This script plots exponential moving average (EMA) of volume (line chart) together with spike threshold (area chart) offset by 1 bar. The idea is to detect sudden increase (spike) in volume when volume EMA crosses above the threshold which is calculated by multiplying a multiple in EMA of the previous bar.
This is used for setting alerts on changes of volume to get notified on sudden increase in volume. Custom alert included in the script and also available on Coinograph bot.