Pitch

One of the types of objects in Praat. For tutorial information, see Intro 4. Pitch analysis.

A Pitch object represents periodicity candidates as a function of time. It does not mind whether this periodicity refers to acoustics, perception, or vocal-cord vibration. It is sampled into a number of frames centred around equally spaced times.

Pitch commands

Creation:

Drawing:

Viewing and editing:

Synthesis:

Conversion:

Inside a Pitch object

With Inspect, you will see the following attributes:

xmin
start time, in seconds.
xmax
end time, in seconds.
nx
the number of frames (≥ 1).
dx
time step = frame length = frame duration, in seconds.
x1
the time associated with the first frame, in seconds. This will usually be in the range [xmin, xmax]. The time associated with the last frame (i.e., x1 + (nx – 1) dx)) will also usually be in that range.
ceiling
a frequency above which a candidate is considered voiceless.
framei, i = 1 ... nx
the frames (see below).

Attributes of a pitch frame

Each frame contains the following attributes:

nCandidates
the number of candidates in this frame (at least one: the `unvoiced' candidate).
candidatej, j = 1 ... nCandidates
the information about each candidate (see below).

Attributes of each candidate

Each candidate contains the following attributes:

frequency
the candidate's frequency in Hz (for a voiced candidate), or 0 (for an unvoiced candidate).
strength
the degree of periodicity of this candidate (between 0 and 1).

Interpretation

The current pitch contour is determined by the path through all first candidates. If the first candidate of a certain frame has a frequency of 0, or a frequency above ceiling, this frame is considered voiceless.

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© ppgb, December 30, 2010