User's Manual - Cornell Lab of Ornithology - Cornell University

Chapter 7: Correlationaffect the value of the correlation (Figure 7.7d, e). If your application requiresthat the similarity measure incorporate information about the absoluteamplitude levels of the signals being compared, you should turn Normalizeoff; otherwise it should probably be left on.(a)(b)(c)Normalizeda * aa * b(d)Non-normalizeda * a(e)Non-normalizeda * bFigure 7.7. Comparison of normalized and non-normalized correlations. Thecomplex envelope of the waveform correlations is shown. (a) Waveform of asyllable from a mockingbird song. (b) Same waveform amplified by a factor of2. (c) Normalized correlation; the correlation between (a) and (b) is identical tothe correlation between (a) and itself. (d) Non-normalized correlation between(a) and itself. (e) Non-normalized correlation between (a) and (b).Complex envelopeThe complex envelope option applies only to waveform correlations, and isdiscussed in the section “Waveform correlations” later in this chapter.Canary 1.2 User’s Manual 115