Maximum render length?

Barry W. Hull wrote on 4/2/2013, 8:13 PM
I have spent the last month rendering project files. The projects are anywhere from 3 to 25 minutes long. The render times range from 5 to 28 hours. Chroma key and several effects make for long render times. I have a fast computer.

All of the files have rendered except one, the longest one. I have tried over and over and over, wasted about two weeks of my time, trying all sorts of combinations to get the longest file rendered.

The REALLY frustrating part is that Vegas doesn’t crash until it gets down to under an hour left in the render, then voila, Vegas crashes. Yeah, I’ve sent some rather obnoxious messages along with my information to Sony, please forgive me.

Anyway, two questions, does anyone know if there is some sort of bug that rears its head when render times go above a certain time length? One sort of odd thing, the render times start back over to zero when they go above 24 hours, rather than simply continuing to count.

Second, is there an easy way to “hook” two rendered files together without re-rendering? I thought maybe I could render the file in two parts, then "hook" them together.



PeterDuke wrote on 4/2/2013, 8:26 PM
What codec is used?

Vegas can smart render some files. Then there are tools such as VideoReDo.
PeterDuke wrote on 4/2/2013, 8:27 PM
You could also try rendering to a lossless or low-loss intermediate format and then join the bits.
videoITguy wrote on 4/2/2013, 8:43 PM
My point of view is that is a rather fruitless effort to search for the goal of the longest productive render time. We know of anecdotal evidence where people have done renders that cross the 15-18 hour mark...but you run into several obstacles when attempting long periods of time.

Generally most complex renders hang before they complete because of an anomaly on the timeline. Timelines are the largest source of halting rendering in any scenario.

Otherwise -given even a less complex problematic timeline you have issues:
1) Exceeding the limits of Win OS and hardware issues: auto sleep or hibernate is just one ot them. Sometimes you cannot control all of this even though for short periods - not a problem.
2) You can also run into controls of overheating, circuit tolerance etc in prolonged machine runs.

Here is how I handle large project with complex rendering issues.
A) Breakdown the project into sub-sections - render each part concurrently in a networked server farm- such that each render is occupying its own machine. I can easily conquer an otherwise 8 hour render in less than an hour spread across say 4 machines.
Rendering is done to an intermediate stage.
musicvid10 wrote on 4/2/2013, 9:26 PM
Is the final render size going to be > 4 GB?
That is a limitation of the MP4 container. There is a workaround, but not sure Vegas encoders have it.
Peter Riding wrote on 4/3/2013, 2:56 AM
I regularly make MP4's over 4gb (I use dual layer DVDs) so I think thats fine. Through versions 10, 11, and 12 I think. Can't remember about earlier versions.

My longest single render was 17 hours just recently.

I haven't come across crashing on such long renders but my workaround as suggested earlier in the thread would be to render in separate low loss sections then join them up for a final render. This is also good if you spot a mistake in one of the sections - no need to re-render the whole long project :- )

Barry W. Hull wrote on 4/3/2013, 6:07 AM
The only problem has been with this one particular long render. Sure, maybe it is coincidence that the longest project is the one with the problem, but it seems that the length is the only difference among the projects. We use a standard formula in each project, opening music, title, talking head, ending music, etc.

The rendered file will be about 1.5 gigs, MainConcept AVC/AAC. I’ve rendered almost 100 files using the particular settings. I had some help about a year ago from a very experienced Vegas user, I am confident there is nothing “odd” in the settings.

I don’t think my machine is overheating. I use Ultimate S Pro to batch render. There have been several occasions where renders have occurred in immediate succession for over ten days. I have a brand new computer that does nothing except for Vegas tasks, sits quietly in the corner rendering.

Thanks for those suggestions. I’ll try two sections, then maybe VideoReDo to join them.

Later, just out of curiosity, I might load the project to Drop Box, see if any of you gurus can render this in one long file.
Chienworks wrote on 4/3/2013, 8:30 AM
I've done many renders of projects that were over 5 hours long, renders that took over 40 hours, and renders that resulted in files over 120GB. All of them were successful. I don't think it's the size/length that matters so much as the source material. I had one just recently that was only 100 minutes rendering an MPEG2 source to MP4 and it failed every time about 99% of the way through. I can only assume there's something wrong with the source file at that point. It was captured with a stand-alone set-top DVD recorder and has quite a few issues. Other MPEG2 sources that i've created in Vegas don't have issues.

What i finally did was to render it to a DV MXF intermediate, and was then able to re-encode that intermediate into MP4.

One thing i was curious about though is that at one point you mentioned 4.7GB DVDs. Are you making standard video DVDs? If so, rendering to MP4 is a poor choice. You should be rendering to MPEG2, since that's the only valid format for DVDs.
ritsmer wrote on 4/3/2013, 9:49 AM
.... and if you render to mpeg-2 then you can split the project into a few parts, render each to your final mpeg-2 format - and then smartrender these parts together.
Smartrender does not decode/encode and so it does not decrease your video quality - and you will not lose all your 28 hours for the full render if something crashes while rendering - but just render time for one of the parts.
Barry W. Hull wrote on 4/3/2013, 11:28 AM

Do you happen to know specifically what was the problem with your project file? I have examined the project, almost frame by frame toward the end, to see if any glitches or trash shows up, but it all appears normal to the naked eye, just like every other file.

Also, I think you are referring to another post, I am not making DVDs. These files are for uploading to Bright Cove.

Yeah, I'll try rendering two parts, see if that works.
VidMus wrote on 4/3/2013, 2:27 PM
If I use drivers later than 296.10 I will get this problem. With 296.10 I can render more than 2 hours of video.

TheHappyFriar wrote on 4/3/2013, 8:40 PM
The best way to figure out where the issue lies is to make regions and render out your project in regions.

The only times I've never had a render finish was because of memory on my system or a bad file. Besides that I've had no limit.
musicvid10 wrote on 4/3/2013, 8:52 PM
@Peter Riding,
DVDs don't use MP4.
Peter Riding wrote on 4/4/2013, 1:47 PM
Perhaps I should have made it clearer :- )

DVD is the delivery method. The client then does whatever they want with the MP4 which I've burned onto the DVD.

As alternatives I don't really trust flash drives longer term compared to DVDs and cloud delivery is not yet practical because fast upload and download speeds here are not common.

Yes they do get told to backup their DVDs :- )

Barry W. Hull wrote on 4/5/2013, 12:16 PM
Ok, so I dropped a marker at about the half way point, and rendered the second half, took about 14 hours. It rendered without issue, so far so good.

Then I tried to render the first half, it failed at 98%.

So I dropped another marker splitting the first half into two sections. I then rendered the two sections of the first half, and both rendered without issue. Terrific.

Now I need to put these three pieces together into one file.

Bottom line, there are some crazy things going on inside Vegas.
Barry W. Hull wrote on 4/5/2013, 1:25 PM
The three rendered files rendered into one file in 24 minutes, as opposed to 28 hours for the entire project, so I am assuming it smart rendered, finally got this project rendered. Thanks for the tips.