Canon XLH1 does uncompressed 1080i 4:2:2 over HD-SDI

[Chris Hurd]

Originally Posted by Martin von Will

Is the HD-SDI output 8bit, 10 bit or 12 bit 4:2:2 ?

Canon is not stating the bit rate of the SDI output.

[Jacques Mersereau]

I am just hoping Canon is using a higher bit count for
camera processing than 8 bit ala the XL1.
Unfortunately, I would have wager that the HD1 is (only) 8 bit out.

I am GLAD to be prove wrong however :)

[A. J. deLange]

It will definitely be putting out 10 bits because that's what the standard calls for but the 2 LSB's will probably be 0's! I did stumble across a German site (couldn't find it again) that authoritatively stated that it's 8 bit output but that's just another rumor at this point as far as I'm concerned.

[Martin von Will]

Is there a way to actually find out? Canon refuses to release that info?
What do some of the rental houses know?

[A. J. deLange]

Originally Posted by Martin von Will

Is there a way to actually find out? Canon refuses to release that info?
What do some of the rental houses know?

Once someone has captured some data from the interface there are various ways to tell. It should be obvious on a histogram, for example. Guess we'll have to wait until the things hit the street to know for sure.

[Luis Caffesse]

My guess would be to expect 8 bit. Just seems that if it was a 10bit output Canon would be listing that, seeing as they're pushing the SDI output as "THE" feature on this camera (and rightfully so).

But, time will tell for certain.

[Steve Crisdale]

I thought Kaku Ito posted some HD-SDI captures that he'd done...

Did anyone download them and see what the colour bit co-efficient was?

I'd have bet that Canon would maintain a bit co-efficient close to the DVD standard.

Anyone know the bit co-efficient for HD broadcast ts? It might give a clue, considering Canon would be looking to compete with the Z1 as a low-cost studio HD camcorder.

[Guy Cochran]

Maybe this is the holy grail, the Doremi Labs V1-UHD. It's an HD-SDI direct to disk recorder capable uncompressed or compressed . Now if they could just shrink it down and make it cost 1/10 of the price :)

http://www.findarticles.com/p/articl...9/ai_114928357

http://www.doremilabs.com/products/producthd.htm

[Eric Brown]

40k. Ouch.

[Thomas Smet]

The one advantage for me to getting the XLH1 was the SDI port. I was going to get the Decklink multibridge that had component HD in as well as analog audio for all the other HD cameras. Now that the Canaon has SDI I could just get the $500 HD dEcklink card. The only problem is the lack of audio out on the SDI port. The current Decklink HD cards only take in AES or Spdif audio.

Does anybody know of a cheap way to convert analog audio to AES or Spdif digital audio so I can import through a Decklink card. If this is going to be too dificult I may still have to get the Multibridge. Or I guess I could record a HDV tape as well and then resync the audio from the hdv tape to the uncompressed version on my system. That seems like a huge pain however.

[Gary McClurg]

That's a question I was thinking myself... on the Waifan (not sure if bad spelling) can you record to tape as well...

Always nice to have a back up...

[David Newman]

Gary,
Recording via HD-SDI into the Wafian box doesn't disable the tape mechanism within the camera - so you can easily use the tape as another backup.

[Frank Farago]

Well, for "field" recordings, one would need an HD DeckLink card that can be inputted to a notebook computer, via PCI-X16. I am not sure if BlackMagic Design makes a PCI-X version of their HD capture cards yet.

If they do, the best notebook that will TRY to keep up with this mass data input would be something like the ALIENWARE Area-51 series notebook... Say, two 120 GB SATA drives spinning at a respectable 7,200 RPM and linked as a RAID 0 array. I am not too good at math, but you should be able to capture X minutes of HD-grade uncompressed video onto 200 or 240 Gigs, if you have little else on the drives.

Otherwise, one can get a SPF or other desktop edition PC onto the set, especially if it is interior, then use AC power, a gennie, or a DC-to-AC power inverter to run it. Get the best quality (thickest) coaxial cable you can get for an SDI tro SDI connection. In this case, I would you the 10K spin rate SATAs or SCSI drives.

I am not sure if DV RACK can record true uncompressed 1920 x 1080 HD signals, though... I think they top out at HDV's 1440 x 1080i compressed.

However, the most assured way to capture the uncompressed HD signal out of the Canon would be to go HD SDI OUT to HD SDI IN of a 1/2-inch portable Sony HDCAM field recorder. Based on current prices... you will be able to purchase one Canon XL H1 camcorder PLUS a true high-def 1/2-inch HDCAM field recorder VTR for less money than Sony charges for one of their CineAlta camcorders. It won't be progressive, but HDCAM is interlaced, anyhow.

Worth pondering a tad.

[Alister Chapman]

You are unlikely to get any sort of laptop HD-SDi option in the near future. Two SATA drives won't have the bandwidth for 1080i HD uncompressed. You need at least 4 SATA drives, ideally 6 or 8 in RAID 0 controlled bycontroller card using 64 bit 13Mhz PCI-Express controller. 66Mhz or 33Mhz PCI is not fast enough.

You could build a PC with an internal 6 or 8 drive array, a declink card and a dual core CPU. That's what I am doing. Obviously mains power, a generator or a large inverter will be needed to power it, but for most drama shoots mains power is available.

I intend to use a Phillips 17inch HD TV as both the computer monitor and as on set monitor.

I would expect to see more Wafian style devices over the next couple of years. HDV, CINEFORM, DVCPRO HD and HDCAM all have thier uses but the holy grail of HD is uncompressed, and it isn't really all that expensive to put together a PC (or Mac) with the ability to capture uncompressed HD. Storage is getting cheaper and cheaper so big disk arrays don't need to cost the 10's of thousands of dollars they used to cost when you were limited to complexed arrays 9Gb SCSI drives!

[Frank Farago]

Originally Posted by Alister Chapman

You need... RAID 0 controlled by controller card using 64 bit 13Mhz PCI-Express controller. 66Mhz or 33Mhz PCI is not fast enough.

Agreed, for the most part. Alister, did you mean to say "133 MHz PCI-Express controller card" in your sentence above, perhaps?

Indeed, it is rather "easy" to build a state-of-the-art editing PC these days. Did you mean a dual processor motherboard with both CPUs being (Intel?) dual-core type, or a single CPU with dual-core?

I completely agree with you in not trying to cram EVERYTHING into a notebook PC. On most location shoots, you will have either a large or small gennie, or at last you can take with you a stack of 12-volt car or truck batteries and do the power inversion from them to 120 or 240 Volt AC. Having these little designer batteries costing hundreds of dollars a pop, and then having their chargers also costing hundreds of bucks is just crazy.

With respect to the "Phillips 17-inch HD-SDI monitor" that you will be using, I am no familair with this one. But I did see in action the new Panny 17-inch HD-SDI studio/field/editing monitor, and it blew me away! Comes with all sorts of interfaces standard (SDI, HD-SDSI, etc.), has a built-in power supply, and can even be powered from battery via an XLR connector! In my view, and certainly bang for the buck, it blows Sony's Luma line outta the water.

The Panny rep told me that after this 17-incher, they will have other, larger screen size units as well in this new pro line. (Panny BT-LH1700W). I was wondering, what the model number of the Phillips monitor is and how these two campare in price? The Panny you can get for about $2,800. Again, everything is built-in already, unlkike with anything you'd be getting from Sony.

Lastly, yes, the Canon XL-H1 indeed does uncompressed 1080i 4:2:2 over HD-SDI. But... why would you ever need this?

Our last projct we shot on film and delivered in SD on Digital Betecam PAL, also "downconverted" to D-Beta NTSC. The next one will also be shot on film, and delivered on HDCAM. Both projects are for network broadcast. The PAL territories still stick with D-Beta PAL as deliverables, while in the U.S., HDCAM is a widely acepted format, as you know.

Now, both D-Beta and HDCAM are compressed formats. With HDCAM, you have about 154 MB/sec transfer rate. The Canon XL-H1 would output signal uncomressed at about ten-times this huge data rate, at app. 1,500 MB/sec. I think this data rate is not only astronomical and largely unsupportable, but not even needed.

There is nothing really wrong with data rate compression, if out of five billion humans, maybe one or two can identify that a codec was even employed. Even the Sony HDCAM-SR pales in comparison to the wholly unomressed data channel requirement you would need to configure to record and play back 1.5 GB/sec of video-only data to/from hard drives.

The one place I could see this would be for archiving of material for posterity, so in 100 years or so, a "copy" can be struck at 16K or 32K rez. But for that, probably the 1/3-inch XL-H1 is not the ideal source of acquisition.

I would love to use the XL-H1 for direct-to-hard drive recording, but only if this can be done at a data rate less than full 1.5 GB/sec. Do you suppose this is posible, i.e. can the "uncompressed HD-SDI OUT" signal from the Canon be compressed somewhat? If not, it will have to go to the mini tape for us, I'm afraid. BTW, we plan on using the HDV camera for the following apps: location scouting & test shoots, audion tapes, framing/chroma key positiong tests, "making of feature" documentaries, news clips, and cast/crew interviews, for eventual inclusion in the DVD version.