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The Art Of The Compressionist

Across the decades, producers, editors, artists, engineers -- the whole darn creative family -- have all become enraged and indignant as the typical non-broadcast project draws to a close. Days, weeks, even months of sweat and inspiration are about to be displayed to the world at large, and the vehicle, the medium of choice, is simply abysmal.

In the old days, it was a noisy, blurry VHS dub on ten cents worth of recycled tape, viewed on a 15 -- year -- old monitor which reproduced Caucasian flesh tones like cheddar cheese, and overscanned so badly that a full third of the raster was lost.

These days, it's more likely to be a Web stream the size of a postage stamp, with lip-flap measured in sentences instead of milliseconds. Or maybe it's an MPEG-1 version of your precious program, condemned to play off a 4X CD-ROM drive, stuttered and seizing along before crashing the obsolete player software entirely.

So much for progress.

ADD A SPECIALTY

That's why it's in every content creator's best interests to add yet another specialty to his or her list of marketable skills: Compressionist. Learning the ins and outs of squeezing pictures and sound into tiny files and streams is the only way one can guarantee that the creative process doesn't lead to the trash heap. It's akin to the strategy my cronies and I stumbled upon years ago, when we figured out that by understanding what the engineer saw in the waveform monitor and vectorscope, we could take back some measure of control over the end product.

If only it were that easy to "learn" the arcane art of compression. Video, with its pedestals and percentages and phase angles, is quantifiable, precise and repeatable. Compression, on the other hand, is closer to alchemy, best attempted after burnt offerings to the gods of the codec and the bitrate. Compression is imprecise and frustrating-and when you screw it up, it takes a really long time to find out.

In other words, you need all the help you can get. You could hire yourself a compressionist, if there were such an occupation, but a specialist's salary is somehow at odds with a service the client frequently expects you to just "throw in." If you're smart, you'll stock up on compression software and buy plenty of blank CDR's to ruin.

THE QUEST TO COMPRESS

For most of us, a collection of desktop applications can handle the most common requests. Start with QuickTime Pro, one of the best bargains around at $29.99. QT Pro turns your QuickTime player into an import/export utility, compressing to and from several of the most popular formats, including MPEG-4 and the new 3GPP format used in wireless applications. True, you've got to buy a new version whenever QuickTime jumps a full version number, but it's a small price to pay. Quite literally.

Another easily available compression application is Real Networks' Helix Producer, for programming destined for Real Media streams. "Free" is a pretty attractive concept, and Helix Producer Basic is just

that-available for download at no cost. It's a surprisingly full-featured application in its Basic version, capable of live, on-the-fly stream encoding as well as offline file compression. Upgrading to Helix Producer Plus (under $200) adds expert modes that allow advanced users to tweak the Real format's many parameters, and extends the program's functionality. If Real Media is your compression of choice, you can't go wrong with tools from the format's inventors.

Perhaps the most popular compression toolset is Discreet's Cleaner series, available for $549 in both Mac and Windows versions. The Cleaner development team "leapfrogs" versions from one platform to another, which is why Cleaner 6, a Mac-only version, has been functionally superseded by Cleaner XL, a Windows exclusive. Both versions use similar compression technology, refined over the years to suit advances in processing hardware and operating systems.

INDUSTRIAL STRENGTH

There are several significant differences between Cleaner 6 and Cleaner XL, platforms aside. XL is faster, without a doubt, and there are more compression formats to choose from than ever before, including Kinoma, the format used by PalmOS PDA's and some wireless devices. But for the user, the biggest difference is the workflow, including the look and feel of the program.

While it would be inaccurate to describe previous versions' user interfaces as "dumbed-down," they nonetheless presented a fairly straightforward click-here kind of workflow -- a very linear and single-task feel, despite batch encoding capabilities. Cleaner XL, though, is an industrial-strength workhorse from the ground up, and the interface shows it. The concept of batch encoding is redefined by XL's workflow, which stores dozens of parameters in simple text files, and allows "watch folders" to execute jobs as soon as they become available for encoding. Couple this production-oriented superstructure with a peppy processor, and you've got a hotrodded compression mill that can meet ambitious deadlines.

To be fair, not everyone is prepared for the more stark user interface Cleaner XL employs; it's a bit of an acquired taste, devoid of colorful "Start" buttons and such trimmings. Conversely, if there's one type of encoding you do most frequently, saving a customized job format can mean near-instantaneous starts... no click-throughs. In other words, the "civilian"-friendly interface trades off for speed and power.

THE HARD WAY

Even when creative professionals are armed with a broad array of tools and hardware, compression can remain a confusing task, from recommending or specifying a file format to experimenting with an infinite number of parameter permutations. Trial-and-error remains much too large a part of perfecting your own signature compression, finding the perfect balance of file size and bitrate for a smooth, stunning stream. And while books and message boards can help give you an understanding of the effects of your experiments, you've got to encode a file to really evaluate the results.

Alchemy? Not really. But maybe we all need a semester at Compression College.

Walter Schoenknecht can be reached via e-mail at walter@mmgi.tv.