[Mp4-tech] [audio] max_sfb name is misleading?

[D.Domazet]

Hi all,
This question relates to MPEG-4 GA audio (AAC).
I think that the max_sfb bitstream element's name is a bit misleading. 
In ISO 14496-3 max_sfb is described as: "number of scalefactor bands transmited per group...". so wouldn't it be better to name it num_sfb_per_group.
Decoding goes like this (this repeats many times during coding process):
for(g=0; g<num_window_groups; g++)
{
    for(sfb=0; sfb<max_sfb; sfb++)
    {
        ...[g][sfb] =... ;
    }
}
Wouldn't it be more reasonable to have:
for(g=0; g<num_window_groups; g++)
{
    for(sfb=0; sfb<num_sfb_per_group; sfb++)
    {
        ...[g][sfb] =... ;
    }
}
If we look at the standard, very ofter we have max_sfb lower than num_sfb, and as it's name says "max", it should me possible maximum of something (in this case sf bands), and it is not. For example, for short windows at 44.1 kHz, we can have 120 sf bands, and at the same time max_sfb is 15 or lower! I think that max_sfb should be 120, and actual num_sfb 15, not vice versa. 
Whoever is responsible for the naming should (at least) think about this. 
Any comment is appreciated.
Thanks,
Daniel
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