Stupid bloody Apple, why do they DO things like this????

Folks, this is a tough one, and yes, I've read through the Casey-initiated 
thread. Good start 
but sadly optimistic.

The question is, how do we pump out vids that are 640x480 and have the 
"baseline low-
complexity" profile, thus being both iPod and (presumably) Apple TV compatible?

Baseline can be selected when exporting with your own settings, but the 
"low-complexity" 
sub-option cannot. According to Apple's developer spec, low-complexity has been 
defined 
by Apple for the iPod, and it seems to be restricted to the Export for iPod 
option, which 
cannot be configured.

When exporting an iPod video, QuickTime chooses automatically whether to use 
"baseline" 
or "baseline low-complexity" - in a nutshell, anything upwards of 320x240 gets 
low-
complexity. Gory details here:

http://developer.apple.com/technotes/tn2007/tn2188.html

Three possible workarounds. I am not in front of QTPro right now so will try 
later:

1) Use the Export for iPod option with the source vid sized at 640x480 - this 
will goad 
QTPro into using low-complexity - and then find some way of saving the 
resulting video 
_again_ with a chopped-down bitrate, perhaps by doing a "Save as ..." but 
without re-
encoding. 

2) Do it the other way round - export at the bitrate etc. that you want, then 
run it through 
the iPod export. The developer spec suggests QT iPod exporter using a 640x480 
source 
file will pick its own bitrate according to a complex formula ("DR = { (nMC * 8 
) / 3 } - 100" 
I kid you not, check out the developer link above) between 700 and 1500kbps. 
But maybe 
if the source file is already lower, it won't jump up the bitrate too 
shockingly. The MC in 
the equation stands for "macroblock" and if the number of these can be reduced 
in the 
source file (how? Dunno) then, doing the maths, you are headed for a smaller 
result.

3) Resize your source video to 640x480, whack it through Export for iPod and 
hope the 
filesize is not too bloated. As in the formula above, this should produce 
something 
between 700kbps and 1500kbps, although Apple doesn't say whether the audio is 
included in that bitrate (AAARGH!).   

I found to my horror this afternoon that my carefully crafted 640x480 recipe 
with 
meticulously pared down video and sound bitrates that delivered a file of 
5MB/minute that 
looks alright on the telly via laptop S-Video cable doesn't work on the iPod.

I am just about ready to tell Apple where to shove their TV box ... and all of 
the above still 
leaves the question unanswered: will the aforementioned oblong suppository PLAY 
H.264 
BASELINE LOW-COMPLEXITY???

Anyone got one of these boxes?

That's all for now. I know none of the above is tested but I thought I'd post 
now while my 
blood is up, and to give others the chance to look for a solution.

Waz from Crash Test Kitchen
http://www.crashtestkitchen.com


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