Interpolation interval and High Resolution

The interpolation interval sets how smoothly participants move on the map. Below 10 seconds it activates the High Resolution add-on.

GPS trackers report a position every few seconds at best. To move participants smoothly between those reports, RACEMAP calculates positions on a fixed time grid. The interpolation interval sets the spacing of that grid.

A shorter interval gives smoother movement in the replay and more frequent updates in the live map and the data APIs. A longer interval is coarser, but cheaper and easier on slow trackers.

You find the setting in the event editor under Advanced → Interpolation interval (in seconds).

Choosing an interval

The interval has to fit the report interval of your tracking devices. Speed in the visualization is calculated over a sliding window of ten interpolation intervals, and that window needs at least two coordinates from the interpolated grid to produce a value.

Set the interpolation interval to at least 20% of your device's report interval. A tracker reporting every 120 seconds needs an interpolation interval of 24 seconds or more.

Setting the interval far below the device's report interval does not add information. The positions in between are still interpolated from the same reports — the dots only move in smaller steps.

Changing the interval also adjusts the Live Delay Time so the live visualization stays smooth. See Tracking interval, runtime & battery for choosing the report interval on the device side.

High Resolution add-on

An interpolation interval below 10 seconds activates the High Resolution add-on. It is charged once per event cycle for as long as the interval stays below the threshold.

The editor asks you to confirm, and shows the current price, before applying an interval below 10 seconds.

Duplicating an event does not carry a high-resolution interval over. If the original event used an interval below 10 seconds, the copy starts at 10 seconds so that you do not book the add-on unintentionally. Set it again on the copy if you need it.

High Resolution is worth it when the movement itself is fast and close-range — cycling and motor sport on short circuits, rowing and sailing regattas, anything where participants are seconds apart and a coarse grid visibly lags behind. For road races, trail and endurance events an interval of 10 seconds or more is normally indistinguishable on the map.

Current prices are on the RACEMAP pricing page.