DVCPRO HD - Storage & throughput requirements

R

Ron Marinelli

Member
I'm trying to budget for a video editing setup with a G5 dual 2.7, FCP HD 5.0, etc.

I searched through the posts but couldn't find any info or a link to determine what sort of storage requirements there are for DVCPRO HD a la the HVX200.

Something like how many GB/hour of footage for storage, and how much throughput is required to edit multiple streams.

Am I understanding it correctly that DVCPRO HD is a compressed format?

Any and all related info is appreciated.

Thanks.


Ron...
 
DVCPRO-HD storage depends on what mode and what frame rate you shoot in. The general numbers are:

1080: 1 minute per gigabyte
720/60: 1 minute per gigabyte
720/30: 2 minutes per gigabyte
720/24: 2.5 minutes per gigabyte

A full data stream is about 13 megabytes per second, and I believe both FCP-HD and Avid systems can handle at least a couple of streams in realtime.
 
fcp system requirements (hardware)

fcp system requirements (hardware)

i'm in a similar situation so i just got 1.5 terabytes for under $2000. assuming 1 meg per minute, i should be fine but what about capture/playback/render hardware? g5 and fast raid are a start but my g5 is choking on dv alone. are there any dvcprohd cards (mac friendly) that will accelerate the editing/rendering process. preferably something scalable from hdv up through dvcprohd. any recommendations?
 
"i'm in a similar situation so i just got 1.5 terabytes for under $2000. "

Was that for a SATA raid or Firewire? Is Firewire 800 fast enough for several HD streams, or should we just focus on SATA raids?
 
Firewire 800 is 100MB/sec and Sata is 150MB/sec. I went with the removable Sata drives and that works for me. Of course I haven't had a chance to do an HD on this system yet.
 
Firewire 800 is 800 Mbps. The problem of course is reading and writing that much data on both ends of the cable. Same thing goes for S-ATA of course - while the burst rate from cache is 150 MB/s = 1200 Mbps, the sustained rate is much lower... and since the caches are at most 16 MB each... that's not a lot of video. I don't see much point in buying hard drives for a 100 Mbps camera now. They'll be half the price by the time the camera comes out.

At any rate, my new S-ATA hard drives in RAID 0 are capable of transfering 480p60 uncompressed for smooth playback (tested with downconverted HDV of a hyperactive kitten) - that's 62 MB/s = 480 Mbps. Couldn't get 720p60 uncompressed though - which isn't much of a surprise at 1327 Mbps.
 
sata raid

sata raid

Ron Marinelli said:
"i'm in a similar situation so i just got 1.5 terabytes for under $2000. "

Was that for a SATA raid or Firewire? Is Firewire 800 fast enough for several HD streams, or should we just focus on SATA raids?
Click to expand...

i have an sata raid comprised of four 400gb hitachi 7200rpm drives in a granite digital raid enclosure powered by a sonnet pci sata with 8 external sata ports.

if you're doing anything more than just capture, i would recommend an sata raid instead of firewire. besides the spec difference of fw800's 100mb and sata 150mb, there are major overhead issues with the firewire bus on a g5. check out www.barefeats.com for details on g5 problems with firewire. and if you're doing any rendering with hd, you'll need all the speed you can get. not sure how many streams of hd an sata raid will handle but i will let you know if i get the hvx200.
 
Okay, lets clarify this once and for all.......HVX uses DVCPRO HD, and does not require anything more than a Firewire 400 interface and a 7200RPM drive. Uncompressed HD, 10bit, 4:4:4 or 4:2:2 is a different matter. But you are not going to be working with this higher format of HD from the HVX.

And yes DVCPRO HD is compressed.
 
wigby said:
if you're doing anything more than just capture, i would recommend an sata raid instead of firewire. besides the spec difference of fw800's 100mb and sata 150mb, there are major overhead issues with the firewire bus on a g5. check out www.barefeats.com for details on g5 problems with firewire. and if you're doing any rendering with hd, you'll need all the speed you can get. not sure how many streams of hd an sata raid will handle but i will let you know if i get the hvx200.
Click to expand...

I am confused. Firewire is a communications format, not a disk-writing format, correct? For almost every application I can think of, FW800 itself is no bottleneck--drive speed on the end of the FW cable is. Even FW400 is sufficient to handling 100mb/s DVCPRO100. The problems lie squarely with how fast the drives themselves can read or write the data, not the pipeline. I would think FW800 could handle at least two or three simultaneous DVCPRO100 streams without a hiccup. Finding drives that could keep up, however, is an entirely different matter.

For a huge HD project, a giant RAID array hooked into perhaps two or three FW800 buses might be in order. As stated earlier, a G4 Powerbook is actually SUPERIOR to the fastest G5 tower with regard to FW800 read/write speeds, for inexplicable reasons. My Powerbook has a CardBus FW800 adapter as well as the built-in FW800 port, so I have two completely discreet FW800 buses to saturate with data. I'd need something on the order of 5-drive RAID arrays on EACH BUS to choke both of the FW800 communications links.

Am I missing something here? I use Seagate Barracuda 8MB/200GB SATA drives because they're reliable and cheap. Whether I use them in a hardware SATA array or with FW800 enclosures, they can only read/write at their max specs (and progressively slower as they fill up). Do PATA drives themselves read/write at higher specs than their SATA versions?
 
DVC PRO HD in both 720 and 1080 flavors is gonna' be 13MB per second. The bearfeats tests indicate the sustained read/write throughput of firewire 800 on a G5 to be about 45MB per second in single stream (1 Cable). This should give you a minimum of 3 simultanious streams of HD video. They also clocked the read time at closer to 75MB per second so if any of your streams are viewing only you could get as many as 5 going on firewire 800. This seems very reasonable for most applications. I have shot 5 camera shoots before but never in a situation where I had to cut them myself. Three streams gives you most everything you would need.
 
nobody is talking about capture rates

nobody is talking about capture rates

fiercecurry said:
Okay, lets clarify this once and for all.......HVX uses DVCPRO HD, and does not require anything more than a Firewire 400 interface and a 7200RPM drive. Uncompressed HD, 10bit, 4:4:4 or 4:2:2 is a different matter. But you are not going to be working with this higher format of HD from the HVX.

And yes DVCPRO HD is compressed.
Click to expand...

the post began with questions about pc specs and requirements-not capturing from the cam. some people want/need more than the fw800 bus can deliver. sure faster drives help but a faster bus (sata) will allow for quicker processing and transfer of hd data streams - especially uncompressed. i know dvcprohd is compressed but that doesn't mean it has to stay that way in post.
 
wigby said:
what about capture/playback/render hardware? .are there any dvcprohd cards (mac friendly) that will accelerate the editing/rendering process. preferably something scalable from hdv up through dvcprohd. any recommendations?
Click to expand...

I'm wondering the same thing..are there any capture cards out there now from Pinnacle or Canopus or Matrox that render DVCPRO HD in real time for the PC or Mac?
 
You don't capture DVCProHD files on a Mac. You copy the MXF files to your HD and save them as QT files. Period. As for rendering on a Mac: No need for a render card...
Final Cut Pro 5 can handle DVCProHD in real time during editing, even quite a bunch of effects and such things. Up to five parallel streams. I'll have FCP5 next Friday and check it out. See no reason why they should tell us lies.
 
Blonde,

seems to be even better. See Barry Greens message from today 11:11 AM at the
"Recording from Firewire" thread.
 
g5 render times

g5 render times

PKraft said:
You don't capture DVCProHD files on a Mac. You copy the MXF files to your HD and save them as QT files. Period. As for rendering on a Mac: No need for a render card...
Final Cut Pro 5 can handle DVCProHD in real time during editing, even quite a bunch of effects and such things. Up to five parallel streams. I'll have FCP5 next Friday and check it out. See no reason why they should tell us lies.
Click to expand...

i find that hard to believe that any current g5 will handle hd streams in realtime. my g5 needs to render dv with almost every effect i apply. now add 6x the resolution, 4 times the data rate and a few simultaneous streams and you're telling me 2.5ghz g5 won't choke without 3rd party hardware acceleration?
 
Wigby,
that's the way it is. Some effects are realtime, some are not. Which ones qualify for realtime depends on your installed RAM memory and your graphics board. There are better ones and cheaper ones. And it depends on available video memory. The more the better for realtime editing.

You can't say "I have a G5 and that will do." You have to tweak the whole system to boost and optimize its performance. Wouldn't try DVCProHD under 2 gigs of RAM and with a videocard with less then 128 GB of video memory. So a Powerbook 1.67 GHz with 2 gigs of RAM and an ATI 9700/128 GB is a save bet. Not to forget the hard drive - 5400 at least, 7200 better.
 
PKraft said:
and with a videocard with less then 128 GB of video memory. So a Powerbook 1.67 GHz with 2 gigs of RAM and an ATI 9700/128 GB is a save bet.
Click to expand...


..wow 128GB of memory on a graphics card.. where have i been? lol i think he means MB :beer:
 
You must log in or register to reply here.
Back
Top