Who wants up to 12 times faster DV rendering ?

HPV wrote on 10/8/2001, 12:22 AM
Yep, I just figured out a biggie for all DV Vegas users. Rendering at Preview quality speeds up rendering in a big way with NO QUALITY LOSS.
A few days ago I was learning the full meal deal on how the OHCI output works. Seeing that fields aren't used on anything "recompressed", I started using the preview render setting when using "pre-render video" . Looked really good. So today I did some major testing. Many differnt clips, titles with sharp edges zoomed to fill screen, scaling video,still frames, just about everything I could think of to show off a qulity loss. I rendered everything in both preview and best quality. All video was forced to render via the "broadcast colors" filter at track level. Used titles to know which was which on playback. Built up a project in Studio DV for output. Jumped from one version to the other for each clip 5 times in a row. Sent OHCI output to D8 camera, Svideo to SVHS deck, composite to 32" RCA.
You can't see a differnce. My eyes didn't want to believe it, but it's true. DV renders out the same at both quality settings. But one is much, much faster. One 10 second part had "pan/crop" moving a title and the video. Best quality took 11 min. 54 sec.
Preview did it in 1 min. 38 sec.
I'm sure I'll do some more testing as I still can't believe it. But man this is looking good.
Yeeeee Hawwwwwwww ; )

Craig H.

Comments

darr wrote on 10/8/2001, 9:26 AM
How much had the file sizes changed?
DR
Thanx for tips.
InformationSponge wrote on 10/8/2001, 11:50 AM
Interest conclusions. I'll have to try this myself tonight and see what I get.
HPV wrote on 10/8/2001, 2:07 PM
>>How much had the file sizes changed?
DR
Thanx for tips.
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They don't, it's DV. Always the same. I think it's 3.8MBsec. Wow, I'm still as freaked about this today as I was last night.
I knew something was really funky slow about Vegas when I'd compare it to what Studio DV could do on say a title with shadow and outline over a DV clip. On my 1.3ghz P4 Studio DV will do it in 4 times the length of the clip.
Vegas with new CG at best quality will take 20 times the length of a clip.
Guess what preview quality does it in. Bingo...... 4X
Same as Studio DV. Same beautifully rendered DV output. I'm using the MS Codec in both, as I nuked every Pinnacle DV codec that loaded onto my machine. I would suggest the same for everyone that has Studio loaded on their machine.

Craig H.
jdozz wrote on 10/8/2001, 3:08 PM
Yep, this works and I kept asking the technical experts why with no response. Fast and no quality issues.
tinklady wrote on 10/8/2001, 7:25 PM
Can the prerenders be sent back to camera as such?
DougHamm wrote on 10/8/2001, 11:09 PM
Did some testing tonight on my PIII-550. Here's what I found.

1) Adding broadcast colours filter and rendering using either Preview or Best resulted in no quality OR time difference.

2) Adding a title and rendering (no broadcast colours filter this time) resulted in substantially faster rendering when set to Preview. Copied a frame of each to Photoshop, layered using Difference, and saw no difference. This unfortunately wasn't a perfect test as I _should_ have followed that up with a magic wand colour select with 0 tolerance - in other words, there may have been very subtle differences my eye didn't catch, but Photoshop would have. I'll test that again.

Why with the titler and not the other? Could it be less to do with the quality of the DV render, but more to do with accuracy of calculations? This could make particular differences with titling and other generated media, but perhaps under the right circumstances lead to a loss of quality. Or maybe not. This should be an easy question for a SF rep to answer for us.

-Doug
dpearce wrote on 10/9/2001, 7:30 AM
I mean no disrespect and I certainly do not want to demean you, but I was told this hint from day-one using VV. We render mostly Real and WM7/8 and closing the preview window altogether produces a HUGE render speed difference (depending upon the quality setting of the preview window).

In other words, the preview window affects other destination file formats.

Reason: Because the picture must be rendered twice (once for the preview window, once for the output file), render times are longer.
Dreamawake wrote on 10/9/2001, 10:24 AM
Ok..you're confusing me now...how does the "faster" rendering work then? What do we have to do? RENDER PREVIEW from the TOOLS menu but close the preview window as well? Then take the numberered .mpg or .avi file from the root of the Vegas folder? Is that what we're talking about? And in rendering it as "PREVIEW" that is as opposed to making it GOOD or BEST quality? Will this work with footage taken from a VCR or does this just apply to DV footage taken from a camera?
HPV wrote on 10/9/2001, 10:35 AM
>>I mean no disrespect and I certainly do not want to demean you, but I was told this hint from day-one using VV. We render mostly Real and WM7/8 and closing the preview window altogether produces a HUGE render speed difference (depending upon the quality setting of the preview window).
-----------------------------

If you knew about the speed boost for using preview quality on your final renders, great. Wish someone would have told me months ago.
As for closing the preview window, it makes now difference in render times for DV files on my P4 with a Geforce II video card. Maybe for other codecs it would help.

Craig H.
HPV wrote on 10/9/2001, 10:46 AM
>>Why with the titler and not the other?

You are right. Filters like broadcast colors, HSL,
brightness contrast render at the same speed with preview or best render quality setting. But film effects, swirl, wave filters all see a major speed boost with the preview setting.
Anybody at S.F. have the low down on this? Is there any visable quality difference between preview and good/best on final DV render ?

Craig H.