getSmoothContour: Smooth contour from anchors

In tatters/soundgen_beta: Parametric Voice Synthesis

Description

Returns a smooth contour based on an arbitrary number of anchors. Used by soundgen for generating intonation contour, mouth opening, etc. Note that pitch contours are treated as a special case: values are log-transformed prior to smoothing, so that with 2 anchors we get a linear transition on a log scale (as if we were operating with musical notes rather than frequencies in Hz). Pitch plots have two Y axes: one showing Hz and the other showing musical notation.

Usage

getSmoothContour(anchors = data.frame(time = c(0, 1), value = c(0, 1)),
  len = NULL, thisIsPitch = FALSE, method = c("spline", "loess")[2],
  valueFloor = NULL, valueCeiling = NULL, plot = FALSE, main = "",
  xlim = NULL, ylim = NULL, samplingRate = 16000, voiced = NULL,
  contourLabel = NULL, ...)

Arguments

anchors	a dataframe of anchors with specified time and amplitude. achors$time can be in ms (with len=NULL) or in arbitrary units, eg 0 to 1 (with duration determined by len, which must then be provided in ms). So anchors$time is assumed to be in ms if len=NULL and relative if len is specified. anchors$value can be on any scale.
len	the required length of the output contour. If NULL, it will be calculated based on the maximum time value (in ms) and samplingRate
thisIsPitch	(boolean) is this a pitch contour? If true, log-transforms before smoothing and plots in both Hz and musical notation
method	smoothing method: 'spline' or 'loess' (default). Consider 'spline' if you have a lot of anchors and not much patience, since it is much faster than 'loess', but it may produce weird results when there are only a few anchors
valueFloor, valueCeiling	lower/upper bounds for the contour
plot	(boolean) produce a plot?
main, xlim, ylim	plotting options
samplingRate	sampling rate used to convert time values to points (Hz)
voiced, contourLabel	graphical pars for plotting breathing contours (see examples below)
...	other plotting options passed to plot()

Value

Returns a numeric vector.

Examples

a = getSmoothContour(anchors = data.frame(
  time = c(50, 137, 300), value = c(0.03, 0.78, 0.5)),
  voiced = 200, valueFloor = 0, plot = TRUE, main = '',
  samplingRate = 16000) # breathing

a = getSmoothContour(anchors = data.frame(
  time = c(0, .1), value = c(350, 800)),
  len = 5500, thisIsPitch = TRUE, plot = TRUE,
  samplingRate = 3500) # pitch

# a single anchor gives constant pitch
a = getSmoothContour(anchors = data.frame(time = 0, value = 800),
  len = 500, thisIsPitch = TRUE, plot = TRUE, samplingRate = 500)

# two anchors give loglinear pitch change
a = getSmoothContour(anchors = data.frame(
  time = c(0, 1), value = c(220, 440)),
  len = 500, thisIsPitch = TRUE, plot = TRUE, samplingRate = 500)

tatters/soundgen_beta documentation built on May 14, 2019, 9 a.m.