Rendering time

JoaoRanhel wrote on 10/7/2003, 3:06 PM
I've captured a clip of about 25 minutes. I cut 5 minutes in the middle, and applied fade in/out at the beginning and the end. So I need another AVI file of this edited clip. When I choose render, it is taking more than an hour to render it.
How long does it take to render a clip of 5 minutes in DV? What am I doing wrong? Is it normal?

When capturing I’ve experienced some echo in sound, but the sound is OK, after capturing I’ve checked it in Sound Forge. Why does it happen?

Environment:
(Pentium 4 – 2.4 GHhz – 512MRam – PYRO – Gforce4 – Cheetah 72GB )
I’ve checked Vegas to ignore third part codecs and I’m not using Windows DV codec.

Comments

jbrawn wrote on 10/7/2003, 3:38 PM
Yours is a similar system to mine.

When I'm rendering unchanged AVI files, it runs about 2x real time. So a 20 minute video takes about 40 minutes to render.

John.
johnmeyer wrote on 10/7/2003, 4:38 PM
I just tested a render of a one minute DV clip, with a five second fade to black at beginning and end. The total time: 56 seconds on a 2.8 GHz P4.

I then rendered to a different physical disk and the time dropped to 28 seconds.

I therefore suspect that the big problem here is a hard disk I/O bottleneck. I had suspected this to be the case as soon as I read your post, because when doing cuts-only editing, most of the "rendering" is simply reading the original AVI file and then copying it directly to a new AVI file, and whenever a computer has to simultaneously read and write massive amounts of data from the same hard disk, it gets really bogged down.

If you do not have a second physical disk, I am not sure what to suggest that would make your results faster. Perhaps someone else will have some suggestions. (I would suspect that playing around with the size of disk buffers might help a little.)
JoaoRanhel wrote on 10/8/2003, 11:48 AM
2x real time would be good for me. My problem is that my system is very slow to render AVI DV. What would be the problem?
Udi wrote on 10/8/2003, 11:58 AM
Is your source and target format the same - in FPS, Resolution, field order etc?
What DV format are you using?
Is the source and target on the same disk?

Udi
JL wrote on 10/8/2003, 12:57 PM
> When capturing I’ve experienced some echo in sound, but the sound is OK, after capturing I’ve checked it in Sound Forge. Why does it happen? >

Could the echo be coming from your camcorder's speaker?
Chienworks wrote on 10/8/2003, 1:16 PM
As for the echo, check VidCap's Options / Preview Audio. I normally run with this turned off. It is slightly delayed from whatever direct monitor you may have on your video source (camcorder's speaker, television speaker, stereo system connected to the VCR, etc.). It also tends to be intermitent and it seems to take a surprising amount of processor power. Turning it off allows me to capture with zero dropped frames on an 866MHz P3; with it on i'll usually drop a few dozen frames every minute or so. That's not many, but zero is definately better.
JoaoRanhel wrote on 10/8/2003, 9:06 PM
>Is your source and target format the same - in FPS, Resolution, field order etc?
•Yes, I've just captured the movie (through IEE1394 Pyro – DV NTSC format) then I insert it in the timeline and render as another movie. It has taken about 1 second per frame to be rendered!

>What DV format are you using?
•Originally my tape is mini DVCAM (camera PD100). Does it matter?

>Is the source and target on the same disk?
• Yes, but I’ve tried to copy the source to the HD where the Vegas is (IDE 80G) and render to the other HD (Cheetah) and the result is the same!
As the temporary drive and folder I’ve chosen the faster HD – the same where the program will save the render result.

I've used XP home and DX9 (all updated).

Udi wrote on 10/9/2003, 5:25 AM
It sound like a problem. In my case, PAL, on HT 2.6Ghz with 512MB RAM - it does about 1:1 render time - 1 sec to do 1 sec AVI to AVI.

I am NOT using DX9, when I installed it (runtime 9a) I had many problem and crahshes during capture.

What is your CPU utilization when rendering?, anything else working?
Spielberg wrote on 10/9/2003, 7:19 AM
I would be lucky if the redering was 2x the real time. Yesterday I started to render my first film but I had to cancel since it indicated that my 27 minute film would need 24 hours to render!
I use a 1.3 Ghz AMD Duron. However, I also use the same disk for both source and target, but I suspect that something else is wrong.

Does anyone has any ideas what I should do?
I rendered my film as wmv format instead, and that took over 6 hours....

//S

BillyBoy wrote on 10/9/2003, 8:56 AM
It has been reported countless times rendering times is relative to CPU horsepower AND the complexity of your project. A project that has minimal tracks and little or no filtering applied should render fairly fast. We're talking typically 2X to 8X IF you have a fast processor.

However if you have a project with six video tracks, 4 audio tracks, apply certain filters like unsharpen or Median, then all bets off. Your rendering time will mushroom to 10, 20, 50 times or more. Its the nature of the beast. Other things that slow rendering down is converting from one file format to another, changes in frame size, rate, stuff like that. Again, the reason is you're asking Vegas to do a lot more work.