Function GrowConnCompsMask 

pub unsafe extern "C" fn GrowConnCompsMask(
    costs: *mut *mut c_void,
    flows: *mut *mut c_short,
    nrow: c_long,
    ncol: c_long,
    incrcosts: *mut *mut incrcostT,
    outfiles: *mut outfileT,
    params: *mut paramT,
) -> c_int

Grows contiguous regions demarcated by arcs whose residual costs are less than some threshold. Numbers the regions sequentially from 1. Writes out byte file of connected component mask, with 0 for any pixels not assigned to a component.