protect meters against weird float values

4 files changed, 12 insertions, 8 deletions

diff --git a/libs/ardour/iec1ppmdsp.cc b/libs/ardour/iec1ppmdsp.cc
index bed825048f..47e953f1ab 100644
--- a/libs/ardour/iec1ppmdsp.cc
+++ b/libs/ardour/iec1ppmdsp.cc
@@ -45,8 +45,8 @@ void Iec1ppmdsp::process (float *p, int n)
 {
     float z1, z2, m, t;
 
-    z1 = _z1;
-    z2 = _z2;
+    z1 = _z1 > 20 ? 20 : (_z1 < 0 ? 0 : _z1);
+    z1 = _z2 > 20 ? 20 : (_z2 < 0 ? 0 : _z2);
     m = _res ? 0: _m;
     _res = false;
 
diff --git a/libs/ardour/iec2ppmdsp.cc b/libs/ardour/iec2ppmdsp.cc
index 76862cccd2..bb934166fc 100644
--- a/libs/ardour/iec2ppmdsp.cc
+++ b/libs/ardour/iec2ppmdsp.cc
@@ -45,8 +45,8 @@ void Iec2ppmdsp::process (float *p, int n)
 {
     float z1, z2, m, t;
 
-    z1 = _z1;
-    z2 = _z2;
+    z1 = _z1 > 20 ? 20 : (_z1 < 0 ? 0 : _z1);
+    z1 = _z2 > 20 ? 20 : (_z2 < 0 ? 0 : _z2);
     m = _res ? 0: _m;
     _res = false;
 
diff --git a/libs/ardour/kmeterdsp.cc b/libs/ardour/kmeterdsp.cc
index 181378cf76..35c95c2daf 100644
--- a/libs/ardour/kmeterdsp.cc
+++ b/libs/ardour/kmeterdsp.cc
@@ -52,8 +52,8 @@ void Kmeterdsp::process (float *p, int n)
     float  s, z1, z2;
 
     // Get filter state.
-    z1 = _z1;
-    z2 = _z2;
+    z1 = _z1 > 50 ? 50 : (_z1 < 0 ? 0 : _z1);
+    z2 = _z2 > 50 ? 50 : (_z2 < 0 ? 0 : _z2);
 
     // Perform filtering. The second filter is evaluated
     // only every 4th sample - this is just an optimisation.
@@ -75,6 +75,8 @@ void Kmeterdsp::process (float *p, int n)
         z2 += 4 * _omega * (z1 - z2); // Update second filter.
     }
 
+    if (isnan(z1)) z1 = 0;
+    if (isnan(z2)) z2 = 0;
     // Save filter state. The added constants avoid denormals.
     _z1 = z1 + 1e-20f;
     _z2 = z2 + 1e-20f;
diff --git a/libs/ardour/vumeterdsp.cc b/libs/ardour/vumeterdsp.cc
index 67d48f6c54..a3d0ec23c1 100644
--- a/libs/ardour/vumeterdsp.cc
+++ b/libs/ardour/vumeterdsp.cc
@@ -43,8 +43,8 @@ void Vumeterdsp::process (float *p, int n)
 {
     float z1, z2, m, t1, t2;
 
-    z1 = _z1;
-    z2 = _z2;
+    z1 = _z1 > 20 ? 20 : (_z1 < -20 ? -20 : _z1);
+    z2 = _z2 > 20 ? 20 : (_z2 < -20 ? -20 : _z2);
     m = _res ? 0: _m;
     _res = false;
 
@@ -64,6 +64,8 @@ void Vumeterdsp::process (float *p, int n)
 	if (z2 > m) m = z2;
     }
 
+    if (isnan(z1)) z1 = 0;
+    if (isnan(z2)) z2 = 0;
     _z1 = z1;
     _z2 = z2 + 1e-10f;
     _m = m;