Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - A new constrained total variational deblurring model and its fast algorithm
AU - Williams, Bryan Michael
AU - Chen, Ke
AU - Harding, Simon P.
PY - 2015/6/29
Y1 - 2015/6/29
N2 - Although image intensities are non-negative quantities, imposing positivity is not always considered in restoration models due to a lack of simple and robust methods of imposing the constraint. This paper proposes a suitable exponential type transform and applies it to the commonly-used total variation model to achieve implicitly constrained solution (positivity at its lower bound and a prescribed intensity value at the upper bound). Further to establish convergence, a convex model is proposed through a relaxation of the transformed functional. Numerical algorithms are presented to solve the resulting non-linear partial differential equations. Test results show that the proposed method is competitive when compared with existing methods in simple cases and more superior in other cases.
AB - Although image intensities are non-negative quantities, imposing positivity is not always considered in restoration models due to a lack of simple and robust methods of imposing the constraint. This paper proposes a suitable exponential type transform and applies it to the commonly-used total variation model to achieve implicitly constrained solution (positivity at its lower bound and a prescribed intensity value at the upper bound). Further to establish convergence, a convex model is proposed through a relaxation of the transformed functional. Numerical algorithms are presented to solve the resulting non-linear partial differential equations. Test results show that the proposed method is competitive when compared with existing methods in simple cases and more superior in other cases.
KW - Alternating direction method of multipliers
KW - Box constraint
KW - Image deblurring
KW - Total variation
KW - Transforms
U2 - 10.1007/s11075-014-9904-2
DO - 10.1007/s11075-014-9904-2
M3 - Journal article
AN - SCOPUS:84929944019
VL - 69
SP - 415
EP - 441
JO - Numerical Algorithms
JF - Numerical Algorithms
SN - 1017-1398
IS - 2
ER -