnkc's comment though, you won't be able to print to tape without at least a pre-render. FCP can't do this either, unless you've got a hardware assist card."

So even if my camera can record analog/digital inputs the firewire output won't print to tape?

Please excuse my ignorance as I'm just a rank beginner in the video world.

"then I'd go single rather than duallie and spend the $$ on the RAM and other peripherals. Save your pennies for the Decklink card."

Why would I want a decklink card for DV or HDV? Will it add hardware assisited rendering to Vegas?

Spot|DSE wrote on 6/14/2004, 1:57 PM

K...I'll try a different way of explaining.
You must render to print to tape via firewire. To print to tape without rendering, you'll not be able to do this, as non-interleaved files don't travel down the firewire cable. Audio is heard from your sound card/speakers, and preview of video will happen via firewire.
I think you're confusing real time preview with real time output. Very different. Vegas provides realtime preview in a method that no one else can currently do. Print to tape requires either:
A. Rendering
B. Hardware assistance.
Vegas doesn't currently have hardware assistance available, therefore you need to render everything before printing to tape.
Decklink would benefit the HD and SD guy, but now understanding you are just starting out with all this, you probably aren't doing HD at this point.
http://www.boxxtech.com is a great place to start looking at prebuilt, professional machines.

busterkeaton wrote on 6/14/2004, 2:01 PM

The firewire output will print to tape.

However first the final output has to be rendered to DV.

Real-time has two different meanings in the NLE world.

Real-time preview is can I see my effects? Vegas can show real-time previews over firewire to a TV monitor. If you add intense effects or multiple streams of video, Vegas will still show you a preview, but it starts to drop the framerate. How much in drops the framerate or when it starts to drop the framerate depends on what kind of computer you are using. Here dual Opterons will probably allow for the most effects/video tracks possible among desktop computers. A single P4 will also you to see real time previews too, just not with as many effects/tracks as the dual Opterons, but certainly enough to edit and to use lots of effects.

Real-time output means when you print to tape a 1 hour DV program will take 1 hour. Vegas has to render to DV before printing to tape. So any titles, transitions, effects. etc have to be rendered during the print-to-tape process starts, so it would take longer than 1 hour to complete. If you are doing just DV to DV, then output would be quicker.

BGil wrote on 6/14/2004, 2:34 PM

Okay, I think I understand now. Thank you.

Am I correct in thinking that the Decklink cards are just SD/HD capture and output to tape/deck/camera with no hardware assisted rendering?

"Vegas provides realtime preview in a method that no one else can currently do."
So Final Cut Pro HD still requires rendering to print to tape, right? So I guess I was just mislead by apple's slick (a.k.a misleading) marketing. In what way is the Vegas real-time preview superior to that of FCP HD on a dual G5?

Spot|DSE wrote on 6/14/2004, 3:01 PM

yes, you were mislead by Apple's "Emporer has no clothes" hype. I also wrote a book on FCP and Soundtrack, know those apps well. FCP is a good tool, but like all DV apps, needs render or hardware to print to tape without rendering.

filmy wrote on 6/14/2004, 4:24 PM

>>>ave your pennies for the Decklink card.<<<

here here. :) Good thing is that they don't really require a lot pennies either. :)

BGil wrote on 6/14/2004, 8:15 PM

So the guy who posted this is lying.

"Not really, no. I output to something. I encode it, sometimes. I can go directly to tape, which is in real time. I can go to DVD, which requires me to encode it into MPEG 2, which takes time. I can take the Motion project directly into Final Cut Pro and edit it or add it to a project there.

Final Cut Pro has many real time FX and real time streams and real time transitions. There is no rendering of these when outputting.

If you are using After Effects plug-ins in Motion, you will have to render those sections, but if it's like Final Cut Pro, and I think that's a safe bet, you don't for the features that are real time in the application.

Even iMovie doesn't require rendering when you output, but goes directly to your DV tape in real time. The rendering it does do, it does when you add the transition/FX, in the background.
"

jaegersing wrote on 6/15/2004, 2:05 AM

There's a review of FCP 4 at the link below, that also states that FCP can output in realtime provided you don't add too many effects.

Edius V2 from Canopus can give RT output through OHCI 1394 as well. Again there are some constraints on what effects you can use in RT, but this one I have tried for myself and it does work, even with 4 video streams. I still prefer Vegas for everyday editing though, it suits me much better than Edius.

Richard Hunter

http://videosystems.primediabusiness.com/ar/video_apple_final_cut_5/

BGil wrote on 6/15/2004, 9:34 AM

Thanks for the review. Basically it looks like a dual 1.42 G4 has less "real-time" capabilities as my Athlon XP 1800+ with Vegas. I guess Apples claim of "all but three effects in real-time" means you can preview all but three effects in realtime and not necessarily at high quality and full-frame rate with a dual 2ghz G5. Frankly, I'm kinda dissapointed as the ads (and the whole Apple site) make it seem like "RT Extreme" is really extreme but in reality it doesn't even match what my Vegas 4 or 5 can do in software.

thanx for the help everyone