Pathetically slow renders sometimes...

megabit wrote on 8/9/2010, 9:57 AM

Is this normal that with effects like the Mike Crash Dynamic NR and Unsharpen Mask, rendering speed drops to a crawl?

I can see it especially with codex like WMW and AVCHD, but even the MC MPEG-2 is slowed down (without those FX'es, my XDCAM EX material renders with the latter at the full 100% of all 4 cores).

If you happen to see the same with your installations, what's the culprit here:

- one of those FX'es (which one - I suspect the NR), or
- the codec other than MC MPEG-2 ?

Comments welcome

Piotr

Comments

Steve Mann wrote on 8/9/2010, 10:35 AM

This is likely normal because the fx are changing a lot of pixels in *every* frame. A compressed codec like AVCHD or MPEG will take even longer because Vegas has to recreate every frame between the iFrames to apply the fx. Then it throws much of that data away to recompress back to the original codec.

If you use an uncompressed intermediate, it may apply the fx faster, but you have to weigh the time of creating the intermediate with the time saved during editing.

Steve Mann

megabit wrote on 8/9/2010, 10:38 AM

Your reasoning makes sense, but the burden associated with such encoding should utilize all the computing power available - and it's running at some 24%, sometimes regularly going up to 85% for a couple of seconds.

And no, HDD is not a bottleneck here...

PS. Tried your suggestion to make an uncompressed intermediate - the same speed of 25% CPU at avi rendering!

fldave wrote on 8/9/2010, 12:05 PM

If Mike's effects are not multi-threaded, then when it is doing it's thing, the most you would see on your box is 25% (100% of one of 4 cores). When it finishes its thing and Vegas does an encode/compress step, then it can conceivably bump up to 100% of more than one core.

Maybe that is what you are seeing?

megabit wrote on 8/9/2010, 12:51 PM

This really does make sense!

Just bit the bullet and ordered the Neat Video plug-in. Not only is it 64bit - I also hope it is multi-threading...

Thanks,

Piotr

Dave_OnSet wrote on 8/9/2010, 1:25 PM

Piotr,
I bought the Neat plug-in and am very happy with what it is able to do, but I just take it for granted that it will significantly slow down my rendering process. Don't expect it to be a speed demon - working with full 1920x1080 HD files (and having it do comparisons of several frames to determine what is noise and what is sharp detail) requires a lot of computation. For pieces of any significant length I've settled on figuring out settings with short tests and then letting it work overnight based on my findings.

John_Cline wrote on 8/9/2010, 4:35 PM

While Neat Video does have a temporal component, it is primarily a spatial noise reduction filter which looks for patterns that match the noise sample which you give it. It's quite a bit more sophisticated and effective than any other temporal or spatial noise reduction algorithm. It does require some serious CPU horsepower for any kind of processing speed, but it is multi-threaded and the results are WELL worth it.

Dave_OnSet wrote on 8/9/2010, 4:48 PM

My apologies if I implied that Neat required frame comparisons. I will reiterate that I'm very happy with it. I tend to use it in cases where I need +18 gain on my EX1 to see anything, or where my GoPro HD Hero is pushing its auto-gain to the max. The results using Neat have made it worth many times the price of admission. I have found that so far I've been getting bettter results combining the 'pattern noise' aspect of the program with its 'Temporal Comparisons' features, though it could be that I'm not yet experienced enough with it to be any kind of expert.

Skratch wrote on 8/9/2010, 4:51 PM

I just purchased Neat Video the other day and it's pretty amazing. I'm doing HDMI captures of Super 8 film... not only does it clear up digital noise, but it reduces film grain too. I did a test render of some Neat Video corrected footage last night, AVCHD... it processed about 2 frames per second. I'm using an i5 650 with 4 gigs of RAM. unfortunately I have to run this system on 32bit Vista Ultimate because my HD film capture software doesn't have a 64bit version yet, and won't work on a 64bit OS.