Yeah, so today was practically Christmas for the Mac geek. So many new toys, new life for old toys, and the chance to play with it all.

The big one? It looks like the chip in the iPod is finally living up to spec that everyone knew about last year. h.264 decoding at up to 640×480 and all it took was a firmware upgrade to enable it. So what in the world were they holding out for? Movies in the store seemed hardly a reason to disable that for the past year. Whatever the reason, I had some exploring to do.

Lately I had been playing around with my HD captures as to what really looked better on the iPod using tv out. It turned out that for twice the bitrate, full size mp4 actually did look better than 1/4 size h.264 at half the bitrate on a tv. If you're just going to watch on the iPod display though, why waste the space, and that's why I had been doing the standard h.264 iPod export function all along. But bringing these HD caps of Ireland from PBS down to the parents house to show them got me wondering if the full size mp4 wasn't the better option. Well, it was far better for tv viewing as a couple tests showed, even though I detest that visual quality on a monitor. So, in the end, it just takes knowing what you want the file to be viewed on.

Enter the new firmware update. Now we're told we can do h.264 at that resolution as well! HOT DAMN!! That should mean more clarity at the same bitrate, or the same quality in a smaller file. I got right on it. I took a piece of hd-ish video that I had sitting there and exported it through the new “Export to iPod” setting, which magically enough, exported a 640 wide h.264 for the iPod. Plugged in the iPod, and blammo… it played. Oh joy of joys! Apple wasn't screwing us over by releasing new hardware that was identical to last years and claiming that only the new hardware can this.

So I set about to do a test and see what the visual quality differences really were. I had just captured tonight's episode of House and that was a good place to start. 720p, down converted to 480p ought to be nice and crisp. I start with the standard mp4 export. Wait a bit… done. Now for h.264. I know the tech specs say 640×480 (which means a max of 307200 pixels), the h.264 has to be baseline and a max bitrate of 1500kbs and the audio has to be Low Complexity at a max of 160kbs. So I set it up as 640×360, 1500kbs h.264 and 128kbs LC-AAC. Wait a bit…. done.

I took a look at them in QuickTime Player and was getting excited noticing how much better the h.264 was over the standard mp4. Then I'm thinking… you know… 640×360 is way under the limit. I bet I can take it higher for pixel density since it was proven in the past that the resolution numbers are not the limiter, but that final pixel count. Did the math and figured that 720×404 would work as well. So I ripped one of those and got all giddy at how much better that was as well.

So I take it all into iTunes, tag it and prep it for a test on the iPod. Hmm… the iPod isn't taking any of it except the standard mp4. So, I export the recording losslessly to something that QuickTime Player can open and export it there. Hey, it works. But….

Well, take a look. Large PNG's ahead so there is no jpg artifacting.

This is the standard mp4 output.
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This is the QuickTime Player “Export to iPod” function.
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This is the h.264 profile I made to fit spec.
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Now, is it just me, or does the QT export look almost identical to the mp4 output? Whiskey Tango Foxtrot. And I can find nothing different about the two h.264's. So I take a look at the specs again and notice that it's not just Baseline h.264, but it's called Baseline Low-Complexity. Now, I don't remember it being called that before, but I'm thinking now this is yet another step down the AVC ladder to make more compatibility with slower processors. Which might explain why the QuickTime Player output is practically the same as the mp4. It's barely a step above the MP4 Simple Profile spec. And if that's the case…. pshhh….. I really don't care about it then. I guess I'll just have to wait and see how this plays out over the next couple days as the real developers get to work on making their apps produce proper files.

At least the gapless playback finally came along.

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