tree 43492d547fc9a62038e740f885ddd69c73cf510e
parent e1c0770a49f5aad8053c204bb11c7c552020b684
author Jean-Marc Valin <jmvalin@jmvalin.ca> 1520869148 -0400
committer Jean-Marc Valin <jmvalin@jmvalin.ca> 1520870505 -0400
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Using a first-order filter for DC rejection

A second-order DC rejection filter is uselsss unless we have complex
poles. However, complex poles means we have to compute the filter as a
single pass (rather than two casdaded first-order filters), which has
numerical issues that would require a higher complexity to solve.
So rather than waste cycles with a second-order filter (with a longer
impulse response), we just go with a first-order filter.