What's wrong with my STFT implementation?

1. What is the difference between FFT and STFT?
2. What is STFT spectrogram?
3. What is the use of STFT?

What is the difference between FFT and STFT?

FFT has a resolution of 2048 lines, Blackman window, and 50% overlap and STFT also has Block size 2048, FFT size 16K, Blackman window used, and 50% overlap. As we can see, STFT performs better with the same block size (but more calculated lines). We improved frequency resolution for the same amount of scooped data.

What is STFT spectrogram?

s = spectrogram( x ) returns the Short-Time Fourier Transform (STFT) of the input signal x . Each column of s contains an estimate of the short-term, time-localized frequency content of x . The magnitude squared of s is known as the spectrogram time-frequency representation of x [1].

What is the use of STFT?

The short-time Fourier transform (STFT) is used to analyze how the frequency content of a nonstationary signal changes over time. The magnitude squared of the STFT is known as the spectrogram time-frequency representation of the signal.