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View Full Version : Uncompressed video and video arrays.



Tom Wood
03-14-2003, 06:25 PM
Hi,

I'll be creating my scenes in Lightwave and want to maintain the highest possible quality of image through the production process, which ends at a DVD. I like the idea of keeping the video uncompressed through editing, but I am concerned about file size and disk space. Since Newtek recommends SCSI drives for VT, disk space gets expensive when compared to IDE. Is my desire to work on uncompressed video not valid since it ends up being compressed at the end? If not, how large a pair of SCSI drives would I need to comfortably produce and edit about 45 minutes of 3D animation?

Thanks,

TW

vip3dran
03-14-2003, 07:04 PM
Tom,

Know where you're coming from regarding the higher costs of SCSI drives.

We have found a workable solution with IDE drives using a 3ware Escalade controller. It shows up as a SCSI device in windows and depending on the model you look at, can handle 4, 8 or 12 drives with amazing speeds when the 4+ drives are set-up as a RAID. There is one ribbon cable per drive and each drive is set as master.

If you want to look into it further, check here: www.3ware.com

mgrusin
03-16-2003, 10:45 AM
Uncompressed video takes something like 80GB / hour. You'll want somewhat more storage than your final length of 0:45; most people would say twice or three times that, but since you're animating, most of the outtakes etc. will be taken care of before you render (but save some for the closing credits ;)) The Toaster will also want some space for its background cache; I'm seeing it use ~10GB cache for each hour of project, but I'm using lots of transitions so that may be more than average.

Uncompressed is always the goal for painless maximum image quality. But you could certainly consider using compression to get more video out of your drives. DV format only takes 12GB/hour, and there are lossless formats like huffyuv as well (http://math.berkeley.edu/~benrg/huffyuv.html). A side benefit is that if you compress your video, your drives don't have to run as fast as they would for uncompressed. This roughly translates into being able to use slower (cheaper) drives, or packing more simultaneous streams onto faster drives. The important tradeoff is that compressed streams need to be uncompressed in realtime by your CPU(s); it shifts the burden from your storage to your processor(s). So you may want a faster machine to take advantage of this.

Another thing to check is to make sure that you can get your selected format (compressed or uncompressed) into whichever DVD-building tool you're planning on using. This currently includes rendering out your entire final project to a new single file (which will take that much more disk space), or you could wait a few months until T3 comes out, which will include a "wrapper" function which will eliminate this final render requirement.

I personally use a relatively slow IDE array (non-Escalade) and DV compression on a single P4 @ 2.4GHz. My situation is different from yours in that I am editing 5+ hour projects, and it only needs to be output to VHS so the quality reduction isn't noticeable. But it works great for me. Your mileage will (and should!) vary; the cool thing about the Toaster is that it's this flexible.

Hope this helps, good luck on your project! -MG

Tom Wood
03-16-2003, 05:27 PM
Thanks vip3dran, I'll look into that.

Thanks MG, one other quick question if I may. Does it matter to the storage capacity if the video is rendered in fields rather than frames?

I visited http://www.medea.com/ and looked at their storage capacity charts. I assume the 1080 columns are for film and HD, and the 1:1 is uncompressed?

TW

Danner
03-17-2003, 06:08 AM
Field rendered or frame rendered footage takes the same amout of HD space, around 22mb per second.

Alpha channel enabled RTVs do make the size go up a bit ( or 8bit? heh)

Sometimes for my final composition I use Morgan Mjpeg compressor at about 6mb per second at 94 quality. it compresses in real time to a fast drive or array and looks amazing. (amazing that is after I turned off SSE2 on the codecīs compression panel.. took me a while to figure that one out)

Iīve read others use Manconcept or PictVideo codecs with equal succes.