Can we have a function of Brownian motion that has finite length?

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My thought was to consider $\displaystyle\lim_{N\rightarrow\infty}\sum_{i=1}^N |B_{t_i}-B_{t_{i-1}}|$. I thought that such a limit might diverge to infinity a.s., and I found a paper that showed that by simple contradiction.

Can we smooth out Brownian path or apply a function to is so as to make it have finite length?

E.g. is there an $f$ such that $\displaystyle\lim_{N\rightarrow\infty}\sum_{i=1}^N |f(B_{t_i})-f(B_{t_{i-1}})|<\infty$ a.s.?