| Bark Frequency
Transform Using an Arbitrary Order Allpass Filter Prasanta Kumar Ghosh and Shrikanth Narayanan IEEE Signal Processing Letters, Volume 17, No. 6, June 2010, pp 543-546 |
Abstract:
We propose an arbitrary order stable allpass filter structure for
frequency transformation from Hertz to Bark scale. According to the
proposed filter structure, the first order allpass filter is causal,
but the second and higher order allpass filters are non-causal. We find
that the accuracy of the transformation significantly improves when a
second or higher order allpass filter is designed compared to a first
order allpass filter. We also find that the RMS error of the
transformation monotonically decreases by increasing the order of the
allpass filter.
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(pdf) (Software [matlab code]) |
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