Implementation of 2D Discrete Wavelet Transform by Number Theoretic Transform and 2D Overlap-Save Method

Figure 4

The full result of (4) computed by 2D overlap-save method, where 𝑙₁=𝑠₁𝑁^′+𝑁,  𝑚₁=𝑠₂𝑀^′+𝑀, and 𝑁^′+𝑙₂−1=𝑁<𝑙₁ and  𝑀^′+𝑚₂−1=𝑀<𝑚₁.