maad.util.plot2d

maad.util.plot2d(im, ax=None, colorbar=True, **kwargs)

Display the spectrogram of an audio signal.

The spectrogram should be previously computed using the function maad.sound.spectrogram.

Parameters:

im2D numpy array

Image or Spectrogram

axaxis, optional, default is None

Draw the image on this specific axis. Allow multiple plots on the same figure.

kwargs, optional

• figsizetuple of integers, optional, default: (4,13)

  width, height in inches.

• titlestring, optional, default‘Spectrogram’

  title of the figure

• xlabelstring, optional, default‘Time [s]’

  label of the horizontal axis

• ylabelstring, optional, default‘Frequency [Hz]’

  label of the vertical axis

• xtickstuple of ndarrays, optional, defaultnone

  • ticks : array_like => A list of positions at which ticks should be placed. You can pass an empty list to disable yticks.

  • labels : array_like, optional => A list of explicit labels to place at the given locs.

• ytickstuple of ndarrays, optional, defaultnone

  • ticks : array_like => A list of positions at which ticks should be placed. You can pass an empty list to disable yticks.

  • labels : array_like, optional => A list of explicit labels to place at the given locs.

• cmapstring or Colormap object, optional, default is ‘gray’

  See https://matplotlib.org/examples/color/colormaps_reference.html in order to get all the existing colormaps examples: ‘hsv’, ‘hot’, ‘bone’, ‘tab20c’, ‘jet’, ‘seismic’, ‘viridis’…

• vmin, vmaxscalar, optional, default: None

  vmin and vmax are used in conjunction with norm to normalize luminance data. Note if you pass a norm instance, your settings for vmin and vmax will be ignored.

• extentlist of scalars [left, right, bottom, top], optional, default: None

  The location, in data-coordinates, of the lower-left and upper-right corners. If None, the image is positioned such that the pixel centers fall on zero-based (row, column) indices.

• nowboolean, optional, defaultTrue

  if True, display now. Cannot display multiple images. To display mutliple images, set now=False until the last call for the last image

• interpolationlist of string [None, ‘none’, ‘nearest’, ‘bilinear’,

  ‘bicubic’, ‘spline16’,’spline36’, ‘hanning’, ‘hamming’, ‘hermite’, ‘kaiser’, ‘quadric’,’catrom’, ‘gaussian’, ‘bessel’, ‘mitchell’, ‘sinc’, ‘lanczos’], optional, default : None

… and more, see matplotlib

Returns:

figFigure

The Figure instance

axAxis

The Axis instance

Examples

>>> w, fs = maad.sound.load('../data/cold_forest_daylight.wav') 
>>> Sxx_power,tn,fn,_ = maad.sound.spectrogram(w,fs)
>>> Lxx = maad.spl.power2dBSPL(Sxx_power, gain=42) # convert into dB SPL
>>> fig_kwargs = {'vmax': Lxx.max(),
                'vmin':0,
                'extent':(tn[0], tn[-1], fn[0], fn[-1]),
                'title':'Power spectrogram density (PSD) in dB SPL',
                'xlabel':'Time [s]',
                'ylabel':'Frequency [Hz]',
                }
>>> fig, ax = maad.util.plot2d(Lxx,interpolation=None,**fig_kwargs)