Title :
Separation of Weak Reflection from a Single Superimposed Image
Author :
Qing Yan ; Yi Xu ; Xiaokang Yang ; Nguyen, Thin
Author_Institution :
Shanghai Key Lab. of Digital Media Process. & Transm., Shanghai Jiao Tong Univ., Shanghai, China
Abstract :
It is an inherently ill-posed problem to separate a single superimposed image into a reflection image and a transmission image. In this letter, a novel algorithm is proposed based on the prior knowledge that edges of weak reflection are always smoother than most edges of observed objects. To filter out the edges of weak reflection, an MRF-EM (Markov Random Field and Expectation Maximization) framework is proposed. In the MRF model, a data energy function is established based on the edge smoothness metric GPS (Gradient Profile Sharpness), and a spatial smoothness energy function is formulated using a weighted Potts model. Moreover, the parameters in the data energy function are updated using the EM algorithm. Experimental results demonstrate that the proposed algorithm can produce superior separation results with less residuals and color distortions compared to state-of-the-art methods.
Keywords :
Markov processes; edge detection; expectation-maximisation algorithm; gradient methods; image colour analysis; light reflection; light transmission; EM algorithm; GPS; MRF-EM framework; Markov random field and expectation maximization framework; data energy function; edge smoothness metric; gradient profile sharpness; reflection image; single superimposed image; spatial smoothness energy function; transmission image; weak reflection separation; weighted Potts model; Cameras; Global Positioning System; Image color analysis; Image edge detection; Image reconstruction; Robustness; Signal processing algorithms; Gradient profile sharpness; MRF-EM; reflection separation;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2014.2327071