# HG changeset patch
# User Chris Cannam
# Date 1443697633 -3600
# Node ID 14e0bbb06a9ac0f3f0befe8fdb1724c344bf0315
# Parent  bfd9acbcfd7ca11ab530d67950d82489c7cea10e
Comment

diff -r bfd9acbcfd7c -r 14e0bbb06a9a src/Filter.cpp
--- a/src/Filter.cpp	Thu Oct 01 11:51:54 2015 +0100
+++ b/src/Filter.cpp	Thu Oct 01 12:07:13 2015 +0100
@@ -27,6 +27,13 @@
     m_sz = int(params.b.size());
     m_order = m_sz - 1;
 
+    // We keep some empty space at the start of the buffer, and
+    // encroach gradually into it as we add individual sample
+    // calculations at the start. Then when we run out of space, we
+    // move the buffer back to the end and begin again. This is
+    // significantly faster than moving the whole buffer along in
+    // 1-sample steps every time.
+    
     m_offmax = 20;
     m_offa = m_offmax;
     m_offb = m_offmax;