[mad-dev] mad_frame subbands and filtering

Bill Zissimopoulos mad-dev@billz.fastmail.fm
Sun, 29 Jun 2003 22:02:58 -0700

I need to process frame subbands before synthesis occurs. Libmad
conveniently makes them available through its filtering feature. However
the information around filtering is rather limited. I have studied the
source code in filter.c and (think that I) have read all the relevant
articles in this list, so I understand the basics, however I do have a
few more questions:

1. What are the units and range of values for each subband? Must these
values be scaled before they can be used?

[I saw in a list article that subband values range from -MAD_F_ONE to
MAD_F_ONE. Have these values been scaled?]

2. What are the frequency ranges that each subband covers?

Many thanks.