Transforms a spectrogram into a form that's useful for speech recognition.
tf.raw_ops.Mfcc(
spectrogram,
sample_rate,
upper_frequency_limit=4000,
lower_frequency_limit=20,
filterbank_channel_count=40,
dct_coefficient_count=13,
name=None
)
Mel Frequency Cepstral Coefficients are a way of representing audio data that's been effective as an input feature for machine learning. They are created by taking the spectrum of a spectrogram (a 'cepstrum'), and discarding some of the higher frequencies that are less significant to the human ear. They have a long history in the speech recognition world, and https://en.wikipedia.org/wiki/Mel-frequency_cepstrum is a good resource to learn more.
Args |
|---|
spectrogram
Tensor of type float32.
Typically produced by the Spectrogram op, with magnitude_squared
set to true.
sample_rate
Tensor of type int32.
How many samples per second the source audio used.
upper_frequency_limit
float. Defaults to 4000.
The highest frequency to use when calculating the
ceptstrum.
lower_frequency_limit
float. Defaults to 20.
The lowest frequency to use when calculating the
ceptstrum.
filterbank_channel_count
int. Defaults to 40.
Resolution of the Mel bank used internally.
dct_coefficient_count
int. Defaults to 13.
How many output channels to produce per time slice.
name
Returns | |
|---|---|
A Tensor of type float32.
|