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Edit Review: AJA Video Systems Io HD

The AJA Video Systems Io HD marries the uncompressed HD I/O and
up-/cross-/downconversions of the AJA Kona 3 card (no Dual Link HD-SDI or 2K, however) to Apple”s ProRes 422 codec.

Mention video I/O for the Mac, and chances are “Kona card” will enter the conversation — even among production people who know little about Mac-based editing. Such is the popularity and reliability of AJA Video Systems’ inexpensive QuickTime-based, uncompressed 10-bit video-capture cards.

The three Kona card lines — LS, LH, and 3 — offer, respectively, I/O for SDI/analog, HD-SDI, and Dual Link HD-SDI for 2K. Street prices (from B&H Photo Video) range from $900 for the LS series to $2,500 for the Kona 3. $300 more gets you AJA’s breakout box, 1RU high, for each card.

Taking a closer look, the high-end Kona 3 also enables hardware acceleration for DVCPRO HD and HDV, and it provides up-/cross-/downconversion between SD and HD with full SD/HD component analog output.

For those unwilling or unable to use PCI cards — laptop owners, for instance — AJA and Apple codeveloped a small family of standalone devices that connect to Macs externally via FireWire and merge the capabilities of Kona cards with the connectivity of a breakout box. AJA offers two versions of the devices, called the Io family, for less than $1,000 — the Io LD (10-bit SDI I/O) and Io LA (10-bit A/D, D/A) — as well as a full-fledged SD rackmount version called merely “Io” (about $2,000).

These are now joined by the Io HD, which marries the uncompressed HD I/O and up-/cross-/downconversions of a brawny Kona 3 card (no Dual Link HD-SDI or 2K, however) to the latest codec on the block, Apple’s ProRes 422, embedded in the Io HD hardware.

ProRes 422 is, of course, the new reduced-bit-rate mastering codec Apple introduced alongside Final Cut Studio 2 at NAB 2007. It has full 1920×1080 or 1280×720 I-frame DCT, 4:2:2, 10-bit sampling, and variable-bit-rate compression, with transport bit rates of 220Mbps and 145Mbps. Apple boasted at NAB that, despite data rates less than those of uncompressed standard definition (SDI is 270Mbps), ProRes 422 is “indistinguishable” from uncompressed HD — and it plays from a MacBook Pro.

Apple blazed no new trails here. Once upon a time, Sony breathed more years of life into Digital Betacam tape transports (themselves adapted from consumer Betamax) by limiting the bandwidth of HDCAM’s camera signal, then compressing it to fit a standard-definition footprint (the first use of 1440×1080). Avid similarly introduced its DN×HD compression in 2004 to enable the use of reduced-size HD signals in an otherwise SD environment. The DN×HD original bit rates were 220Mbps (10-bit and 8-bit) and 145Mbps (8-bit). At that time, there were various demonstrations showing how HD-video signals reproduced through 10 generations of DN×HD at 220Mbps suffered no noticeable quality hit. People were understandably impressed.

The Io HD offers HD-SDI, HDMI, component, composite, and S-Video connectors for video; four XLR channels, eight channels of AES digital, and a pair of RCAs for monitoring audio; and a 9-pin connection for RS-422 deck control.

But there’s a distinction between DN×HD and the newer ProRes 422 that could prove significant to some. While both are DCT-based (i.e. they use checkerboard-like macroblocks to segment the video frame for compression), the older DN×HD is constant-bit-rate (CBR), while ProRes 422 is variable-bit-rate (VBR), sometimes called “smart” encoding. What’s the difference? Digital tape decks and video transmission use CBR, which keeps the data rate constant whether or not the images vary in their amount of detail. In other words, constant bit rate/varying quality of compression. DVDs, by contrast, adopt variable bit rate/constant quality: MPEG-2’s compression actively adjusts to the demands of the material. Ever wonder how a DVD averaging 4Mbps can look so good?

The Io HD leverages the faster bus speeds of FireWire 800, which is how it connects to a Mac. Along with greater file-transfer bandwidth, the Io HD also hikes required Mac hardware specs: At minimum, you’ll need a Power Mac G5 Quad 2.5GHz, a four-core or eight-core Mac Pro 2.66GHz, or a MacBook Pro with an ExpressCard/34 card for a FireWire 800 bus or SATA controller. (G4 owners such as me are flat out of luck.) The reason for the ExpressCard/34 add-ons for the MacBook Pro is that the Io HD demands its own FireWire bus, and it won’t share it with other peripherals such as drives, decks, or cameras — which are forced to occupy a separate FireWire bus when the Io HD is in use. In the case of a G5 Quad or Mac Pro, the easiest workaround is to add an inexpensive PCI-X and PCIe FireWire card.

The built-in handle belies the fact that there is no battery-power option for the Io HD. Be sure you have access to a 120V-240V, 50Hz/60Hz outlet wherever you”re going.

By eye, the Io HD looks roughly 2RU to 3RU in height (a rack unit is 1.75in.), but you can’t really judge it that way because it’s designed for portability, not rackmountability. It’s rolled aluminum, the size and shape of a gray shoebox, with a prominent carrying handle recessed into the narrower side. Below the handle is perforated grille with a hidden fan whirring somewhere inside. Gee, where have we seen these design gestures before? (The fan in the review unit was subtly but audibly whiny. I think manufacturers of air-cooled electronics should post decibel levels, as film-camera manufacturers do. Maybe noiseless fans could be offered as a premium upgrade? I’d go for it. Anything to squelch these things.)

While the handle says, “Pick me up and carry me to location,” the lack of a battery-power option says, “Whoa, you better find a 120V-to-240V, 50Hz/60Hz outlet first.” Maybe a future version could have a Sony V-Mount or Anton Bauer Gold Mount tucked into, say, the bottom of the unit? As it is, the power supply is built-in, so all you need is a simple common power cable. (No external power supply to misplace.)

My review unit lived mostly atop a Mac Pro dual-processor 3GHz Dual-Core Intel Xeon workstation running the latest version of Tiger, OS X 10.5.2. The girth of the Io HD matched that of the Mac Pro and fit comfortably between the Mac Pro’s handles — although often I propped the front end of the Io HD on the Mac’s front handle so I could watch the dancing 8-channel LED audio display (in case I ever happened to have eight channels of audio).

To get started, I installed AJA’s installation software — which checks the Mac for minimum requirements and then installs the latest drivers. (Mine were Version 5.1.1. AJA seems to update Io HD drivers regularly, which are easily downloadable from its website.) Upon installation, settings for the Io HD appear in the Audio/Video Settings preset tabs for Sequence, Capture, Device Control, and AV Devices in Apple Final Cut Pro 6. FCP 6 software is mandatory because it contains the ProRes codec.

Also installed is a breezy little program called AJA Conflict Checker, which does just that, and a standalone program called Io HD Control Panel, which acts as a graphic patch-bay for routing inputs and outputs or selecting codecs, timecodes, format conversions, etc. Easy to grasp; I really liked this approach.

I tried capturing the playback of uncompressed HD from a Sony PMW-EX1 XDCAM EX (1080p30) via HD-SDI to ProRes 422 HQ (10-bit, 220Mbps), as well as HDMI from a Sony HVR-Z7U (1080p30) to ProRes 422 HQ. It was smooth sailing, and I enjoyed the freedom and ease of intercutting the two to make some interesting impromptu comparisons.

The unit comes installed with Io HD Control Panel, a sort of software patchbay. Here, the application shows a 1080i HDMI signal on the input side, and indicates that a 1080i output signal is available via HD-SDI output, the HDMI output, or as a component-analog HD output.

I mentioned at the outset that the Io HD merges the capabilities of a Kona card with the connectivity of a breakout box. To be more specific, the Io HD does not offer Dual Link HD-SDI or uncompressed capture of 4:4:4, 4:4:4:4, and 2K as a Kona 3 card does. Its purpose in life, instead, is to facilitate capture of SD or HD by means of ProRes 422 compression. To do this, it extends all the frame rates, segmented frame schemes, and codecs (transcoding to and from) that FCP 6 is already capable of, along with up/cross/down format conversions (no frame-rate conversion).

As a video I/O breakout box, the Io HD possesses HD-SDI (two of them), HDMI, component, composite, and S-Video connectors. For audio I/O, there are four XLR channels, eight channels of AES digital, and a pair of RCAs for monitoring. Plus a 9-pin connection for RS-422 deck control.

That’s an incredible amount of connectivity tied to one FireWire 800 cable, which is what makes the Io HD hands down a breakthrough product — particularly for MacBook Pro editors working in HD, who are now armed for bear while on location. Ironically, I did not get a chance to test drive the Io HD where it counts most: on the road. Maybe you can.

Two caveats: the minor one, for me, is that when working with Apple Color, the Io HD outputs only SD — even if the original is HD (it downconverts). More of an issue is the lack of HDV support. There is not a FireWire 400 connector to be found on Io HD. Given the time I spend in the HDV world — and the near-universal desire to immediately transcode to a more flexible, less scrunchy codec such as ProRes 422 — I can’t understand this omission. Yes, I know you can set FCP 6’s Capture Preset to ProRes 422 when capturing HDV, but as long as you’ve got a nimble ProRes 422 hardware codec humming in that pricey box tethered to your laptop, why not use it? A hardware assist to HDV output wouldn’t be bad, either.


Company: AJA Video Systems

Product: Io HD

Assets: Plenty of connectivity options, uses Apple ProRes 422 codec, offers FireWire 800 for faster speed, accessible interface.

Caveats: No FireWire 400 connector for HDV editing, automatically downconverts when editing in Apple Color, not compatible with Power Mac G4 or lower, no battery-power option, fan is whiny.

Demographic: Mac editors who need a robust I/O option in the suite or on the road.

PRICE: $3,000 (STREET)

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