Spectrogram

Spectrogram[list]
plots the spectrogram of list.

Spectrogram[list,n]
uses partitions of length n.

Spectrogram[list,n,d]
uses partitions with offset d.

Spectrogram[list,n,d,wfun]
applies a smoothing window wfun to each partition.

Spectrogram[sound,]
plots the spectrogram of sampled sound object.

Details and OptionsDetails and Options

  • Spectrogram[list] plots the magnitude of discrete Fourier transforms of partitions of list.
  • Spectrogram[list] uses partitions of length and offset Round[n/3], where m is Length[list].
  • If necessary, fixed padding is used on the right to make all the partitions the same size.
  • Spectrogram displays only the first half of the magnitude of the discrete Fourier transform due to the symmetry property of the transform.
  • In Spectrogram[list,n,d,wfun], the smoothing window wfun can be specified using a window function that will be sampled between and or a list of length n. The default window is DirichletWindow, which effectively does no smoothing.
  • Possible sound objects include:
  • SampledSoundList[{a1,a2,},r]amplitude levels given in a list
    SampledSoundFunction[f,n,r]amplitude levels generated by a function
    Sound[prims,]excluding SoundNote objects in prims
  • For multichannel sound objects, the spectrogram is computed over the sum of all channels.
  • Spectrogram accepts all ArrayPlot options with the following additions and changes:
  • AspectRatio1/3ratio of height to width
    ColorFunctionAutomatichow each cell should be colored
    DataReversedTruewhether to reverse the order of rows
    FrameTicksAutomaticwhat ticks to include on the frame
    SampleRateAutomaticsampling rate assumed for the input list
  • For the setting SampleRate->r and a list of length m, time is ranged from to , and the frequencies are in the range to r/2.
Introduced in 2012
(9.0)
| Updated in 2014
(10.0)