Wavelet Multiresolution Analysis

DWT decomposition — approximation & detail coefficients across scales


Signal & Wavelet

Key Equations

ψ_{j,k}(t) = 2^{j/2} ψ(2^j t − k)
Wf(j,k) = ⟨f, ψ_{j,k}⟩
Mallat: H(low-pass) + G(high-pass) → A_j + D_j
MRA: V₀ ⊃ V₁ ⊃ ... Vⱼ⊕Wⱼ=Vⱼ₋₁
Haar: ψ = χ[0,½) − χ[½,1)