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Non-Linear Digital Video Editing on Windows NT

You might be a number-cruncher all day, but deep inside you can hear a little voice that says you really could be making movies. Forget the ergonomically correct chair that you sit in all day: You want one of those cool director's chairs with your name stitched on it. Well, that computer on your desk could be your ticket into the world of movie-making. Editing words, images, and audio on a computer are all common tasks.You could edit video, output it straight to tape, and distribute it to all your clients and friends.

It sounds easy, but you probably haven't made your first movie because television-quality video is a tremendous data-hog. Each frame of digital video has a resolution of 720 x 480 pixels, and you need 30 frames-per-second (FPS). If you want to record video straight to your hard drive, you'd need an audio/video (A/V) drive that's capable of sustaining a data rate of more than 20MB-per-second (MBps). Right now, those don't exist. Some of you might think of throwing together a five- or six-disk RAID system, but that would cost you a ton of cash.

One thing you can do is compress your data. Then you can record video onto readily available and relatively inexpensive hard drives. However, there is generally a trade-off between the amount of compression and the quality of the image: You'll need a dedicated capture board if you want real television-quality video.

Perception Video Recorder
Digital Processing System's Perception Video Recorder (PVR) is a high-quality product for recording and playing back video. It runs under Windows or Windows NT, on both Intel Pentiums and Digital Equipment Alpha CPUs. PVR is able to squeeze exceptional-quality video out of your computer because it uses an optimized version of the Joint Photographic Experts Group (JPEG) compression scheme.

PVR is a full-length PCI card. If you want to grab video, you'll need to add the video-capture daughter card. This daughter card extends enough to effectively take up an extra slot. PVR doesn't record or play back audio, although it supports a number of audio boards. The card also has its own SCSI controller to allow connection of PVR's dedicated hard drives: These drives are not system drives, but they are devoted to PVR. There are two connectors on the back, one for input and one for output. Each connector is a little octopus of cables with connections for sync, composite video, S-Video, and component video.

This makes PVR a perfect match for the BetacamSP video format, the current high-end standard for applications such as corporate video and broadcast news. Don't confuse BetacamSP with the old BetaMax standard that VHS wiped off the face of the earth. BetacamSP is a whole different beast, and it's recently become more affordable with decks now in the $7,000-$10,000 range.

PVR's software is straightforward. You play animations using a VCR-type control panel. If you want to create a clip from a series of animation frames, you simply choose Open from the pull-down menu, select the frames, and hit OK. Most of PVR's operation is this easy.

PVR is basically a high-quality digital VCR, but it has a number of goodies thrown into the mix. For example, you can convert PVR clips for use with Adobe's Premiere software package. There's a complete set of diagnostic and file management utilities and useful graphics, including color bars, to fine-tune your video setup. You can also perform a number of effects in real-time, such as playing a clip in black-and-white or playing a clip at film's 24 FPS speed instead of video's 30 FPS.

PVR has a number of quality settings you can choose from. If you're creating digital video for a CD-ROM or multimedia application, you can capture acceptable quality at a 2MBps level. For broadcast-quality animation, you might want to use "Broadcast level" (5Mbps) or "Digital level" (6MBps). You should be aware that even fast A/V hard drives can't always maintain 5-6MBps levels across the entire drive's surface. If you're using 6MBps, you might be able to use only a third of the drive's capacity. If you're working with longer segments of video, DPS suggests you use the 4MBps setting because it can be maintained across the entire drive. PVR software also includes a utility for testing your drive's performance.

Running PVR under Windows NT offers a couple of useful advantages over non-NT operating systems: PVR's SCSI drives are invisible to the system without NT. If you use NT, your animation and video sequences are not only visible, they are accessible to any application in a variety of file formats.

This offers you an advantage when you record animations. On non-NT versions of PVR, the animation program needs to save the frames to a system hard drive. You then import your frames into PVR. If you work on NT, you can save the frames straight to PVR, and you don't need to have a few hundred megabytes of free space on your system drives.

PVR has some basic editing capabilities: You can arrange your clips in any order, choose in-and-out points, and create simple cross-fades and dissolves. It's a rudimentary editing package, but you can use it to put together simple projects, such as a demo reel, quickly and easily. It also adds a tremendous amount of creative freedom, especially for animators: You can cut up and rearrange your longer animation sequences to create a new look or feel for an animation while the client watches.

Speed Razor Mach III
Speed Razor Mach III, from in:synch, is part of a new category of software for NT that allows you to edit and manipulate video and audio sequences. If you're looking for a real video post-production editing environment, you'll want to take a look at it.

All the elements you'll use in your production are stored in the Razor Library. These elements include video and audio clips, graphics, transitions, and effects.

Razor has a batch-import feature and you can collect your elements with it. To do batch capture, you'll need a pro or semi-pro video deck with an RS-422 port, a free serial port on your computer that's fast enough to handle a high-speed modem, and an RS-232 to RS-422 cable. You enter SMPTE in-and-out points for each clip you want. (This is a method of time-stamping video or audio tape for synchronization purposes as defined by the Society for Motion Picture and TV Engineers.) You then hit a button and Razor controls both the video deck and the PVR, grabbing the footage you've selected.

This has some practical uses. Let's say you've spent the week shooting footage for a training video, and you've made a window dub of your BetacamSP footage onto a VHS tape. (A window dub is a copy that shows the time-code in a window that is superimposed on top of the video.) You go home and pop the tape into your VCR. When you see a scene you like, you write down the time-code numbers where you want the scene to begin and end. When you get back to work, you can enter the in-and-out points in Razor and let it grab the footage from your BetacamSP master tape.

At the start of a project, you load up the elements you plan to use, then you work with them in the Composition Window (see screen 1). The Composition Window is essentially a time-line that lets you stack an infinite number of audio and video tracks and shuffle your elements quickly and easily. You drag-and-drop a video clip onto the time-line: If you want to move an element, simply drag it to the new position. This process is much simpler than traditional video editing, where one change might mean you have to change the rest of the show.

Another important part of any editing system is the variety of transition effects it offers. Razor may handle transitions with a plain-looking interface, but it gives you a surprisingly large range of possibilities. For example, Razor gives you complete control over every parameter of the popular wipe effect (where one video source replaces another), including angle and the amount of edge softness. You can save any transitions you create as presets.The more ambitious can create custom Matte Transitions with the luminance values of a .BMP image to determine how video images replace one another.

Razor has a number of special effects, including color-correction, embossing, cropping, and blurring. Once again, Razor gives you an impressive amount of control over parameters. The Orientation effect is particularly versatile: You can use it as either an effect or a transition. Orientation allows you to resize, rotate, and even spin the video in 3D space. You also have the ability to key or superimpose images, including the "weather announcer"-style blue-screen effects.

Razor includes a character generator because you always need to add titles to your video. The character generator, like the wipe generator, has deceptively simple controls. You can specify font, size, color and text justification, and create scrolls, crawls, and drop shadows.

Final Choices
If you're an animator with an Alpha machine that uses software such as LightWave 3D or SoftImage, you'll want PVR for outputting animations. The operation is simple and the image quality is outstanding. Razor adds quite a bit of power to your PVR setup, but does it really replace a traditional editing suite? If your videos consist mainly of long shots, such as speeches or wedding videos, then a non-linear video setup might not be your best buy. You should consider a couple of video decks and some sort of video titling equipment instead.

Most video today, though, consists of shorter shots that designers edit together with a lot of cool-looking effects and great-looking graphics. If you want to produce that sort of snazzy video, you'll be hard-pressed to beat PVR and Razor with their combination of creative flexibility and top-notch output quality. Maybe it's time to buy that director's chair.

Perception Video Recorder
System Requirements: Intel Pentium or Digital Equipment Alpha CPU, Windows NT Workstation 3.5, 64 MB of RAM, dedicated audio/video hard drive
Contact: Digital Processing Systems * 606-371-5533
Price: $2995
Speed Razor Mach III
System Requirements: Intel Pentium or Digital Equipment Alpha CPU, Windows NT Workstation 3.5, 64 MB of RAM, dedicated audio/video hard drive
Contact: in:sync * 301-320-0220
Price: $1499
Testing Platform
Aspen Systems Telluride: 275-MHz Alpha AXP21064A, 64MB of RAM, 1GB SCSI-2 hard drive, Imagine 128 PCI video card, Micropolis 4GB SCSI-2 A/V hard drive
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