diff --git a/doc/filters.texi b/doc/filters.texi
index 5f3d0906bd618f222653161d6012caae10258314..b8bf56de2ec9eeae6720d64b41be638ba82fa220 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -1954,7 +1954,7 @@ Set the timebase to use for the output frames timestamps.
 It is mainly useful for testing timebase configuration.
 
 It accepts in input an arithmetic expression representing a rational.
-The expression can contain the constants "PI", "E", "PHI", "AVTB" (the
+The expression can contain the constants "AVTB" (the
 default timebase), and "intb" (the input timebase).
 
 The default value for the input is "intb".
diff --git a/libavfilter/vf_settb.c b/libavfilter/vf_settb.c
index d0ac35c8f2842f59defe05962157f90fc6fda6ad..e74ee65cf2bed1636f9ba4b17c1522f617f2be16 100644
--- a/libavfilter/vf_settb.c
+++ b/libavfilter/vf_settb.c
@@ -31,18 +31,12 @@
 #include "internal.h"
 
 static const char *var_names[] = {
-    "E",
-    "PHI",
-    "PI",
     "AVTB",   /* default timebase 1/AV_TIME_BASE */
     "intb",   /* input timebase */
     NULL
 };
 
 enum var_name {
-    VAR_E,
-    VAR_PHI,
-    VAR_PI,
     VAR_AVTB,
     VAR_INTB,
     VAR_VARS_NB
@@ -73,9 +67,6 @@ static int config_output_props(AVFilterLink *outlink)
     int ret;
     double res;
 
-    settb->var_values[VAR_E]    = M_E;
-    settb->var_values[VAR_PHI]  = M_PHI;
-    settb->var_values[VAR_PI]   = M_PI;
     settb->var_values[VAR_AVTB] = av_q2d(AV_TIME_BASE_Q);
     settb->var_values[VAR_INTB] = av_q2d(inlink->time_base);