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View Full Version : Sd, Hd, Hdv, Oh My



JCVR
10-10-2005, 11:17 PM
so, for the time being i'm satisfied with the SD quality image of my DVX ( that is until I look at the huge pictures my digicam can snap). I understand it records HD, is that uncompressed? Does the HVX bypass this whole HDV fiasco that seems to be going on? are they even including the option for it.... doesn't seem so. What is the general reaction to this, are all of you happy with SD to tape and HD to drive or P2 being the only options?

Landon D. Parks
10-11-2005, 12:22 AM
The HVX records in DVCPRO HD (among DVC 25 and 50), It uses DVCPRO HD, 50 and 25 Codecs, Its not the same as HDV, as HDV records an HD image onto a 25Mbps MiniDV tape in a extremly compressed (correct me if I'm wrong, MPEG compression). In DVCPRO HD mode, this camera (HVX) will record 100Mbps DVCPRO HD to the P2 cards.

So in a sense, no, It's not like HDV, It's not even in the same ball park in my opinion...
To my knowing, the camera has no HDV option, and why should it?

Haakon
10-11-2005, 02:19 AM
To my knowing, the camera has no HDV option, and why should it?No, it doesn't. Nothing even remotely close.

Landon D. Parks
10-11-2005, 02:37 AM
Plus, it also has an HDSDI output, so really if you wanted to you could record the camera footage directly to your computer, considering you have enough computer power to stream HDSDI footage into it. HDSDI is like 10-bit, uncompressed... So, Well, you get the picture.

You will need a $1,000 HDSDI input card, but if your have the money to edit HDSDI footage, then $1,000 is not a whole lot.

I'm considering shooting my next film on the HVX200... I will probly follow this workflow if we use the camera: Shoot it, record it 1080 24p to a 8GB P2 card, one P2 Card #1 is full (Probly 2 or 3 takes in), we will swop card 1, for card #2 (also 8GB), and while card one is being logged to a harddrive or the computer, we shoot on card 2... Then by the time card 2 is full, card one should be ready to go again... so in a since, we should not need to stop shooting to unload the cards...

I am also toying with the idea of using the camera HDSDI port to record the footage directly from the camera to an on-set hard disk array (smilare to shooting with a Viper Filmstream), but this is TBD.

eLeventy
10-11-2005, 03:23 AM
Plus, it also has an HDSDI output, ....

Nope, sorry, it doesn't.

Jan_Crittenden
10-11-2005, 04:28 AM
Hi,

That is true, it does not have HD-SDI, but you could use one of the Miranda or AJA boxes that will translate it from Analog component to HD-SDI.

Hope that helps,

jan

Landon D. Parks
10-11-2005, 05:45 AM
I thought I read somewear it had HDSDI?? Oh well, not a big deal... Firewire can transport more than 100MBPS anyway, so Firewire is always a P2-Free option, but personally, I'm more "Into" the idea of P2 cards anyway, which will prolly be my first choice as a capture format.

The workflow I would follow with P2 MFX anyway is unload the MFX files from the card to an on-set Laptop (via the laptops by the PSMCIA slot), then at the end of the day, dump the files from the laptop via a network (CAT5) onto my dream editing MAC, then edit it there... Seems straightforward to me.

Haakon
10-11-2005, 05:55 AM
What is the datarate of the uncompressed coming out of the XL H1's HDSDI port? 1.4 Gbps or something ridiculous like that?

"Uncompressed" is a lovely pipe dream, but you'd never be able to get enough power to edit it or space to store it. Which leaves the camera with nothing but uber compressed HDV.

I'll take my DVCPROHD, thanks.

fiercecurry
10-11-2005, 01:45 PM
"Uncompressed" is a lovely pipe dream, but you'd never be able to get enough power to edit it or space to store it.

How is it a pipe dream? There are HD video cards, which go for $600, and 1.5 TB RAID drives that go for $1500. So for around $2100 plus your computer (which I imagine most of us have already) you are capturing and editing in HD. As for power, you just need an electrical outlet, or plug into the generator used to power the lights on set.

How much are those p2 cards?

Barry_Green
10-11-2005, 02:01 PM
and 1.5 TB RAID drives that go for $1500.
What 1.5 terrabyte RAID for $1500 are you referring to?

As an example, I looked up the G-Tech G-RAID; 1 terabyte for $1199. It is *nowhere near* fast enough to handle HD-SDI data rates. It's barely fast enough to handle a single stream of standard-def SDI. For high-def SDI you'd have to RAID six of those RAIDs together!

And that would be straining, to give you ONE STREAM. If you want to edit multiple streams, you'd need probably 18 of those G-RAIDs, all RAIDed together.

The Firewire 800 connection they use, at 100% saturation, could barely handle HALF the data rate of HD-SDI. So you'd have to have some sort of controller that could RAID together FW800 buses.

Ain't cheap.

Don't underestimate what a staggering task it is for today's hardware to handle uncompressed HD-SDI. It is, as was said before, a "pipe dream".

contentlab
10-11-2005, 02:13 PM
Don't underestimate what a staggering task it is for today's hardware to handle uncompressed HD-SDI. It is, as was said before, a "pipe dream".

there should be some sort of definition of "uncompressed" stated here.

are we talking HD-SDI from a D5 deck at 4:2:2 colorspace?
are we talking about dual-link HD-SDI 4:4:4 from top of the line Cinealta?

i'm asking because i'm also rather confused. i thought my decklink dual-xeon system, 4GB RAM with 2TB SATA raid was doing uncompressed, 8 & 10bit. single link HD-SDI only though. but now i'm lost...

i guess the ultimate question is where do you get TRUEuncompressed HD from and what kind of compression is normally seen?

mmm
10-11-2005, 02:28 PM
Uncompressed presents more of a problem for the hard drives because of high datarate than the processor. I am not sure exactly how uncompressed compares with something like HDV when it comes to processor strain, but I guess it would actually be LOWER because the footage does not need decoding for use - Barry?

The best uses for the HDSDI output on th XL H1 is live mixing or direct capture using a high quality codec or something like a HDCAM deck. However, by the time you hire a deck, why not just hire a 2/3" HD camera.

braw
10-11-2005, 02:32 PM
Here's what I found on hdforindies.com

HDV - (less than DV, which is 3.5 MB/sec) - 1280x720p30 - I think something like 2.5 MB/sec

DVCPRO HD for 720p24 8 bit 4:2:2- 1280x720 (really 960x720 stretched) - 5.4 MB/sec

DVCPRO HD for 720p30 8 bit 4:2:2- 1280x720 (really 960x720 stretched) - 6.75 MB/sec

DVCPRO HD for 1080i60 8 bit 4:2:2- 1920x1080 (really 1280x1080 stretched) - about 14 MB/sec

Uncompressed 720p24 8 bit 4:2:2- 1280x720 - 42.3 MB/sec

Uncompressed 720p30 8 bit 4:2:2- 1280x720 - 52.8 MB/sec

Uncompressed 720p60 8 bit 4:2:2- 1280x720 - 105.5 MB/sec (this one I confirmed from FCP captured data)

Uncompressed 720p24 10 bit 4:2:2- 1280x720 - 52.8 MB/sec

Uncompressed 720p30 10 bit 4:2:2- 1280x720 - 66 MB/sec

Uncompressed 720p60 10 bit 4:2:2- 1280x720 - 132 MB/sec

Uncompressed 720p24 8 bit 4:4:4- 1280x720 -63.4 MB/sec

Uncompressed 720p30 8 bit 4:4:4- 1280x720 - 79.2 MB/sec

Uncompressed 720p60 8 bit 4:4:4- 1280x720 - 158.4 MB/sec

Uncompressed 720p24 10 bit 4:4:4- 1280x720 - 79.2 MB/sec

Uncompressed 720p30 10 bit 4:4:4- 1280x720 - 99 MB/sec

Uncompressed 720p60 10 bit 4:4:4- 1280x720 - 198 MB/sec

Uncompressed 1920x1080p24 8 bit 4:2:2- 95 MB/sec

Uncompressed 1920x1080p30/i60 8 bit 4:2:2- 118.6 MB/sec

Uncompressed 1920x1080p24 10 bit 4:2:2- 118.6 MB/sec

Uncompressed 1920x1080p30/i60 10 bit 4:2:2- 148.3 MB/sec

Uncompressed 1920x1080p24 8 bit 4:4:4- 142.3 MB/sec

Uncompressed 1920x1080p30/i60 8 bit 4:4:4- 177.9 MB/sec

Uncompressed 1920x1080p24 10 bit 4:4:4- 177.9 MB/sec

Uncompressed 1920x1080p30/i60 10 bit 4:4:4- 222.4 MB/sec

Uncompressed 2048x1080 12 bit 4:4:4 (the maximum possible dual link HD-SDI frame size and bit depth, SMPTE 372M) - 227.9 MB/sec

True 2K film scan - 2048x1536 10 bit log, 4:4:4: 270 MB/sec

True 4K film scan - 4096x3072 10 bit log 4:4:4: 1080 MB/sec, aka 1.055 GB/sec

Barry_Green
10-11-2005, 03:23 PM
are we talking HD-SDI from a D5 deck at 4:2:2 colorspace?
No, we're talking about 1920x1080, 4:2:2 single-link HD-SDI from the Canon XL H1 camera head. The data rate is 1.45gigabits per second per second for a single stream, and that's video only, no audio is carried on the Canon's output.

Jim Arthurs
10-11-2005, 03:27 PM
Don't underestimate what a staggering task it is for today's hardware to handle uncompressed HD-SDI. It is, as was said before, a "pipe dream".

Hi Barry... I guess I own the stuff dreams are made of then. :) You're correct that there is MUCH talk about doing live HD-SDI capture on the message boards and very little actual capture happening. I'm an exception to that, as I've done lots of virtual set work with live cameras feeding my NLE, and I'm glad to share the details of my storage.

I want to point out that it's entirely possible to build inexpensive internal RAIDS. Here's what I have for uncompressed HD editing, as profiled in an article I was interviewed for in Feb's POST mag;

I took 4 250gig Western Digital SATA drives hooked to a HighPoint Rocket Raid 1820a controller in RAID 0 and stuffed the hole lot into my tower case. This combo cost barely 800 bucks a good 14 months or so ago. Starting over today, I could put in 4 400gig drives for about the same money giving 1.6 terrabytes.

The specs? When half full I can still read 220 MB/sec and write 200 MB/sec. I use this home-brew RAID to power my Leitch VelocityHD boardset. Uncompressed (single stream) 10 or 8bit 1080i is absolutely no problem for this setup, and it will choke through dual stream uncompressed dissolves well enough to let you see what's going on. Two streams of 60 MB/sec compressed HD is butter smooth.

Now this particular RAID card requires PCI-X slots, which aren't seen often on PC motherboards unless they are server grade boards. The solution is either to use PCI-E controller cards (which are just starting to show up) or take advantage of the RAID features that most newer MOBO's are offering for SATA drives.

My Altitude card is expensive and requires an expensive MOBO with PCI-X slots, but the upcoming PCI-E Decklink cards put into a system with on-board SATA RAID should work for uncompressed HD capture/ingest and not break the bank doing it.

My two cents,

Jim Arthurs

Haakon
10-11-2005, 07:14 PM
Cool! You managed to edit together your 4 terabyte home movie! Now where are you going to put it? :undecided

This is the exact same argument that the anti-P2 folk keep barking at Panasonic; "how are you going to archive your P2 footage?" The obvious difference here is that 1GB per minute DVCPROHD is actually managable in a myriad of ways whereas 1.45gbps uncompressed HD is not. That's all I'm saying.

Jim Arthurs
10-11-2005, 07:33 PM
There is no practical archiving of this kind of footage. When done with a project I lay off to tape whatever is needed, save off the greenscreen footage as .png sequences and ditch the rest. Which, to be honest, is more or less how I worked in SD for many years.

The irony is that HD NLE's progressed BACKWARDS from the way SD NLE's evolved... HD NLE started out with uncompressed only (save the various versions of Sony's) and only lately has offered various compression schemes beyond the raw camera codecs (Avid's new codec, Leitch's wavelet, Matrox's, Canopus, etc.)

I look forward to using DVCPRO 100/50, as my hardware will allow those native formats to playback realtime without conversion. Right now I have support for P2 originated DVCPRO 50, though I haven't had access to a file to experiment with yet.

Regards,

Jim Arthurs

fiercecurry
10-12-2005, 01:23 AM
What 1.5 terrabyte RAID for $1500 are you referring to?

It is, as was said before, a "pipe dream".

Okay, here it is, i was off by $500 and 25GB. Wake up pipe dreamers:

http://www.lacie.com/products/product.htm?pid=10456

Barry_Green
10-12-2005, 01:39 AM
Wow. Interesting. On a Mac it's almost fast enough to support a single stream of around 100 minutes... I didn't think they had it to that degree yet.

Not without its issues though; you only get the fastest speed at RAID 0, which means you've got four times as much exposure to losing your data as any single drive by itself, and I don't know if 187MB/sec is quite enough to handle the full HD-SDI signal and all overhead necessary... plus, again, that's only a single stream. And you only get that speed on a Mac; the Windows platform is limited to 160mB/sec; don't know if that'd be fast enough either.

Good find though -- that's a lot of really fast storage for a relatively little price! Shouldn't be long before a desktop/tower RAID is a reasonable solution for recording the full-data-rate HD-SDI feed from the XL H1!

fiercecurry
10-12-2005, 02:01 AM
If its 187MB/sec on a MAC and 160MB/sec on PC, at 3GB/s it can handle this quite easily:

Uncompressed 1920x1080p24 10 bit 4:2:2- 118.6 MB/sec

Uncompressed 1920x1080p30/i60 10 bit 4:2:2- 148.3 MB/sec

fiercecurry
10-12-2005, 03:41 AM
This may be overkill for what most people, but it puts into perspective what one can do with
a RAID and a computer hooked up to an HD-SDI output,

http://www.hdforindies.com/2005/02/uncompressed-direct-to-x-serve-raid

contentlab
10-12-2005, 01:47 PM
Wow. Interesting. On a Mac it's almost fast enough to support a single stream of around 100 minutes... I didn't think they had it to that degree yet.

Not without its issues though; you only get the fastest speed at RAID 0, which means you've got four times as much exposure to losing your data as any single drive by itself, and I don't know if 187MB/sec is quite enough to handle the full HD-SDI signal and all overhead necessary... plus, again, that's only a single stream. And you only get that speed on a Mac; the Windows platform is limited to 160mB/sec; don't know if that'd be fast enough either.


again i'm confused. what do you mean the Windows platform is limited to 160MB/sec when i'm seeing 376MB/s reads and 328MB/s writes on my dual Pentium Xeon system using a Deckling HD Pro Single Link card with a 2TB Promax SATA raid with 8 250GB drives. below is a screen capture of the Blackmagic Disk Speed test. i'm using close to 700GB of drive space and disk fragmentation analysis says that i've got 42% total fragmentation with 84% file fragmentation.

my point is, it seems as if HD-SDI uncompressed capture is here and "somewhat" affordable. My dual processor system and 2TB Raid with Adobe Video collection software suite cost my company a mere $12k :)

http://static.flickr.com/29/51932374_a56dfe1186_m.jpg