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The following commit(s) were added to refs/heads/master by this push:
new 93312c6196 libdsp: update LP_FILTER comment
93312c6196 is described below
commit 93312c619677a47dc7042ae5d34db3a5d74068bf
Author: raiden00pl <[email protected]>
AuthorDate: Thu Oct 19 12:14:45 2023 +0200
libdsp: update LP_FILTER comment
add note about filter time constant (tau)
---
include/dsp.h | 1 +
include/dspb16.h | 1 +
2 files changed, 2 insertions(+)
diff --git a/include/dsp.h b/include/dsp.h
index 62672adfa1..b4b5c74037 100644
--- a/include/dsp.h
+++ b/include/dsp.h
@@ -102,6 +102,7 @@
* filter = T * (2*PI) * f_c
*
* phase shift = -arctan(f_in/f_c)
+ * time constant = -T / (ln(1 - filter))
*
* T - period at which the digital filter is being calculated
* f_in - input frequency of the filter
diff --git a/include/dspb16.h b/include/dspb16.h
index ee9f23e50a..1476e523b9 100644
--- a/include/dspb16.h
+++ b/include/dspb16.h
@@ -92,6 +92,7 @@
* filter = T * (2*PI) * f_c
*
* phase shift = -arctan(f_in/f_c)
+ * time constant = -T / (ln(1 - filter))
*
* T - period at which the digital filter is being calculated
* f_in - input frequency of the filter
