Window size and overlap in spectrogram of a signal

Can anyone explain how to size a window and determining the overlap level to find the amplitude and threshold the resultant signal accordingly. This is used as a modern way of envelop detection and the threshold value will separate the valuable part from the unwanted part.

[Abhi Sundararaman]

For sizing a window, perhaps this post could be of use to you: https://www.mathworks.com/matlabcentral/answers/315739-how-to-decide-window-size-for-a-moving-average-filter

As for finding amplitude, you could just take the fft of the signal and then take the real portion of that, similar to how it is done in this post: https://www.mathworks.com/matlabcentral/answers/225440-how-to-extract-phase-and-amplitude-information-from-fft

As for the threshold, if you mean to find the peaks above a certain threshold, you could use the "findpeaks" function.