Digibeta To AVI Files Via Avid

mrdbdigital wrote on 10/27/2006, 3:02 PM
I have 4 hours of digital betacam tape that I want to edit in Vegas Video on my home system. At my workplace, I have access to an Avid Media Composer system where I can digitize the tapes via SDI into the Avid.

I would like to digitize them as AVI files and take them home via an external hard drive, and I would like to maintain broadcast quality. The tapes are short 5-10 minute segments that I can do as individual AVI files, as I know the files will be quite large. (I have a 500 Gb portable dirve for this)

Can anyone suggest what AVI template or parameters to use on the Avid to create AVI files that will load into Vegas?

Also, any suggestions will be appreciated!

db

Comments

Coursedesign wrote on 10/27/2006, 3:25 PM
The first thing to do is to do a decent color correction while on the Avid, because you have to kiss off the last 2 bits in the luma when transferring to Vegas.

Vegas is 8-bit only (other than that it can do cuts-only editing of 10-bit footage), but by color correcting before truncating, you preserve as much as possible for the final output.

500GB doesn't go far for uncompressed, so you either have to do multiple runs or compromise.

A compact choice would be Serious Magic's DVCPRO50 codec, if you either have that on the Avid or can install it. About 26 GB/hour, $199 as I recall.
farss wrote on 10/27/2006, 3:41 PM
Why go uncompressed?
I thought Avid's 4:2:2 codec can be used in Vegas?
It'd take around the same space as the Sony YUV codec.
Coursedesign wrote on 10/27/2006, 5:29 PM
4:2:2 can be either compressed or uncompressed, these numbers just refer to the color sampling.

I'd guess you're referring to Avid's huffYUV codec which should be compatible with the Win32 codecs available for Vegas.

HuffYUV is simply a mathematically lossless Huffman encoding of YUV video, i.e. the same quality as uncompressed but taking up less disk space (more CPU usage though).
rmack350 wrote on 10/27/2006, 6:21 PM
HuffyUV is a free codec and can be downloaded here: http://neuron2.net/www.math.berkeley.edu/benrg/huffyuv.html

Vegas works fine with it as long as you have ample disk throughput. I'd definitely run tests before taking it on faith that I'd be able to edit, though.

Rob Mack
John_Cline wrote on 10/27/2006, 7:17 PM
Avid's proprietary codecs are available for free on the Avid web site. Just install them on your Vegas machine.

John
vitalforce wrote on 10/27/2006, 9:58 PM
You guys have the soul of seafarers. A different vocabulary but the same spirit.
[r]Evolution wrote on 10/28/2006, 8:09 AM
Firstly... you will NOT be able to capture .avi files into Avid.
Avid works totally different than VEGAS. Avid NLE's capture OMFI files NOT native .avi files. (You can do a web search to learn more about OMFI files.)

If you capture via Avid... you will then need to export your media to .avi or .mov or something VEGAS can read. You're talking about a very time consuming process if you decide to go this route.

I would suggest using VEGAS for capture to completion.
Maybe you can use Scenalyzer to capture if it keeps more color information. 8bit vs 10bit. Of course you will still only be 8bit once you hit VEGAS no matter what. In my experience (I edit on Avid Adrenaline), I have seen no significant color difference in VEGAS & Avid.

If you'd like your colors to be 'Richer'... add a Color Curves or Contrast Filter (or whatever you dicide) and adjust to suite your taste.

If you decide to capture using Avid... you will merely be adding more time to your edit. That's about all.
Coursedesign wrote on 10/28/2006, 10:16 AM
10-bit vs. 8-bit has nothing to do with "richer color."

It's about having wider exposure latitude, and if the finishing will be done in an 8-bit NLE like Vegas, picking the best 8 bits out ouf the 10 in the source DB footage, at least on a per clip basis (and yes, there's more you can do, but let's keep it simple here).

Once those 8 bits have been picked, there isn't anything that can be done to restore what was there in the shadows/highlights, but by picking judiciously it is likely (depending on footage) that you can get a better picture than with just idiot truncation.

If quality doesn't matter, then why shoot DigiBeta?

Just pull out ye olde VHS camera and "make the colors 'Richer' by using Color Curves or Contrast Filter and adjust to suite your taste."

Grrrr. Sorry, I just can't help reacting to this.

Who cares about an .AVI export? Minimal work, and the end result will be what it deserves to be.
farss wrote on 10/28/2006, 3:02 PM
To say nothing of the fact that SCLive only captures via 1394 which in NTSC land means you're not only down to 8 bit but your chroma sampling is 4:1:1. Sure you could save a bit of work by shooting DB and using a J30 deck to capture straight into Vegas and the results will look better than if you shot DV25 in the first place, the bigger chips and better glass on the DB cameras help no end.
But you are still throwing a LOT of usable data away.
IF your final delivery is only DVD AND you're working in PAL (Where DV is 4:2:0) then going down the above route I'll admit I've been hard pressed to see the difference HOWEVER my sources were already graded DB that was downconverted from HDCAM and/or 35mm.
I've no experience doing this in NTSC but I'd suspect there'd be quite a difference in the relative outcomes.
Bob.
mrdbdigital wrote on 11/24/2006, 6:38 PM
Thanks for all the advice.

The digibeta tapes I have are copies of 1" material. This is a blooper collection from TBS, so the quality varies all over the place. I wanted to transfer the digibeta tapes to my Vegas system, since the original 1" tapes are dbx Type II encoded, and I have long since lost the decoder. (The digibeta copies were made without the dbx encoding). I have access to a 1" machine, so it sounds like I would be better off to go directly into Vegas video from the 1" tape master. I have a firewire converter to get analog NTSC into my computer. I don't remember the model, but I think it is a canopis (sp?) that will do DVCAM 50..

Is there any way to remove the dbx encoding from the original 1" tapes with a dbx plugin for Vegas or Sound Forge (I have both).

Thanks again for all the advice!

db
farss wrote on 11/24/2006, 10:59 PM
Hm,
our 1" machines have the Dolby boards in them, I thought they were standard issue?
Apart from that given that the best you can get out of a 1" machine is composite then a decent analogue to digital converter such as the ADVC 100/300 or SD Connect is probably going to be more than adequate.

If you're really stuck for the Dolby decoder board, I might be able to source one for a loan / donation, bear in mind though I'm literaly on the other side of the planet. What make and model 1" machine do you have access to ?
All our machines are PAL but the audio board shouldn't care.


Bob.
Spot|DSE wrote on 11/25/2006, 7:41 AM
Farss probably has the best answer, because to answer from the software side, I'm not aware of any method via software to remove/access the DBX decoding, and DBX1 is likely almost impossible to detect due to the shape of the compressor. It's essentially just a 2:1 encode compression and 2:1 decode expansion, but it's not as simple as adding an expander to the track and expanding. The gain point could change depending on the signal content, and also has frequency relevance. Been many years since I worked with DBX/DBXII stuff, but in the early days, this was a nightmare with DAWs, and I don't believe anyone has created a DBX decoder.
BandPro used to have some decks on the shelf for legacy, maybe you could rent a machine that has a DBX card in it locally?
John_Cline wrote on 11/25/2006, 10:49 AM
Emulating dbx noise reduction in software wouldn't be a trivial task.

Anyway, there are currently two Model 122 dbx Type II decoders on eBay. One auction ends in 7 hours from now. It looks like you can buy it and get it delivered to your door for under $50. The other one's auction ends on the 1st of December.

John
mrdbdigital wrote on 11/25/2006, 10:49 AM
Thanks for the offer of the loan of the dolby card, but this is dbx type II, not dolby. My machine is a BVH-1100, and old beast, but still working. I have an old consumer dbx decoder, so I'll probably try and make that work, although getting the levels right may be tricky.

db
farss wrote on 11/25/2006, 1:31 PM
You're right, the board(s) we have are the standard Dolby SR boards.

I have to agree with Spot, all this legacy stuff has become a problem to deal with, in your case I think you're lucky, someone had the foresight to label the tapes with the compression system used.