Elgato Turbo.264 H.264 encoder [printer-friendly]

Original URL: http://www.reghardware.co.uk/2007/05/24/review_elgato_turbo264/

Elgato Turbo.264 H.264 encoder

Published Thursday 24th May 2007 11:02 GMT

UK-first review Apple TV and iPod. Sony PlayStation Portable. Different devices, but united in common support of the H.264 video compression technology, part of the MPEG 4 standard. And since a lot of us own these, the need for H.264-encoded content is high. The snag: it takes a heck of a lot of processing power to produce.

Elgato Turbo.264 H.264 transcode accelerator
Elgato's Turbo.264... the hardware

Enter Turbo.264, a dedicated H.264 encoder made by Mac TV tuner specialist Elgato. The size of a large Flash drive, Turbo.264 plugs into a free USB 2.0 slot ready to take over H.264 video encoding from the host processor.

While a Mac's CPU is a great general purpose number cruncher, the chip on the Turbo.264 was designed to do nothing but churn out H.264 video. It's a specialist to the Intel Core chip's jack-of-all-trades, and that should make it much faster. That's the theory - does it work in practice?

Installation is simple. Plug in the USB stick and drag the Turbo.264 application off the accompanying CD. The first time the app is launched, it automatically installs the necessary QuickTime plug-in code to link the multimedia software into the Turbo.264 hardware, and after a quick, optional registration process you're ready to encode video.

The connection to QuickTime means that the Turbo.264 is accessible by almost any application that uses Apple's multimedia software to encode video, not just Elgato's own - Turbo.264 shows up in iMovie, for example. Content is decoded then re-encoded by the Turbo.264, so any format QuickTime understands, even via a third-party plug-in like Flip4Mac's WMV add-in, can be converted into H.264 format. If the Turbo.264 isn't connected, you'll be told to slot it in.

The Turbo.264 application adds some formats of its own, such as the ability to drag a DVD's video_ts folder over and convert its video contents, provided they're unencrypted, of course. In practice, that means ripping the disc first, but at least the conversion to H.264 should be faster.

Elgato's software provides four pre-sets for conversion: iPod-oriented settings for 640 x 480 and 320 x 240 video; a PSP setting that essentially matches the 320 x 240 iPod output, but also generates a 160 x 120 thumbnail image; and an Apple TV option that encodes at the native resolution of up to 800 x 600, downsampling larger content to that size but keeping anything smaller at its original size. The level of acceleration depends on the size of the output.

Elgato's Turbo.264 application
Elgato's Turbo.264... the software

Turbo.264's is a classic Mac app in that it's intuitive to use and removes as much complexity from the process as possible. Drag one or more movies files onto it, and each is listed in the order they'll be converted, with a encoding pre-set pop-up alongside each. Click on Start and you're away.

A speedometer-like indicator at the top reminds you that the Turbo.264 hardware is plugged in or not - handy if you use a desktop Mac and you can't see its USB ports. During the encoding process, there's a time remaining and frame rate readout to complement the usual bar.

To try the Turbo.264 out, we took a six-minute standard definition PAL DV file - size: 1.22GB - and encoded into H.264 in each of the four formats the Turbo.264 app provides. We also converted the same file to match the settings used by the Apple TV formatter, this time with the Turbo.264 unplugged and using the freeware app, MPEG Streamclip 1.8.

Next, we ripped a DVD and encoded the contents first using Turbo.264 then using the popular freeware MPEG 4 encoder HandBrake 0.8.5b1.

All the tests were carried out on a 1.83GHz Core Duo-based MacBook Pro with 1.5GB of memory.

The figures speak for themselves: Turbo.264 is way faster than the host Mac. While the unaided MPEG Streamclip took just short of 23 minutes to encode the six-minute clip, Turbo.264 did it in just under seven minutes, less than a third of the time.

H.264 encoding: CPU vs Turbo.264
Elgato Turbo.264 DV-to-H.264 performance
Shorter bars are better

You can see from the image results Turbo.264 produces a slightly darker, higher contrast image than the original, but watching the results playing back - as opposed to squinting at single frames - is no different from viewing the original. Turbo.264's output might not pass pro video muster, but it's unquestionable fine for iPod, PSP, Apple TV or computer playback.

Video image samples

Original DV frame
(http://regmedia.co.uk/2007/05/21/turbo264_sample_1.jpg)
Click for full-size image

Turbo.264 encoding - Apple TV setting
(http://regmedia.co.uk/2007/05/21/turbo264_sample_2.jpg)
Click for full-size image

CPU encoding - Apple TV-like setting
(http://regmedia.co.uk/2007/05/21/turbo264_sample_3.jpg)
Click for full-size image

Images courtesy BBC/Aardman

Pulling a standard-definition MPEG 2 movie of 1h 55m 58s duration straight off a DVD took Turbo.264 28m 23s to rip and convert to its iPod Standard pre-set. Setting HandBrake to match Turbo.264's settings - 320 x 240 resolution, 128Kbps 48kHz AAC audio, 768Kbps encoding rate, 30fps - ripped the same video and saved it as an H.264 file in 59m 33s, a little more than twice as long.

More up-to-date Macs than mine will see a smaller differential, but while processors are improving, it's still going to be some time before the Mac's own CPU can match the Turbo.264's encoding speed. And the Elgato product costs a fraction of the price of a new Mac.

Converstion to H.264 also produces files a fraction of the size of the original, from 1249.3MB (1.22GB) down to 136.9MB in the case of the Apple TV pre-set and even 31.1MB with the iPod Standard setting. That makes the Turbo.264 handy for folk who've digitised their old VHS tapes for burning to DVD and would like to keep less drive-stuffing back-up copies.

Elgato Turbo.264 H.264 transcode accelerator
Elgato's Turbo.264... and friend

The only flaw with Turbo.264? It's a Mac-only product. Elgato's cagey on Windows support - it might happen, it might not. If it doesn't, there's always ADS' Instant Video To-Go, or apps that make use of the host PC's graphics card to process the video data.

Some users may also find the lack of flexibility irritating. To keep its app user-friendly, Elgato hasn't equipped Turbo.264 with custom compression settings, but an Advanced... section would surely have been easy enough to add. Maybe it will do so in the near future. While the Turbo.264 is so clearly aimed at consumers, video pros are likely to find it handy too, and as they provide feedback to Elgato, I'd expect it to start adding more pro-friendly features.

And there are plenty of devices in addition to the PSP, iPod and Apple TV that can play back H.264 files. Their owners should check out the Turbo.264 too.

Verdict

A couple more CPU generations and the Turbo.264 will be redundant, of course. But why wait three or four years for H.264 encoding speeds you can have right now, for a fraction of the price of a new Mac? And the results speak for themselves: Turbo.264 pumps out iPod, PSP and Apple TV-friendly video in a fraction of the time your Mac can. If you use one of these devices for video, Turbo.264 is a must-have.

	Elgato Turbo.264
Summary	Triple your Mac's video processing power for 50 quid. Bargain...
Rating	95%
Price	€99.95/$99.95 (£51)
More info	Elgato's Turbo.264 page (http://www.elgato.com/index.php?file=products_eyetvturbo)