The MPEG-Plus-Mac Mess

I used to think there were at least two things you could count on in this impermanence-filled world:

1) that a 10-plus year old, industry standard multimedia codec, MPEG-2, would by now deliver broad interoperability and stability, and

2) that the Apple hardware-plus-operating system-plus-applications combination would be an overall superior alternative to the Windows-based approach for multimedia tasks

I was wrong, on both counts, at least judging from recent events. My first hint of brewing trouble came when, in reading the documentation for my Elgato EyeTV 500 HDTV external (Firewire-tethered) tuner and corresponding PVR software, I saw that 'it takes a dual-processor G5 to display full size, full frame rate HDTV'. I confirmed this statement by using Apple's CHUD (love that name…. Computer Hardware Understanding Development) Tools to disable my PowerMac's second 1.8 GHz G5 CPU, whereupon I experienced frame drops with 720p material from Fox (1081i material would have been even worse). Coming from a Windows background, this shortcoming was baffling to me; graphics chips have had MPEG-2 decode subsystems (iDCT, motion compensation, color space conversion, etc) for many years now, Windows applications have supported them in a proprietary fashion for almost as long as they've existed, and Microsoft's DirectX VA API now unlocks their capabilities for use by any Windows application.

I read further through the FAQ and found my answer; the graphics chips' MPEG-2 decode subsystems 'are used exclusively by the Apple DVD Player, they are currently not available to third parties and…..note that QuickTime does not use these features either'. So the only Mac OS X program that can tap into MPEG-2 hardware acceleration, at least until the advent of the Core Image and Core Video APIs that'll appear in the upcoming 'Tiger' OS 10.4, is Apple's DVD Player (and, according to AnandTech, it's not a particularly good implementation). That's really lame. Unless I'm playing a DVD, the MPEG-2 decode subsystems in my PowerBook's Nvidia GeForce FX Go5200 GPU, and in my PowerMac's ATI Radeon 9600, are sitting there unused.

Continue with my next blog post, More Mess….