F0AC
F0AC - F0 detection using autocorrelation
The autocorrelation function is first applied to all N windowed frames. The maximum number of candidates (MaxNCandidates) are stored for each frame. The result is a MaxNCandidates x N matrix. The cheapest path through this matrix is found using the Viterbi algorithm. The output is a shell table item which contains the f0-values and the center window positions.
The algorithm used is described in detail in: BOERSMA, Paul (1993): Accurate Short-Term Analysis of the Fundamental Frequency and the Harmonics-To-Noise Ratio of a Sampled Sound. Proceedings of the IFA. Vol 17. pp 97-110
Usage:
FOAC WaveItem DeltaT MinimumPitch PeriodsPerWindow MaxNCandidates SilenceThreshold VoicingThreshold OctaveCost OctaveJumpCost VoicedUnvoicedCost MaximumPitch F0Table
Inputs:
- WaveItem
- The id of the wave item to analyse.
- DeltaT
- The window shift in seconds (expert parameter!; If 0, then DeltaT is computed automatically by
F0AC)
- MinimumPitch
- The lower pitch boundary in Hz.
- PeriodsPerWindow
- The number of periods to fit in an analysis window.
- MaxNCandidates
- The maximum number of autocorrelation candidates for every frame. For every frame a number of f0-candidates (including voiceless candidates) are computed. The atom searches finally one trace through these candidates.
- SilenceThreshold
- The value for the computation of the strengths of the f0-candidates.
- VoicingThreshold
- The value for the computation of the strengths of the f0-candidates.
- OctaveCost
- The value for the computation of the strengths of the f0-candidates.
- OctaveJumpCost
- The value for the computation of the strengths of the f0-candidates.
- VoicedUnvoicedCost
- The value for the computation of the strengths of the f0-candidates.
- MaximumPitch
- The upper pitch boundary in Hz.
- F0Table
- The shell table item for the result (has to be a 2-column table), column
0contains f0-values, column1the center window positions.
Outputs:
- NFrames
- The number of frames.
- NSampWindow
- The number of samples for the analysis window.
- DeltaTOut
- The DeltaT which was actually used (useful if DeltaT was automatically calculated).
- x1
- The position of the first frame.
