1. A method, comprising: converting, by a system including a processor, an image sequence into an input matrix, wherein a column of the input matrix is a vectorized image related to the image sequence; approximating, by the system, the input matrix with a low rank matrix with a lower rank than the input matrix; detecting, by the system, one or more outliers of the input matrix; and decomposing, by the system, the input matrix as a sum of the low rank matrix, an intensity shift due to the one or more outliers, and random noise according to: 
 D=B+E +ε, where D is the input matrix, B is the low rank matrix, E is the intensity shift caused by the one or more outliers and ε is the random noise.