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The Simplest Digital Filter (STM32 Implementation) - Phil's Lab #92

How to implement a simple digital filter (low-pass and high-pass exponential moving average (EMA)) on a real-time embedded system (STM32 + audio codec). Useful for noise reduction, removing DC offsets, and more in simple situations. Discussion on filter basics, advantages & disadvantages, theory, implementation in C, and real-time time- and frequency-domain tests.
  • 00:00Introduction
  • 01:15What We´ll Look At
  • 01:47EMA Filter Basics
  • 03:40Digital Filter Basics
  • 05:03Low-Pass Filter Theory
  • 08:36Filter Coefficient Effect on Frequency Response (Alpha)
  • 09:57Software Implementation in C (Low-Pass)
  • 13:11Low-Pass Filter Real-Time Test
  • 16:39High-Pass Filter Theory
  • 18:32Filter Coefficient Effect on Frequency Response (Beta)
  • 19:11Software Implementation in C (High-Pass)
  • 20:23High-Pass Filter Real-Time Test
  • 23:04Outro