What is the value range of log magnitude spectrograms?

1. What is log magnitude spectrogram?
2. How is the magnitude of frequencies represented in a spectrogram?
3. How do you read a mel spectrogram?

What is log magnitude spectrogram?

The log-magnitude spectrogram is defined as the logarithmically scaled magnitude spectrum of a signal across time. The advantage of the log-magnitude spectrogram is that it shows how the energy distribution evolves.

How is the magnitude of frequencies represented in a spectrogram?

In a spectrogram representation plot — one axis represents the time, the second axis represents frequencies and the colors represent magnitude (amplitude) of the observed frequency at a particular time.

How do you read a mel spectrogram?

A mel spectrogram logarithmically renders frequencies above a certain threshold (the corner frequency). For example, in the linearly scaled spectrogram, the vertical space between 1,000 and 2,000Hz is half of the vertical space between 2,000Hz and 4,000Hz.