# Overlap-windowing vs preserved information

When windowing non-overlapped segments of data stream, part of the data is being "ignored" at the boundaries of the segments due to the tapering of window functions (non-rectangular). Some information is lost in further processing.

My question is: for a given window function, does overlapping the segments by $50 \%$ preserve $100\%$ of the data stream information ?

Depending what do you mean by preserve $100\%$ of data stream information. Usually $50\%$ of overlap is enough and you are not loosing too much information. Amount of data within your observation window is definitely sufficient for further analysis.
• I am wondering if there are figures/numbers as to what percentage of the data is preserved, I heard some saying in the $70\%$ range, but I can't confirm this nor find any source. – Gilles Aug 17 '14 at 16:36