diff --git a/lib/Subtitle/BASE.pm b/lib/Subtitle/BASE.pm
index ffb9700..abb9b7e 100644
--- a/lib/Subtitle/BASE.pm
+++ b/lib/Subtitle/BASE.pm
@@ -25,6 +25,42 @@ sub chomp {
   return $line =~ s/(^\xEF\xBB\xBF|[\r\n]+$)//ogr;
 }
 
+sub parse_timing {
+  my ($self, $str) = @_;
+  my $time = 0.0;
+  return unless $str =~ m/(\d+):(\d+):(\d+)([.,])(\d+)/oi;
+  my ($hrs, $min, $sec, $delim, $msec) = ($1, $2, $3, $4, $5);
+  if ($msec < 0 or $msec > 999) {
+    $self->log(warn => "wrong mseconds part of timing: $msec");
+    return;
+  }
+  if ($sec < 0 or $sec > 59) {
+    $self->log(warn => "wrong seconds part of timing: $sec");
+    return;
+  }
+  if ($min < 0 or $min > 59) {
+    $self->log(warn => "wrong minutes part of timing: $sec");
+    return;
+  }
+  if ($hrs < 0) {
+    $self->log(warn => "wrong minutes part of timing: $sec");
+    return;
+  }
+  given (length("$msec")) {
+    when ("3") { $time += $msec * 0.001; }
+    when ("2") { $time += $msec * 0.01; }
+    when ("1") { $time += $msec * 0.1; }
+    default {
+      $self->log(error => "abnormal length of mseconds part");
+      return;
+    }
+  }
+  $time += $sec;
+  $time += $min * 60;
+  $time += $hrs * 60 * 60;
+  return $time;
+}
+
 sub trim {
   my ($self, $line) = @_;
   return unless defined $line;
diff --git a/lib/Subtitle/SRT.pm b/lib/Subtitle/SRT.pm
index ee08839..78a67ef 100644
--- a/lib/Subtitle/SRT.pm
+++ b/lib/Subtitle/SRT.pm
@@ -20,39 +20,6 @@ sub new {
   return bless($self, $class);
 }
 
-sub parse_timing {
-  my ($self, $str) = @_;
-  my $time = 0.0;
-  return unless $str =~ m/(\d+):(\d+):(\d+)([.,])(\d+)/oi;
-  my ($hrs, $min, $sec, $delim, $msec) = ($1, $2, $3, $4, $5);
-  if ($msec < 0 or $msec > 999) {
-    $self->log(warn => "wrong mseconds part of timing: $msec");
-    return;
-  }
-  if ($sec < 0 or $sec > 59) {
-    $self->log(warn => "wrong seconds part of timing: $sec");
-    return;
-  }
-  if ($min < 0 or $min > 59) {
-    $self->log(warn => "wrong minutes part of timing: $sec");
-    return;
-  }
-  if ($hrs < 0) {
-    $self->log(warn => "wrong minutes part of timing: $sec");
-    return;
-  }
-  given (length("$msec")) {
-    when ("3") { $time += $msec * 0.001; }
-    when ("2") { $time += $msec * 0.01; }
-    when ("1") { $time += $msec * 0.1; }
-    default { die("abnormal length of mseconds part"); }
-  }
-  $time += $sec;
-  $time += $min * 60;
-  $time += $hrs * 60 * 60;
-  return $time;
-}
-
 sub new_event { return +{ id => undef, timing => undef, text => undef }; }
 
 sub parse {
diff --git a/lib/Subtitle/SSA.pm b/lib/Subtitle/SSA.pm
index e057310..3119b1b 100644
--- a/lib/Subtitle/SSA.pm
+++ b/lib/Subtitle/SSA.pm
@@ -34,39 +34,6 @@ sub new {
   return bless($self, $class);
 }
 
-sub parse_timing {
-  my ($self, $str) = @_;
-  my $time = 0.0;
-  return unless $str =~ m/(\d+):(\d+):(\d+)([.,])(\d+)/oi;
-  my ($hrs, $min, $sec, $delim, $msec) = ($1, $2, $3, $4, $5);
-  if ($msec < 0 or $msec > 999) {
-    $self->log(warn => "wrong mseconds part of timing: $msec");
-    return;
-  }
-  if ($sec < 0 or $sec > 59) {
-    $self->log(warn => "wrong seconds part of timing: $sec");
-    return;
-  }
-  if ($min < 0 or $min > 59) {
-    $self->log(warn => "wrong minutes part of timing: $sec");
-    return;
-  }
-  if ($hrs < 0) {
-    $self->log(warn => "wrong minutes part of timing: $sec");
-    return;
-  }
-  given (length("$msec")) {
-    when ("3") { $time += $msec * 0.001; }
-    when ("2") { $time += $msec * 0.01; }
-    when ("1") { $time += $msec * 0.1; }
-    default { die("abnormal length of mseconds part"); }
-  }
-  $time += $sec;
-  $time += $min * 60;
-  $time += $hrs * 60 * 60;
-  return $time;
-}
-
 sub parse_header {
   my ($self, $linenum, $line) = @_;