Tag: matlab

    ECG Noise Removal Using Segmented-beat Modulation

    For some strange reason, I stumbled with a paper that I had downloaded long time ago. It explains a simple algorithm for removing artifacts in ECG signal. Since I have a short time-off after the submission of my PhD thesis (yey!), I thought it would be cool to actually code the algorithm and give it a go.

    Top: median cardiac cycle. Bottom: clean ECG signal in blue; (removed) motion artifact in gray.

    Read More

    ECG IIR Notch Filtering Using Transient Suppression

    Recently, I was going through my undergraduate lecture notes. I stumbled upon an exercise which I found interesting. The task consisted in implementing the algorithm proposed by Pei and Tseng, which uses vector projection to minimize the problem of transient values when applying an IIR notch filter to an ECG signal.

    Top: original ECG signal with AC interference noise. Middle: filtered ECG signal using a typical IIR notch filter. Bottom: filtered ECG signal using an IIR notch filter with the proposed transient suppression technique.

    Read More

    Generating a Binary Mask

    When working with images, selecting a specific region of an image to work with is quite common. Therefore I made a script that allows you to generate a mask with one or more regions of interest (ROIs). The shape of the ROIs can be rectangular, elliptic, (irregular) polygon, or free-hand drawn.

    Original Lena, generated mask, and masked Lena.

    Read More