Optimized dual-frequency conductivity images with and without applying the optimization and denoising method. (a) and (e) Normalized noise standard deviation of the optimally weighted phase of H+and, respectively. (b) and (f) Reconstructed conductivity images without using the optimization and denoising method. (c) and (d) Reconstructed conductivity distributions at Larmor frequency using the optimized φ+,χwithout denoising and with the proposed denoising technique applying to ∇φ+,χ, respectively. (g) and (h) Reconstructed low-frequency conductivity distributions without denoising and with the proposed denoising technique applying to, respectively.