Time Subtract Average

This XTension calculates for each voxel a new intensity value, by subtracting the time-averaged intensity value from the initial intensity. It eliminates all motionless objects since the difference in intensities for motionless objects are negative values. There are two options: 1. The user can set all negative values to zero 2. To avoid these negative values and loss of data, any intensity which is zero or negative can be equal to absolute values