diff --git a/components/lazbarcodes/src/lbc_gs1.pas b/components/lazbarcodes/src/lbc_gs1.pas
index 494c06fa5..e32f1a6f9 100644
--- a/components/lazbarcodes/src/lbc_gs1.pas
+++ b/components/lazbarcodes/src/lbc_gs1.pas
@@ -1,13 +1,15 @@
-unit lbc_gs1;
-
 {
   Based on Zint (done by Robin Stuart and the Zint team)
     http://github.com/zint/zint
 
   and translation by TheUnknownOnes
     http://theunknownones.net
+    
+  Refactoring: W. Pamler
 }
 
+unit lbc_gs1;
+
 {$IFDEF FPC}
 {$mode objfpc}{$H+}
 {$ENDIF}
@@ -28,14 +30,9 @@ implementation
 uses 
   lbc_helper;
 
-{ This code does some checks on the integrity of GS1 data. It is not intended
-   to be bulletproof, nor does it report very accurately what problem was found
-   or where, but should prevent some of the more common encoding errors.
-   
-   wp: simplified a lot...}
-procedure itostr(var ai_string: String; ai_value: Integer);
+function Between(a, a1, a2: Integer): Boolean;
 begin
-  ai_string := FormatFloat('(00)', ai_value);
+  Result := (a >= a1) and (a <= a2);
 end;
 
 function gs1_verify(ASymbol: PZintSymbol; ASource: PByte; const src_len: Integer; 
@@ -190,7 +187,7 @@ begin
     if (data_length[i] = 0) then
     begin
       { No data for given AI }
-      strcpy(ASymbol^.errtxt, 'Empty data field in input data');
+      ASymbol^.SetErrorText('Empty data field in input data');
       Result := ERROR_INVALID_DATA; 
       exit;
     end;
@@ -215,47 +212,40 @@ begin
         error_latch := 2;
     end;
 
-    if ( ((ai_value[i] >= 100) and (ai_value[i] <= 179) ) or
-         ((ai_value[i] >= 1000) and (ai_value[i] <= 1799)) or
-         ((ai_value[i] >= 200) and (ai_value[i] <= 229)) or
-         ((ai_value[i] >= 2000) and (ai_value[i] <= 2299)) or
-         ((ai_value[i] >= 300) and (ai_value[i] <= 309)) or
-         ((ai_value[i] >= 3000) and (ai_value[i] <= 3099)) or
-         ((ai_value[i] >= 31) and (ai_value[i] <= 36)) or
-         ((ai_value[i] >= 310) and (ai_value[i] <= 369))
-       ) 
+    if Between(ai_value[i], 100, 179) or Between(ai_value[i], 1000, 1799) or 
+       Between(ai_value[i], 200, 229) or Between(ai_value[i], 2000, 2299) or
+       Between(ai_value[i], 300, 309) or Between(ai_value[i], 3000, 3099) or 
+       Between(ai_value[i],  31,  36) or Between(ai_value[i],  310,  369)
     then
-        error_latch := 2;
+      error_latch := 2;
     
-    if (ai_value[i] >= 3100) and (ai_value[i] <= 3699) then
+    if Between(ai_value[i], 3100, 3699) then
     begin
       if (data_length[i] <> 6) then
         error_latch := 1;
     end;
 
-    if ( ((ai_value[i] >= 370) and (ai_value[i] <= 379)) or
-        ((ai_value[i] >= 3700) and (ai_value[i] <= 3799)) ) 
-    then
+    if Between(ai_value[i], 370, 379) or Between(ai_value[i], 3700, 3799) then
       error_latch := 2;
       
-    if (ai_value[i] >= 410) and (ai_value[i] <= 415) then
+    if Between(ai_value[i], 410, 415) then
     begin
       if (data_length[i] <> 13) then
-      error_latch := 1;
+        error_latch := 1;
     end;
 
-    if ( ((ai_value[i] >= 4100) and (ai_value[i] <= 4199)) or
-         ((ai_value[i] >= 700) and (ai_value[i] <= 703)) or
-         ((ai_value[i] >= 800) and (ai_value[i] <= 810)) or
-         ((ai_value[i] >= 900) and (ai_value[i] <= 999)) or
-         ((ai_value[i] >= 9000) and (ai_value[i] <= 9999)) )
+    if Between(ai_value[i], 4100, 4199) or
+       Between(ai_value[i], 700, 703) or
+       Between(ai_value[i], 800, 810) or
+       Between(ai_value[i], 900, 999) or 
+       Between(ai_value[i], 9000, 9999)
     then
       error_latch := 2;
 
     if ((error_latch < 4) and (error_latch > 0)) then
     begin
       { error has just been detected: capture AI }
-      itostr(ai_string, ai_value[i]);
+      ai_string := FormatFloat('(00)', ai_value[i]);
       Inc(error_latch, 4);
     end;
   end;