I do not want a low quality preview, I want 1080p online. What perplexes me is that my processor use is not saturated and my RAID is way more than sufficient yet I am unable to playback the footage in real-time in Vegas. I can play back realtime no problem using windows media player.
I can get 23.976 fps if I set the preview to "auto" but that resolution is too low for me to make editing decisions based on picture quality.

EDIT - the bug below was fixed with a reboot -
In fact, the problem seems to go deeper than 1080p. I can't get 480p to play back in real time at full 640x480 even though I have plenty of ram left, 90% of my processor time is available and my RAID could problem play 10 SD streams concurrently without hiccuping. Why would I only be getting 18fps for uncompressed SD when the file type matches the project settings and no external monitor is enabled.

These low framerates are the case when I set the preview to "draft" and 8-bit color rendering with no effects present. This seems like a bug. Anyone?
-END EDIT-
Thanks,
Robert

Setting the 480p project aside for the moment, how do you tell if Windows Media Player is playing things at full frame rate?

I just rendered a couple of 5 second test files (noise textures) at 1080-24p. Using the Sony YUV codec I get a 487 MB AVI file-nearly 100 MB/s. Given what you're saying you ought to be able to handle that.

The second render was an uncompressed AVI which totaled 973 MB, close to 200 MB /sec, which sounds like it's close to your limit.

Your description sounds like a throughput issue rather than a CPU issue, but you ought to have enough throughput to play a Sony YUV file. If these are .MOV files you might be having some other wierdness as the stuff get's passed back and forth between Quicktime and Vegas, I suppose.

I'd still be calling it throughput, but maybe it's not the disc array. I just changed my project to a custom template - 640x480x23.976 and then made an uncompressed and a Sony YUV render. Both play fine for me.

Athlon X2 4400+
3 GB Ram
2 disc RAID0 on nvidia raid controller
WinXP Pro SP2

Thank you rmack350. Rendering the source video to Sony YUV codec did get me close enough to my goal for the time being. I am able to edit with real-time preview as long as I keep the rendering quality in the project settings at "Good" or lower. It goes below real-time on intense action, but I haven't fully tweaked yet and think I will be okay once I get used to the new codec.

One bummer for me is that this requires yet another transcode. I am already performing a transcode from HDV to uncompressed YUV in order to remove the pull-down from my 24p canon HV20 footage using hv20pulldown.exe. Since vDub can't render I will now need to render the uncompressed YUV footage into Sony YUV using vegas unless I can get vDub to recognize Sony's codecs which isn't the case out of the box. Getting that done is a question for the vDub forum I guess.

Thanks,
Robert

Sony YUV is a 4:2:2 codec so it's not quite the same as uncompressed AVI, but it's decent and ought to be plenty for anything short of compositing. Looking at the file sizes I posted it looks like it's half the size of a full 4:4:4 RGB AVI.

Allthough I don't know this for a fact, I think that uncompressed RGB is what Vegas passes through the CPU and RAM as you play the timeline. Or maybe the better way to say it is that an uncompressed AVI file contains the exact same content that Vegas would decode and display. The import of that should be that if Vegas can decode and preview a 1080x1920 stream from a Sony YUV file then I'm not sure why it couldn't do that from an uncompressed file, as long as you've really got the disc throughput.

You're saying you've got uncompressed YUV, which is not an option within Vegas afaik. You might try an experiment with that footage and render it, within Vegas, to a new track as an uncompressed AVI file. I'd be curious to know if you see any difference between the uncompressed YUV created by Vdub and the uncompressed RGB created by Vegas. Maybe there's a difference.

In terms of preview quality, "Best" is just supposed to add bilinear interpolation to make resized video look better. It's a lot more CPU intensive but as far as I know it shouldn't even come into play if all you are doing is puttung a clip onto the timeline and playing it. If you aren't resizing things then "Good" ought to be identical to "Best".

There is evidently a certain amount of overhead when playing clips from the timeline. People have been saying that a clip in the trimmer often plays much better than it would on the timeline. I don't know why this id but I imagine that Vegas is doing nothing when playing from the trimmer. It's probably in preview mode and certainly not checking multiple tracks or anything like that. If that's the case I'm not sure why your CPU isn't loaded more. Maybe Vegas has a list of things to check for each frame and the list takes enough time for Vegas to miss frames? (as an example, a certain other program I use used to check it's cache twice while shutting down. It was a progamming mistake that went unnoticed for about 6 versions of the program until people like me managed to build such massive static web sites that the double cache check was noticeable).

At this point I'd be testing other codecs to find something that will work. And I'd be pinging Sony about this, especially if you're finding that something more banal like uncompressed 480i also won't play. You do need to make sure that you're using a codec that Sony has to take responsibility for, like uncompressed RGB rendered from a Vegas project.

If it's not disc throughput, other hardware throughput, or CPU load, then my next guess would be something along the line of Vegas needing to complete too many tasks before sending a stream out for preview. It takes too long and Vegas skips frames to keep up. If I were a programmer, and I'm not, I'd wonder if Vegas is doing a task twice before previewing. That's show up more when the preview stream is bigger, I'd think.

Rob Mack

I can play uncompressed YUV until a certain bug develops. A fresh reboot will restore my ability to playback in real time. This bug that develops stays resident in memory because even when I close and reopen Vegas I still have slow framerates for all formats. I'm trying to determine a way to repeat this bug but haven't been able to determine when it happens, it just does.

I appreciate the good points you bring up. The RGB nature of the timeline is probably what I'm struggling with. When the bug is present, it doesn't matter what format, the preview window is always at most 3/4 of realtime.

Thanks,
Robert

Thanks,
Robert

Just out of curiosity and because I don't know how to do it, how are you making uncompressed YUV in vdub?

Rob

If your source is HDV, why not purchase/add an AJA Xena card and capture using the Sony codec anyway? No transcode time...

I am scoping my next step-up.

My PC builders are AJA UK-distributors and I am assuming fitters of these too. I can see a range of AJA cards from £200 > £1,700.

What suggestions can you make that would direct me in one direction or another?

Much to consider here . . .

TIA

Grazie

One thing that was never brought up was audio. I wonder if that could be a problem here. Maybe you've checked this but it'd be worth the time to turn off audio tracks, turn off wave forms, things like that.

Rob Mack

DSE,

>If your source is HDV, why not purchase/add
>an AJA Xena card and capture using the Sony codec anyway

How are you capturing the HDV content with this card, via the analog (component) output of the HDV camera?

--Rob

Hi Robert,
I know this post is a few weeks old, but I was searching the forus because of a simalar problem after installing Vegas 8 myself.

Could you check this, start a new project, add one clip. Set the preview screen to best, full and with simulate device aspect ratio turned on. Play the clip from the project media and check the frame rate, check next adding it to the trimmer and then in on the timeline.
See what frame rates you get.

You didnt mention if this was HDV or Intermediate format

Dont ever forget that vegas is decoding said file on the fly...

Sorry about that, DJ.
I am finding that regardless which format is used, either intermediate, HDV or standard DV. If I play a clip in either from project media window or from the trimmer window the frame rate stays at 25fps (pal), even with the preview set at the maximum resolution, but as soon as it is placed on to the timeline the frame rate can drop to as low as 3fps. This is with no other effects or tracks added. I do not think that this can be correct and think it may be a bug in the software. I needed some feed back to know for sure.
Ken

Auto-preview from the project media window, or anywhere else, is the same as playing from the trimmer. The clip is just played, nothing needs to be checked or calculated, there's no bilinear or bicubic interpolation (essentially "preview" quality).

Playback from the timeline ought to be just as smooth, at least that should be the design requirement, but in practice there's a lot more going on. This is not to say there isn't a bug, just that the two modes of playback aren't identical.

There's a signal flow diagram in the PDF manual that might be illuminating.

Rob Mack

O/K thanks, rmack
i'll take a look, I will post it again over the week end and see any body has time to check it out on there computer. many thanks for the reply.
Ken

Well, if you're getting just 3fps from PAL DV on the timeline then that's not right no matter what. Yes, the timeline has overhead compared to auto-preview or the trimmer, but that's a LOT of overhead.

But what the problem could be...that's not always easy. You could have drives not running in DMA mode, or something more serious hardware-wise, but I doubt that if you've got good playback in the trimmer.

You could have funky files...maybe they aren't really what they say they are.

Or it could be something odd in the project itself, like filters you don't know are running.

Anyway, the course is to narrow things down until you find it.

Rob