NTSC DV vs. Uncompressed AVI Confusion

Nathan_Shane wrote on 7/14/2004, 2:20 PM
Okay, I'm confused here now. I just read in another post where Spot suggested that if one needed to render to a new track, to use the NTSC DV over the Uncompressed AVI.

I thought Uncompressed AVI was completely lossless and wouldn't make any difference. Everyone talks about Sony's DV codec being superior in quality, so is the NTSC DV setting actually the Sony codec?

I thought that by selecting Uncompressed AVI that no codec was used whatsoever and that it was all pure raw digital video...am I thinking wrongly here?

I thought when Vegas pulls the video directly from the camera via firewire, isn't this the same "uncompressed AVI" format I mentioned above?

So if I want to keep the absolute best quality in a project, but perhaps I need to work in sections, using different .veg files to assemble later in one big project, should I always choose NTSC DV or Uncompressed AVI if I do have to render in sections before final project assembly?



Comments

Former user wrote on 7/14/2004, 2:24 PM
The DV AVI is a compressed format. The compression is done in the camera when you shoot. When you capture, there is no codec used, it is a file transfer of the compressed video.

If you render to uncompressed, you are taking compressed video and uncompressing it. this is useful if you plan on going several generations with effects. There is no more loss until you recompress for output to tape.

If you are only rendering a couple of times, then generally there is very littlel loss in using the DV codec. the trade off is the disk space used for uncom[ressed vs. the minimal quality loss of compressed.
BJ_M wrote on 7/14/2004, 4:28 PM
work a lot in uncompressed, lossless codecs or HD and your drives will end up looking like this (19 drives here) not including outboard network raid:

230-|=====================DRIVES STATS=========================
230-|
230-| Drive:C:\ Total [32.03 GB] Free [12.40 GB]
230-| Drive:G:\ Total [111.79 GB] Free [24.32 GB]
230-| Drive:H:\ Total [111.79 GB] Free [6.33 GB]
230-| Drive:I:\ Total [111.79 GB] Free [26.48 GB]
230-| Drive:J:\ Total [111.79 GB] Free [22.73 GB]
230-| Drive:P:\ Total [34.18 GB] Free [26.65 GB]
230-| Drive:Q:\ Total [223.58 GB] Free [14.44 GB]
230-| Drive:R:\ Total [372.62 GB] Free [152.99 GB]
230-| Drive:S:\ Total [372.62 GB] Free [254.64 GB]
230-| Drive:V:\ Total [152.66 GB] Free [26.25 GB]
230-| Drive:W:\ Total [372.62 GB] Free [101.34 GB]
230-| Drive:X:\ Total [372.62 GB] Free [1.01 GB]
230-| Drive:Z:\ Total [372.62 GB] Free [99.16 GB]

but it is nessessary -- but if i was using a DV camera , i would just keep it as DV throughout as i see no reason to convert it to uncompressed (or lossless codec) unless i was going to be up-rezing the DV to HD or film at some point.
JaysonHolovacs wrote on 7/14/2004, 10:31 PM
If you don't have 19 HDs, you will find uncompressed to be a bit large.

A additional downside of large file sizes I've noticed is lesser performance. You might think that not having to decode the video on the fly would make the performance better. Not true. At least in my case, my CPU has no trouble decoding real time MPEG, but my disk drive will choke trying to play back uncompressed AVI. If I use Windows Media Player to view my files, I get the best performance with no stuttering using MPEG rather than DV-AVI, and uncompressed is even worse. It's a pain when you are trying to check something that you've rendered and it keeps stuttering and hanging.

I'll usually use DV-AVI for all source and intermediate files, and render the final output to MPEG/AC-3 to go to DVD-A2. It may not be lossless, but DV seems very good with little generational loss. I did see the loss when I tested it with a specially designed pattern, but I don't render patterns, I render video, and I have no complaints there.

Of course, my point of view will be quite different from professionals that have lots of high speed RAID equipment, but that's my 2 cents.
Spot|DSE wrote on 7/14/2004, 10:36 PM
Going from DV to uncompressed media, and then going to yet another form of media is somewhat redundant and potentially problem-prospective because of all the transcodes.
Even with large RAIDS,etc, most of our work is either DV or DVPro, with a very little HDV from a JVC a client owns, or 4:2:2 HDCam stuff from Thomson. And most of the time, we dumb it down to DV for editing, and replace the media later.
kentwolf wrote on 7/15/2004, 4:21 AM
BJ_M:

Just out of curiouslty, what command line switch did you use to get your drive status like that?

I assumed you used a variation of command line "dir" and then piped it to a *.txt file.

I have but a lowly 9 fixed drives. I'd like to be able to make a drive stats txt file like you listed below.

Thanks!
B_JM wrote on 7/15/2004, 7:05 AM
i just logged into my ftp server running on my machine - which runs a script which gives this report (i use blackmoon ftp pro) ....

we use ftp to transfer between machines in our network which has sgi , linux , osx and win2k and winxp machines, as well as frame servers and HD servers -- it is the easy way and they all support FTP ..