Three years ago, a modified Xbox with a larger hard drive and XBMC installed was by far the best way to go about building yourself a cheap, easy to use HTPC.

There were limitations — digital sound and component video were a no-no without the High Definition AV Pack — which wasn’t available in Australia. Assuming you imported one, you’d have to switch to NTSC (requiring a supporting TV and mod chip for those in PAL countries), and then you could enabled 480p, 720p and 1080i video. Needless to say, a lot of people took this path.

Ah Xbox. You sure were big and boxy.

The Xbox, however, is only a poor little custom Celeron 733MHz with a modified GeForce 3, and simply doesn’t have the muscle for high definition video. So when the Xenium modchip inside my Xbox died (and I discovered buying a new chip cost more than the console), it was time to build something with a little more grunt.

Consolation prize

Consoles are out of the question. While the PlayStation 3 is the very definition of lovely, it doesn’t support the .mkv container format or myriad codecs often found within. The Xbox 360 has similar video support, but doesn’t like older DivXs as much and doesn’t support Blu-ray. Both rely on Digital Living Network Alliance (DLNA)  enabled devices for network streaming, with no fallback to plain old SMB. While there’s certainly transcoding options like TVersity, the answer for flexibility, longevity and original quality video seems to be in the PC.

Hardware Requirements

The HTPC should be small and unobtrusive — after all, its job is to stream and decode video, not be a storage box. If possible, it shouldn’t require line of sight contact for the remote. It should be able to decode both VC-1 and H.264 in GPU.

Up until now, boards based on AMD’s 780G have been the best solution for reasonably small, feature rich HTPCs. The other option, often taken by clueless PC manufacturers, was a monster case with desktop parts in it.  While the monster cases became vaguely attractive in 2008, a few things at the end of the year really got the ball rolling in getting HTPCs smaller and less obtrusive.

One of the important bits was Intel’s Atom — the miniature CPU that featured in almost every netbook under the sun. While completely incapable of high definition video on its own, paired with the right GPU it should be more than enough power for the task. Thank goodness then for Nvidia’s Ion platform.

Nvidia's Ion should make tiny, high definition HTPCs possible

Traditionally, you’d opt for an ATI card in an HTPC, as ATI cards supported full offload for VC-1 decoding, whereas Nvidia cards did not. This changed in October 2008 however, and the 9400 platform the Ion is based on supports this. Incidentally, so do all the new MacBooks, perhaps hinting at a Blu-ray update soon…

We can only hope Nvidia has overcome its ridiculous overscanning issues on HDMI, which have been occurring on and off for around three years now.

Speaking of HDMI, the specs claim “true-fidelity 7.1 audio”, whatever that means, presumably offered over HDMI and optical. There’s no mention of Dolby TrueHD or DTS-HD, so we’ll have to file this one under wait and see.

Presumably it’ll be sold on to partners, which is good, as the reference enclosure is amazingly ugly thanks to the port parade on the front, not to mention the seeming lack of room for internal storage.

Oh my... that is an ugly reference enclosure.

Thankfully we don’t need much storage, since it’ll be mostly streaming from our file server. In the cases where video won’t stream however, we’ll need to create a local copy. Given that a dual layer Blu-ray disc tips 50GB and we want this thing to be small (and preferably silent), a 64GB SSD looks like the best bet and will set things back around AUD$300. If the wallet is hurting, then a 120GB 2.5″ Samsung mechanical hard drive probably isn’t too bad a compromise at AUD$90.

The Ion supports gigabit ethernet, although technically it doesn’t need it — Blu-ray quality video and audio requires a peak bitrate of 54Mbps, which works out to be 6.75MB/s (for those a little lost here, lower case b represents a bit, while upper case B is a byte. There are eight bits in a byte). Under ideal conditions, 100Mbit is totally capable of this — still, gigabit is prudent should other things need doing over the network simultaneously. While nice, wireless really still can’t be trusted for continuous, strong throughput in a large number of situations.

There will be some screaming about the lack of TV tuner  — Australian TV is still far enough behind the US that downloaded episodes are a much better option, not to mention local content for the most part, isn’t that good. There are exceptions, but if this is the case, you may as well buy the DVD, rip it to the media server for safety so the disc doesn’t get damaged, and stream anyway.

Finally, we’ll need to put a Blu-ray reader somewhere in the circuit — although despite showing up at CeBIT in March 2007, slim slot loading drives appear to be only in the US and UK at this point in time, and fetch a healthy price of USD$300 on eBay.

Of course, all of this could be completely moot should Apple actually update its Mac Mini line next week — if the thing is silent I’d happily lay down some cash for both an attractive case with powerful insides.

The Software

Love it or loathe it, Windows Media Centre on Vista is reasonably good these days. Still, it’s not a patch on the original XBMC for usability.

XBMC has its own problems though since it left the land of Xbox. It’s in the throws of porting to Linux, although Windows and Mac ports exist as well. It looks like no GPU acceleration is currently present for video, unless the inbuilt libavcodec will offload to DXVA under Windows (or Media Player Classic Home Cinema can be shoehorned in, and even that may have compatibility issues with DXVA supported VC-1 on the Ion platform). The picture in Linux looks bleaker. Otherwise, we’re talking an unhappy CPU.

Evidence online also points to it lacking Dolby TrueHD and DTS-HD support (this will likely make the next release, although bitstream support will require quite new hardware), but most importantly, it also won’t touch Blu-ray. This is more than just overcoming DRM,  XBMC may not even understand the structure of a Blu-ray disc, requiring an external application to be loaded, as far as I can tell a feature not yet supported.

In short, there’s some work to be done yet.

There is one other option in the mean time. I’ve heard MediaPortal has made great strides since I last investigated it in 2004, where it was flaky, but promising. This, along with the file server, will be a mighty experiment.