FFT spectrogram in log frequency space. How? I was reading a paper and the authors say that they extract FFT spectrograms and log-scale in frequency domain. I understand how the general spectrogram is computed, but how to make it log-scale in frequency domain? Or maybe there are libraries in Python, which already implement this one?
You can use either interpolation between FFT bins, or something like an MFCC triangular filter bank, except using equal delta_log spaced triangles instead of Mel-spaced triangles, or both.