What IS Rendering ?

UKharrie wrote on 2/6/2014, 6:02 PM
This may seem a trivial Question, but I have an issue with a reliable version of Movie Studio.
This Preview run-time is about 2minutes, so it's not exactly LARGE. However, there are some experimental audio features along with fairly normal Text - but unusually there is no moving stream... That is unusual as all "movies" so far have used a high proportion of Movie-clips. The Audio features are "Pitch-Change" - but each file is quite short.
That's the "Background" to what appears to be a curious Problem ( or Effect perhaps?).
As the Render process does its stuff, I see the Preview WIndow showing me what I presume is the state of the Rendering - so when it comes to the end, I presume it has done all the work that's required.
However, this particular Project, appears to run out of Time ( reaches Zero), when the time-bar is saying 91-95% is finished. ( it's shorter if I make the closing title very simple). When I see this time=Zero it will stay there and the Preview window shows clearly it hasn't completely finished.
Now here's the ODD thing - If I look at the HDD (where the Renders are stored), the Rendered file is there! Yet curiously it will play and stops at exactly the same place the Render did. Sound and Vision are perfect and appear to follow exactly the Editor's intentions.

So. I'm still of the opinion that Rendering looks at each time-element (call it Frames?), applies whatever "effect" is specified in the (dot)vf file, taking the original files from the Project Folder, and outs the result in the Rendered file (dot) m2ts.

Yet, I'm left wondering why this recent Render doesn't go to the end? Just what is the Rendering program doing, stopping about 5% short?

I'm using v10 Production suite.

BTW - I tried to render a very short (15-sec.) Title sequence, which I know has given no problems and that will Render completely in a few minutes, more-or-less as I'd expect. I know the Render is complete when the screen changes to Finished, Play File, Exit and so on. However the problem Render is still 91% on the Time-bar after a half hour from reaching Zero.

EXIT
To close the process, I have tried Cancel - but that is ineffective. The only cure is to Shut Down (Win 7-32b) which forces a closure. When I Start/Boot the PC, WIn 7 doesn't mention the shutdown and when I fire up Movie Studio, It is happy to open the offending (dot)vf project.
It's as though one of the files has put the software into Suspension......but without telling me.

Thoughts?

ODDs
I tried using the Track-controls..... and played with the Mute and Solo options....but curiously I found the Solo didn't work how I expected (ie by clicking), Reading the Help file seems to direct me to use ALT and then click - this seems to have restored the Solo operation . . . . I mention it just in case others have discovered this can corrupt the Render Operation.
-Mindyou, if I was writing the program I'd scan for illegal states, before starting the Render process,
- rather like the OS will check a Destination is writable.

Comments

Chienworks wrote on 2/6/2014, 6:20 PM
Some codecs have an extremely long GOP (group of pictures) structure, and the entire group must be examined and rendered beginning to end before it can be encoded and output. Note that rendering and encoding are actually separate processes, even though what Vegas calls "rendering" does both seemingly simultaneously. So, if you have a long-GOP output like MTS, Vegas does in fact render all the way to the end as you see in the preview window, but at that point has not yet begun encoding the last GOP. If you've fed it a stream of images that take a lot of effort to encode then it may take quite a while to do that last bit of encoding. And of course, the longer the GOP is compared to the overall length of the project, the greater the disparity may seem.

Note also that Vegas often builds sections of the output in temporary files, which it then must copy and append to the output file. This too can add some extra time to the process even after it looks like the last frame is done.

As far as your extreme examples, you're probably hitting upon a set of circumstances that put Vegas in a very long and inefficient loop. I had one i was doing ages ago that involved B&W, cropping, slow motion, and a few other effects, on the last 8 seconds of a 15 minute project. It did everything up to that last 8 seconds in a flash, then spent several hours on the last part and only getting through a few frames. I gave up, canceled it, then copying the last 8 seconds over to a separate project and rendered it to an uncompressed file in a few minutes. I then replaced the last 8 seconds of the original project with this new uncompressed, "pre-rendered" version, and rendered the entire 15 minute project in about 20 minutes.
Paul E wrote on 2/7/2014, 5:27 AM
If you have nothing on the video track try inserting an empty event (right click over video track) and stretch it out to the length or just a little more that you need. If that doesn't work try using generated media such as solid black.
UKharrie wrote on 2/7/2014, 9:02 AM
Chienworks,
Many thanks for the details, but as you suspected the Project I have is very short and is Audio-only (apart from some minor Text messages).

I haven't changed the Rendering settings AFIK and an earlier 15-seconds "Starter Title" rendered itself in short time, despite having a lot of keyframing.

You gave an example where your closing frames were heavily worked and I wonder if you recqall if the Time to completion reached zero (ie before the several hours completed)....as my experience is that ( and the time-bar) is only a "guess" and as it progresses it can be updated - of course it's not smart enough to know how much the remaining files will take, so I'd expect it to show your Project was going to be a few hours..... was that the case, I wonder?

as stated earlier, My Project reached Zero "Estimate" but hung at 91-95% for well over half-hour - the % remaining fixed. . I suppose I should give it a go "Overnight" - but I concluded I'd "upset" the software somehow - esp as the Rendered file m2ts appeared to be complete up to final frames.
UKharrie wrote on 2/7/2014, 9:09 AM
Paul E,
Thanks for the suggestion, is this to give it something "Easy" to work on?

There are Titles present almost throughout the 2-minute Project - I use them to describe the Audio events.
As posted above, before I try the "Overnight Render" I'll give Paul E's suggestion a go on a single track.

BTW I notice that some Movie Studio v10 tracks are "Audio" - and won't accept Video - and some are "Video" - and appear not to accept Audio . . . I can understand this helps workflow and might reduce confusion (although I'd prefer having the original audio+Video tracks linked somehow, perhaps by colour?

Does anyone know if it's possible to Wrong-foot the Software by putting the media in the wrong place - could I have done this, and M-S accepted it.. by mistake.?
Paul E wrote on 2/7/2014, 10:25 AM
The idea of the black was to give it continuous video as your titles are not. (thinking about it an empty event is perhaps not the same thing).
There must be something wrong to contemplate overnight rendering, I cant imagine what audio processing takes that long. A pitch change on a wav file takes no significant time here. Try removing the titles and render the audio just to a wave file. It sounds like it's getting stuck at some point. I've had that on odd occasions and go to the point where it stops and fiddle with the transition or whatever. Also it is possible to have errors in media files that can cause hangs.