public FilterChain(Filter[] filters)
{
if (filters == null)
throw new ArgumentException("Filter array cannot be null.");
this.filters = filters;
return;
}
/// <summary>
/// Applies a nth-order Butterworth filter.
/// </summary>
/// <param name="factor"></param>
/// <param name="filterOrder"></param>
public DecimationFilter(int factor, int filterOrder, bool bidirectional)
{
this.factor = factor;
Util.Pair<double,double> cornerFreqs = new Util.Pair<double,double>(Math.PI / factor, 0.0);
FilterOrderSpec spec = FilterOrderSpec.CreateButterworthSpec(cornerFreqs, filterOrder, BandType.LowPass);
Filter antiAliasFilter = FilterFactory.CreateIirFilter(spec);
if(bidirectional)
antiAliasFilter = new BidirectionalFilter(antiAliasFilter);
Filter downSampleFilter = new DownSampleFilter(factor);
filter = new FilterChain(new Filter[] { antiAliasFilter, downSampleFilter });
return;
}
/// <summary>
/// Creates a bidirectional filter from any filter.
/// </summary>
public BidirectionalFilter(Filter filter)
{
this.filter = filter;
return;
}
