Lemur Synthesis Parameters
Synthesis of a new audio signal from the data in a Lemur analysis is a simple matter of tracing the behavior of a
single sine wave for each track in the analysis file. A track consists of a series of spectral peaks, each with a
known amplitude, phase, and estimated frequency, and each with a link to the next peak in the track. For each
track, therefore, the amplitude, phase, and frequency estimate are known at several points in time, and are
assumed to modulate smoothly between these known values. Track amplitudes are modulated linearly between
frame boundaries. Track frequencies are modulated parabolically to preserve phase accuracy at frame
boundaries (McAulay and Quatieri,
1986).
Lemur can synthesize AIFF files from analysis data at any sample rate, using 16 bit or 8 bit samples.
Lemur can optionally normalize the amplitude of the synthesis, such that the largest sample magnitude is
1.0. This requires two passes through the synthesis phase, and therefore takes twice as much time as
ordinary synthesis.
The Sample Rate, Sample Size, and Normalization for Lemur synthesis may be set in the
Synthesis Parameters panel, accessed from Lemur's Parameters menu.
Forward to Modified Lemur Synthesis
Back to Lemur Track Formation
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