Absolute phase estimation: adaptive local denoising and global unwrapping

The paper attacks absolute phase estimation with a two-step approach: the first step applies all adaptive local denoising scheme to the modulo-2 pi noisy phase: the second step applies a robust phase unwrapping algorithm to the denoised modulo-2 pi phase obtained ill the first step. The adaptive local modulo-2 pi, phase denoising is a new algorithm based oil local polynomial approximations. The zero-order and the first-order approximations of the phase are calculated in sliding windows of varying size. The. zero-order approximation is Used for. pointwise adaptive window size selection, whereas the first-order approximation is used to filter the phase in the obtained windows. For phase unwrapping, we apply the recently introduced robust (in the sense of discontinuity preserving) PUMA Unwrapping algorithm |IEEE Trans. Image Process. 16, 698 (2007)| to the denoised wrapped phase. Simulations give evidence that the proposed algorithm yields state-of-the-art performance, enabling strong noise attenuation while preserving image details. (C) 2008 Optical Society of America