The invention discloses an electrocardiographic
signal de-noising method based on adaptive threshold
wavelet transform. The method is characterized by comprising following steps: step 1: using the Mallat
algorithm, the
wavelet function sym6 and the number of
decomposition layers J are selected, and the noisy
ECG signal is decomposed by
wavelet to obtain approximate coefficients and detail coefficients; step 2: setting the threshold for adaptive detail coefficients at each layer and selecting the
threshold function; step 3: performing adaptive threshold
processing on the detail coefficients ofeach layer, removing
power frequency interference and myoelectric interference, and removing
baseline drift by
processing the approximation coefficients; step 4: performing
wavelet reconstruction on the electrocardiographic signals after
processing to obtain approximate optimal estimate value of signals. The method of the present invention makes full use of the multiresolution feature of the
wavelet transform. An adaptive threshold
selection method is provided. Different thresholds are used at each level to separate the
noise and
signal flexibly, improving the separability of
signal characteristics; in the three aspects of visual,
mean square error, and signal-to-
noise ratio, the effect is better than the traditional method, and the detailed information of the image is retained better, which has higher practical value.