Monday, 14 October 2024

SHORT-TIME FOURIER TRANSFORM

The Short-Time Fourier Transform (STFT) is applied to the acquired heart sound to analyze how the signal’s frequency content changes over time. Using the command stft (audio_filtered, Fs, 'Window', hamming(256), 'Overlap Length', 128), the filtered heart audio signal is divided into overlapping segments, with each segment transformed into the frequency domain. A Hamming window of size 256 is used to minimize spectral leakage, and an overlap of 128 samples ensures smooth transitions between segments. This time-frequency analysis is essential for identifying abnormalities such as murmurs, which may manifest as unusual frequency components during specific phases of the heart cycle. STFT provides a spectrogram, allowing visualization of frequency variations over time, making it a powerful tool for diagnosing heart conditions.

MATLAB CODE


WAVEFORM


By V Nidharshana, Mridula R, Smritti Bala R

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)

ARRHYTHMIA DETECTION

Arrhythmia detection in the MATLAB code involves analyzing the time intervals between consecutive heartbeats (S1 and S2 peaks) to identify i...

  • FEATURE EXTRACTION OF HEART SOUND
    FEATURE EXTRACTION AND VISUALIZATION OF HEART SOUND I n this step of heart sound analysis, a bandpass IIR filter is designed and applied to ...
  • SEGMENTATION OF HEART SOUNDS
    SEGMENTED HEART SOUNDS - S1, S2 PEAKS  In this step, the filtered heart sound signal is further analyzed by marking and segmenting key compo...
  • PEAK DETECTION
    In this stage of heart sound analysis, peak detection is performed on the envelope of the filtered heart sound signal. The  find peaks  func...