how to "Using your own matrix of fragment counts" with depth

[moonriver2002]

"In order to be able to use the filterSamples function, a “depth” column with the total sequencing depth must be included in the colData in the SummarizedExperiment object."

I already get counts file imputed with peaks. How can I get "depth" input into the "SummarizedExperiment object" so I can pass filterSamples function?

Thanks