Frq-band signal energy method

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Frq-band signal energy method

Compute the signal energy in the specified frequency bands. One energy (rms) function is computed for each band using the FFT power spectrum. The result is a set of parameter functions RMSB(t,i) (with: i = band index, from 0 to n-1) which can be saved in the DataSet.

V2 method frq band signal energy.png

The controls below the text amplitude selects the energy value display range. All values are specified in dB.

min/max, floor/range, auto/range, auto

The amplitude range can be specified using minimum and maximum values, a floor and a range, a floor with an automatically calculated range based on the signal's content, or completely automatically.

weighting - none|A|C|Hth|FM(phon)

The Hth is a weighting based on the hearing threshold. The FM(phon) weighting is the Fletcher-Munson equal-loudness. Note that the Hth and FM(phon) weightings only make sense if the signal is calibrated.

band definition

Selects how the frequency bands are defined. It is possible to specify the minimum and maximum of each frequency band (as specified), or two methods can be used to split a frequency range automatically into bands (linear (equal bw) and geometric (constant q), see below).

number of bands

Number of frequency bands. For the definition type as specified, this number must be between 1 to 10, otherwise it must be greater than or equal to 1.

relative energy

If checked, the relative energy (density) is computed by scaling each band energy with: bandwidth / samplingrate * 2.

multiple colors

If checked, each band is drawn using a different color. The first band is drawn using the color specified in the method list 'line' column. The colors specified in the color scheme's function lines tab are used.

band 1-5 and 6-10 (in Hz)

In this fields the user lower/upper limit of the user defined frequency bands can be entered. Overlapping bands are possible.

For the band definition linear (equal bw), the frequency range is splitted into bands with equal bandwidth. For the band definition geometric (constant q), it is split into bands with constant ratio: centerfrequency/bandwidth.

use full bandwidth

If checked, the whole available signal bandwidth is analysed (0 .. sampling rate/2), otherwise the user defined frequency range is used.

first band, last band

The user defined frequency range. Lower frequency of first band and upper frequency of last band (both in Hz).