The fundamental operation behind filtering
Convolution combines two signals to produce a third. In signal processing, it applies a filter (impulse response) to an input signal.
The Steps:
1. Flip the kernel (impulse response) horizontally
2. Shift it across the input signal
3. Multiply overlapping samples point-by-point
4. Sum the products to get one output sample
Applications: Smoothing, sharpening, edge detection, reverb, echo, blur effects