How can I post process the data from a spectrogram?

I need to be able to post process the output from a given spectrogram. The steps: 1. Generate a spectrogram (which I know how to do) 2. Get the output from the spectrogram and post process it to client's specifications 3. Plot the resulting data/spectrogram.

Answer 1

[Walter Roberson]

This cannot be done in the general case. Client specifications are often impossible to meet.

Answer 2

[Greg Dionne]

The first output of SPECTROGRAM found in the Signal Processing Toolbox is an STFT.