EQ: Improve Matlab compatibility of equalizer filter design plus cleanup
This patch adds checks into places where Octave and Matlab handle
the used functions differently. In previous version the difference
in bilinear transform caused IIR designs to fail totally in Matlab.
There remains an issue with IIR EQs design with Matlab. In that case
a warning text is printed since the problem with tf2sos() does not happen
with all designs (example_spk_eq is impacted). It will be investigated
and fixed later. The problem does not happen with Octave.
Equalizer defaults had accidentally by default boost of one dB compared
to desired filter scaling. the offset (norm_offs_db) is now restored to
0.
In parametric equalizers design renamed BW to Q for the correct purpose
(peaking filter Q-value).
Fixed bug in filters normalization where loudness based scaling of IIR
filters was using calculated value for the FIR part.
Also cleaned up lot commented out lines and simplified some functions
parameters usage.
Signed-off-by: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
6 files changed
