diff --git a/lib/Subtitle/SSA/Event.pm b/lib/Subtitle/SSA/Event.pm
index d64eff0..5a20ea4 100644
--- a/lib/Subtitle/SSA/Event.pm
+++ b/lib/Subtitle/SSA/Event.pm
@@ -17,9 +17,9 @@ my %FIELDS = (
   end     => { type => 't', value =>  0,         name => 'End'     },
   style   => { type => 's', value => 'Default',  name => 'Style'   },
   name    => { type => 's', value => '',         name => 'Name'    },
-  marginl => { type => 's', value => '0000',     name => 'MarginL' },
-  marginr => { type => 's', value => '0000',     name => 'MarginR' },
-  marginv => { type => 's', value => '0000',     name => 'MarginV' },
+  marginl => { type => 'z', value => 0,          name => 'MarginL' },
+  marginr => { type => 'z', value => 0,          name => 'MarginR' },
+  marginv => { type => 'z', value => 0,          name => 'MarginV' },
   effect  => { type => 's', value => '',         name => 'Effect'  },
   text    => { type => 's', value => '',         name => 'Text'    },
 );
diff --git a/lib/Subtitle/SSA/Record.pm b/lib/Subtitle/SSA/Record.pm
index c20ce08..8fd8e74 100644
--- a/lib/Subtitle/SSA/Record.pm
+++ b/lib/Subtitle/SSA/Record.pm
@@ -51,10 +51,12 @@ sub parse_format_line {
 # formats:
 #  s - string, use as is
 #  d - decimal, no-zero pad
-#  b - boolean, 0 as false, -1 as true
 #  t - timing, like H:MM:SS.MSEC
 #  f - float, 6.01 or 6 if no fractional part
 #  x - hex-number, &H00AABBCC for ASS or decimal number for SSA
+# special cases:
+#  b - boolean, 0 as false, -1 as true (used in styles)
+#  z - same as decimal, but zero-padded to 4 digits (used in dialigue, for offset in pixels)
 sub parse {
   my ($self, $line, $format) = @_;
   $format //= $self->{_format};
@@ -78,6 +80,8 @@ sub parse {
     my $value = shift @values;
     if ($d->{type} eq 'x' and $value =~ m<&H([0-9a-f]{8})>oi) {
       $value = hex($1);
+    } elsif ($d->{type} eq 'z') {
+      $value = int($value);
     } elsif ($d->{type} eq 't') {
       $value = parse_timing($value);
       return $self->error("can't parse timing: $value")
@@ -102,6 +106,8 @@ sub to_string {
       $v = sprintf "%.2f", $v;
       # hack: make decimal from float if fractional part is zero after round up
       $v =~ s{\.00$}{}oi;
+    } elsif ($d->{type} eq 'z') {
+      $v = sprintf "%04d", $v;
     } elsif ($d->{type} eq 't') {
       my ($h, $m, $s, $ms) = make_timing($v);
       $v = sprintf("%d:%02d:%02d.%02d", $h, $m, $s, int($ms / 10));