HDV Editing!
HDV is the new kid on the digital video editing block, promising to provide high-def capabilities at prices we associate with the prosumer world. The consumer HD dam was initially breached by JVC with its GR-HD1 camcorder, the first consumer level unit to incorporate the new HDV standard.

While early adopters loved having an affordable HD camcorder to shoot with, most soon figured out that without a complete editing and post-production solution, the initial HDV offering was little more than a curiosity. Still, anyone who watches the industry could predict that once the consumer HD cat was out of the bag, it wouldn't be long before more companies would step up and deliver real-world HDV editing products.

Welcome to that future. For the first time in history, it's now possible to assemble an affordable high-definition editing system based on the new HDV format.

The Shake-up

The first idea to wrap your brain around is that HDV isn't just a single standard as we're used to in the current world of regular DV.

DV — whether it's Mini DV, DVCAM, or even DVCPRO 25 — has been a single standard for a digital video data stream. The data contains one video stream plus two audio streams that always runs at 25 megabits per second and the stream is always compressed in the same fashion. That results in DV always being DV, as far as your editing computer is concerned (so long as it's not a professional format based on DV50, that is).

The HDV specification, however, provides for variations. One "sub-spec" of the HDV standard which JVC chose to implement on its GR-HD1 specifies an image frame constructed of 720 progressive lines of video. When Sony recently released its HDR-FX1 HDV model, they elected to use a different part of the HDV "standard"-1080 interlaced lines. So HDV isn't just one thing.

In practical terms, however, since all manufacturers were aware that both specs were possible, most HDV gear should handle either or both with aplomb. I said should. Actual cross-manufacturer compatibility of tapes shot in each format playing back on deck transports designed for the other will take more time to sort out. But whichever format you adopt, the good news is that hardware manufacturers should have a clear incentive to "play nice" with both.

The High Def Flow

High Def, of course, has been the "buzz du jour" of video production for quite a few years now. The problem for the rest of us — particularly those of us who want to shoot and edit our own stuff, is that in order to play the High Def game, we had to get our hot little hands on gear that was outrageously expensive.

Enter those clever engineers who are always tempting us with more bang for our video shooting and editing bucks. What's been mostly missing is a way to move this new HDV data stream around an edit suite for editing, compositing, titling and all the other production tasks we take for granted with DV. That's primarily because no matter how you slice, dice or compress it, any HD data stream, including HDV, is big. Very big.

And to give us products that do the things with HDV that we already do with DV, there had to be some new data reduction techniques developed.

Welcome to GOP

The key technical advance that makes HDV viable is that instead of treating each frame of video as a single element, HDV "packets" adjacent frames into a GOP, or group of pictures, then applies compression to the GOP rather than each frame of video.

It's a much more efficient form of compression since in most typical video content, there's not that much change that happens between adjacent frames. So, for example, frame 515 is packaged with perhaps a dozen frames on each side and the software samples all the data of one single frame in the group (the "key" frame) and then simply notes the changes that take place in the surrounding frames. Now for compressing a video stream this is very cool. It shrinks the data stream very efficiently.

But when it comes to editing, it's a whole 'nother ballgame. Because what if the precise place you want to place your "cut" is somewhere between two of those key frames and only the "difference data" is available? Big problem.

Software engineers looked at the situation and realized that in order to facilitate editing with the HDV streams, they'd need a way to decompress and re-compress the HDV stream "on the fly" in order to achieve both the smaller data flow they wanted and the editing capabilities that their customers demand. So the basic HDV reality is that there's a lot of computer crunching "under the hood" if you want to edit in HDV. Amazingly, today's modern desktop computers and software designers are so capable that they've actually developed ways to do this. And those solutions are finally coming to market from quite a few companies.

The Rescue Team Arrives

So what do the hardware and software companies have in the wings to rescue us from the current SD world and set us down safely in HD land — or at least HDV land?

As it turns out, a lot, so long as you're willing and financially able to equip yourself properly. Clearly, HDV editing isn't a task well suited for a years-old modestly powered computer. You need computing horsepower to spare. You'll also need a software package that runs on your hardware that's capable of HDV editing.

Some of the more popular software vendors are already touting their packages as "HDV ready." Typically, this means the software package is scalable. Scalable is just a fancy term for the software not really caring how big the incoming data stream will be. It's the opposite of software that expects a fixed size data stream. If the software package you use has the term DV in its title, it could be that it was designed for a DV-sized data stream only and isn't scalable up to HDV resolution.

The solution is to find alternate software that specifically touts HDV handling, if you want to be sure. Of course, the fact that your favorite edit package doesn't speak HDV today is no guarantee that it won't tomorrow. Check the Web site for your product and you might discover that there's an upgrade or a new version that is HDV-capable coming soon. This also means that all the critical components in your edit suite need to be able to handle the HDV data stream comfortably. So old, slow hard drives and sluggish input/output or video display cards also might not be up to the task.

Aftershocks

Another aspect of the new HDV shuffle that's often overlooked is the general production suite gear you'll need to play the HDV editing game. Remember that while your camcorder and even your NLE might be HDV capable, that doesn't mean the cables you have lying around or the video monitors you use in your edit suite will be up to the task.

One of the coolest aspects of the HDV design is the fact that they managed to compress the data stream enough to send it down standard IEEE-1394 (FireWire, iLINK) data cables. So you don't have to re-wire your entire studio for SDI or other expensive HD data transfer systems. But your old composite and/or S-video cables that play nice with SD DV tasks like hooking your computer output to your current SD monitor won't cut it if you're going to migrate to HDV– not if you want to view your HDV output on a real high-definition monitor, anyway.

And speaking of video monitoring, that's a pretty big issue in the coming HDV world. If you're editing in HDV, it's assumed that you'll want to see the actual HD video you're producing — in HD. And this is one area where you need to be very careful.

In my experience, the most affordable way to do high-def monitoring is with LCD displays like those on modern computers. However, I've never yet met an LCD monitor that was truly accurate when it comes to reproducing TV colors.

Every professional video producer I know still uses cathode-ray-tube (CRT) displays to check for color accuracy in their edit suites. It's the same technology in your home TV, but unlike a home TV, a pro monitor is designed for accuracy, rather than optimized TV playback. A CRT-based pro video monitor is still the only truly dependable way to judge what your video signal actually looks like. If you are going to take the HDV plunge, you'll probably want to sharpen your pencil and calculate some of these peripheral costs beyond the camcorder and software upgrade.

Building Your HDV Future
So when it comes to HDV, the bottom line is that this presents a whole new world of capability for the videographer to get his or her foot in the door of high-def production. It's truly revolutionary technology that could well speed the transition from today's SD world into the HD world we all know is coming. But, as with all major technological shifts, there is going to be some pain along the way. If you want to play, it'll take some additional research on how the particular software packages you use today will adapt to these new bigger HDV data streams. And you'll need to make an assessment of how much it will take to get both your shooting and editing gear up to spec.

But if you decide to take the plunge, you'll also discover that you're part of a brave new world — affordable true high-definition video production. The future is sure starting to look a lot like today.

Bill Davis writes, shoots, edits, and does voiceover work for a variety of corporate and industrial clients.

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