A quick indicator in response to the product released on May 11th from BitMEX - a Daily settled index for bitcoin!
uses BVOL calculation from https://www.bitmex.com/app/index/.BVOL24H:
P = Bitfinex Last Price (taken at 5 minute intervals)
Stdev = Sample Standard Deviation
Ln = Natural Logarithm
Sqrt = Square Root
.BVOL Index = Stdev(Ln(P1/P0), Ln(P2/P1), ..., Ln(P288/P287))