1. General Principles of Signal Processing
1.1. Basic Transformations
Last Updated: 21.03.2026All application interfaces use a common signal-processing system. Each element of this system can be enabled or disabled separately and has its own settings. The transformations...
1.2. Marking and Trim
Last Updated: 21.03.20261.2.1. Automatic Artifact Marking Purpose: Automatic detection of signal segments with amplitude outliers. How it works: Physiological explanation: The marking procedure is based on the idea...
1.3. CAR (Common Average Reference)
Last Updated: 21.03.2026Purpose: Removal of common artifacts present in all channels. Mathematical formula: avgElectrodes = (F8 + AF4 + AF3 + F7) / 4for each channel i: signal_i...
1.4. Denoise (Blink Artifact Suppression)
Last Updated: 21.03.2026Purpose: Removal of blink artifacts from the signal using wavelet processing. Method: Wavelet denoising using the Daubechies 4 (db4) wavelet. Parameters: How it works: Use case:...
1.5. Normalize
Last Updated: 21.03.2026Purpose: Bring the signal amplitude to a standard level. Formula:normalized_signal = 5 * signal / mean(abs(signal)) How it works: Use case: Standardizing amplitudes to compare signals...
1.6. IMF (Empirical Mode Decomposition)
Last Updated: 21.03.2026Purpose: Decompose the signal into intrinsic mode functions. Method: EMD (Empirical Mode Decomposition) with a maximum of 5 modes. How it works: Use cases: Physiological explanation...
1.7. Filtering
Last Updated: 21.03.2026Purpose: Isolate the signal in a specific frequency band. Method: FIR filter (Finite Impulse Response) using the Parks–McClellan algorithm (firpm). Filter parameters: Filter types: Available ranges...
1.8. Power vs Amplitude
Last Updated: 21.03.2026Purpose: Convert the signal into power or amplitude. Modes: Physiological explanation of power: Power equals the square of amplitude. It is a measure of the “energy”...
1.9. Epoch
Last Updated: 21.03.2026Purpose: Average the signal using a sliding window. Method: Sliding average using filtfilt (bidirectional filtering). Formula:epoch_length_samples = epoch_length_seconds * Fsb = ones(1, epoch_length_samples) / epoch_length_samplessmoothed_signal =...