[Mp4-tech] Re: Difficulties understanding MPEG-4 audio profilesandlevels

[Marc Jaeckle]

> We had the same problem while specifying the various conformance test 
> sequuences to the individual levels. Hence, whe have drafted some 
> formulas. Check out ISO/IEC 14496-3:2001/Cor 1:2002. You will find 
> there formulas to calculate RCU and PCU for a wide range of AAC 
> configurations.

I had a look at the document but I couldn't figure out all the 
abbreviations used in the formulas. Searching the standard for PCU_ref, 
RCU_ref, fs_ref, #DepCouplingCh and #IndepCouplingCh didn't produce any 
results. Can you possibly provide the terms they stand for or in the 
case of PCU_ref, RCU_ref and fs_ref the place where I can find the 
correspoding values (I'm guessing that those are the values from table 
1.3 "Complexity of Audio Object Types and SR conversion" but I'm not 
really sure)?
Actually I would be even more grateful for a short explanation of the 
formulas/terms since I'm pretty(completely) new to MPEG-4 audio and 
probably wouldn't be able to interpret the meaning of the terms without 
reading most of the standard (which I should of course :-) unluckily 
this is not an option at the moment).
Gruß
Marc