Resample PlugIn Help

The Resample PlugIn is useful for reducing the sample rate of a data stream in order to reduce network load.

It will take time series data in an RBNB channel, and either limit the data to a maximum number of samples (via the Max points per request parameter) by decimating the data, or it will apply a fixed decimation factor (through the Downsample factor parameter). If the sample limit requirement calls for a higher decimation factor than the fixed factor, the higher factor will be used.

For example, say the Resample PlugIn is started with a Downsample factor of 2 and a Max points value of 1000. If a request is then made for 1000 points, 500 points would be returned because the downsample factor of 2 would be used. If a request were made for 3000 points, 1000 points would be returned because the limit would establish a factor of 3. Note that only integer decimations are currently supported.

The Resample PlugIn also features an anti-aliasing capability. An 8 pole Butterworth low pass filter is used, with a breakpoint frequency at the Nyquist frequency of the downsampled data stream. This filter does have a noticeable startup transient.