rendering to uncompressed AVI problems

clang

clang

Veteran
I've owned Vegas for several years (now using version 7) and have found it rock solid for editing half a dozen short films. But recently when completing a epic 10 minute film (my longest ever :) ), Vegas suddenly began freezing partway through renders to uncompressed AVI files. I found a workaround - render the first and second halves separately, which was fine as I could then rejoin them in my DVD authoring program - but i'd still like some help in working out what I was doing wrong in the first place.

Symptoms: film has no problems in editing, plays back in preview mode fine, earlier versions (with placeholder jpeg stills and temp audio instead of video footage, but otherwise the full 10 minutes long) had rendered fine. Now however it got 50-60% through a render before the progress indicator froze, disk activity stopped, and eventually Vegas had to be manually ended via Ctrl-Alt-Del. Retrying and fiddling as per below diagnostics altered the exact point of the freeze, but otherwise gave the same results.

Diagnostics:
1) I immediately suspected lack of disk space or fragmentation, but after a defrag my work disk confirmed I had 15 gigs of free contiguous space, and the problem continued. (I also ran CheckDisk in case I had hardware or directory problems, but no problems were found.)
2) given the greedy space requirements of uncompressed AVI, I also wondered whether I'd merely hit XP's file size limit for a NTFS disk volume (about 2 gigs?). However, as above, earlier 10 minute versions had rendered fine. And as I was rendering to uncompressed AVI, surely any 10 minute film would take no more space as any other 10 minute film?
3) as my main reason for wanting the avi file was to then put it onto DVD, I then tried rendering to MPEG2 instead (using the DVD Architect-compatible output options) but alas once again froze. So file size was not the problem?
4) rendering to WMV worked fine (although that was no use for DVD authoring).
5) instead of uncompressed, should i have tried a different compression codec? I was trying to maintain best picture quality, but was this the wrong way?
6) should I have tried rendering out to tape, then reimporting from that tape?
7) any other hints and tips from makers of long fims?

thanks
Clang
 
just because I wanted to avoid losing any quality due to compression (having seen so much badly over-compressed stuff, especially on the internet).

but as the most quality I'll ever realistically need is:
a) mini-DV tape, for entry into film festivals etc
and b) DVD quality, for ... well, DVDs :)
perhaps it is complete overkill.
But also, I'd wanted to keep a best-quality archive of the completed film to avoid keeping gigabytes of source footage forever, so had (perhaps naively) thought an uncompressed AVI file would be the best option.
 
You will generally speaking get an uncompressed file size of roughly 1MB per frame. (up to 1.7 MB for 873x480@32bit)So 10min at 24fps = about 15GB so available disk memory may well be the problem as you mentioned you had 15GB free.
 
Just checked, and both 'half' AVI files are around 1.2 gigs each, i.e. the hypothetical file i was trying to create would presumably be 2.4 gigs. I'm using PAL SD resolution by the way, 720 x 576 pixels from memory, not that i think that would make any difference.
 
Those numbers seem quite low to me for uncompressed assuming 5 min chunks.
Can you right click on the rendered avi and check the properties?
I suspect that file of 2.4 gigs is compressed.

I ran a quick test rendering a 1 min uncompressed avi to double check my predictions.

Here are the rendered file properties:

Width = 720
Height = 480
Duration = 1:03 (69 seconds)
Frame rate = 24fps
sample size = 24 bit (no alpha channel)
compression = Uncompressed.

File size = 1.48gb

---
So based on my calculations as follows:

Approximate file size = width X height X bytes_per_pixel X fps X seconds.
So I have 720 X 480 X 3 (3 bytes = 24 bits) X 24fps X 69 = 1.716GB.

The reported size of 1.48 GB differs from 1.72GB I think because it's in how Windows reports file sizes. The approximation calculation also does not take into account the audio which was compressed in this case so I would expect an even larger size.

At any rate the prediction of 1MB per frame is about right and calculates to 1.036MB based on the settings I used.

So again, please check the file properties and make sure that file is not compressed.

---
Barring all of that, it could maybe be the audio is still compressed. It has to be set independent of the video. There may also be a peculuarity in the codec that causes it to fail above a certain size. Just a thought.
 
clang said:
just because I wanted to avoid losing any quality due to compression (having seen so much badly over-compressed stuff, especially on the internet).

but as the most quality I'll ever realistically need is:
a) mini-DV tape, for entry into film festivals etc
and b) DVD quality, for ... well, DVDs :)
perhaps it is complete overkill.
But also, I'd wanted to keep a best-quality archive of the completed film to avoid keeping gigabytes of source footage forever, so had (perhaps naively) thought an uncompressed AVI file would be the best option.
Click to expand...

It's definitely overkill. If your source material is DV, DV is fine.
 
David Jimerson said:
It's definitely overkill. If your source material is DV, DV is fine.
Click to expand...

Wouldn't that compress it again though? Or is that a misconception in this case? I've heard when recompressing video it's best to use different codecs. (I'm learning this stuff).
 
I was using the PAL DV template (Audio: 48,000 Hz, 16 Bit, Stereo, PCM Uncompressed. Video: 25 fps, 720x576, Lower field first. Pixel Aspect Ratio: 1.093. OpenDML compatible. PAL DV video files compatible with Sony Video Capture.) modified only to change audio to Mono as I had no stereo sound recorded.

the last two above posts raise a vital point - is the data on a mini-DV tape 'compressed'? If so, which compression codec best matches it? As my source material is DV tapes, I have no need to output to 'better' quality than that even if it is possible...
 
Just a couple quick comments. I think there is a difference in archiving raw dvx footage and vegas-edited footage. Specifics I dont know.

Also here is a link someone gave me for a lossless codec. I have not used it and know nothing about it but here is the link...

http://neuron2.net/www.math.berkeley...g/huffyuv.html

I'll step aside now as that's about all the help I can offer and am curious about the answers myself.
 
If you are working with DVX footage then rendering to DV is (while yes, is recompressing your footage) fine for almost anything you would ever do. Especially if you are capturing, editing/color grading in one pass, then rendering out to a final master .avi. The Vegas DV codec (default) if perfectly fine for this.

Yes, from your camera (DVX) the footage is compressed 5:1 from the original with 4:1:1 color sampling.
 
although I'm looking at upgrading to something like a DVX100 (or the PAL equivalent, the DVX102B), I'm currently using an elderly Sony Handycam, so my tape footage is probably even more compressed (and/or poorer quality) than that.
 
If it's a DV or Digital8 Handycam, it's the same compression. It's very likely lower-quality, but not because of the compression.
 
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