I am trying to find the mean of all non zero voxels from an image which has 30 volumes. This is an image thats multiplied with a mask. 

I want to get this mean volume by volume. Is there any way to do it. 

fslstats gives me the mean for all 30 volumes. 

fslmeants ended up considering the zeroes voxels as well when I tried to mask and then find the mean. 

Do I have to split the image into 30 volumes to get this result? 

Thanks. 

- Anita