Skip to content

Commit

Permalink
Fixed EAN13 bugs, added EAN8, unit tests and extended test projects
Browse files Browse the repository at this point in the history
  • Loading branch information
@Spelt
Spelt committed Nov 27, 2016
1 parent 53c2f9d commit 443f27d
Show file tree
Hide file tree
Showing 30 changed files with 1,455 additions and 791 deletions.
97 changes: 47 additions & 50 deletions Lib/Classes/1D Barcodes/ZXing.OneD.EAN13Reader.pas
View file
Original file line number Diff line number Diff line change
Expand Up @@ -15,7 +15,7 @@
* Original Authors: [email protected] (Daniel Switkin), Sean Owen and
* [email protected] (Alasdair Mackintosh)
* Delphi Implementation by K. Gossens
* Delphi Implementation by K. Gossens, E. Spelt
}

unit ZXing.OneD.EAN13Reader;
Expand Down Expand Up @@ -46,32 +46,32 @@ TEAN13Reader = class(TUPCEANReader)
// signified by using odd for '1', even for '2', even for '3', odd for '4',
// odd for '5', and even for '6'. See http://en.wikipedia.org/wiki/EAN-13
//
// Parity of next 6 digits
// Digit 0 1 2 3 4 5
// 0 Odd Odd Odd Odd Odd Odd
// 1 Odd Odd Even Odd Even Even
// 2 Odd Odd Even Even Odd Even
// 3 Odd Odd Even Even Even Odd
// 4 Odd Even Odd Odd Even Even
// 5 Odd Even Even Odd Odd Even
// 6 Odd Even Even Even Odd Odd
// 7 Odd Even Odd Even Odd Even
// 8 Odd Even Odd Even Even Odd
// 9 Odd Even Even Odd Even Odd
// Parity of next 6 digits
// Digit 0 1 2 3 4 5
// 0 Odd Odd Odd Odd Odd Odd
// 1 Odd Odd Even Odd Even Even
// 2 Odd Odd Even Even Odd Even
// 3 Odd Odd Even Even Even Odd
// 4 Odd Even Odd Odd Even Even
// 5 Odd Even Even Odd Odd Even
// 6 Odd Even Even Even Odd Odd
// 7 Odd Even Odd Even Odd Even
// 8 Odd Even Odd Even Even Odd
// 9 Odd Even Even Odd Even Odd
//
// Note that the encoding for '0' uses the same parity as a UPC barcode. Hence
// a UPC barcode can be converted to an EAN-13 barcode by prepending a 0.
//
// The encoding is represented by the following array, which is a bit pattern
// using Odd = 0 and Even = 1. For example, 5 is represented by:
//
// Odd Even Even Odd Odd Even
// Odd Even Even Odd Odd Even
// in binary:
// 0 1 1 0 0 1 == 0x19
// 0 1 1 0 0 1 == 0x19
//
class var
FIRST_DIGIT_ENCODINGS : TArray<Integer>;
decodeMiddleCounters : TArray<Integer>;
class var
FIRST_DIGIT_ENCODINGS: TArray<Integer>;
decodeMiddleCounters: TArray<Integer>;

/// <summary>
/// Based on pattern of odd-even ('L' and 'G') patterns used to encoded the explicitly-encoded
Expand All @@ -80,7 +80,7 @@ TEAN13Reader = class(TUPCEANReader)
/// </summary>
/// <param name="resultString">string to insert decoded first digit into</param>
/// <param name="lgPatternFound">int whose bits indicates the pattern of odd/even L/G patterns used to</param>
/// encode digits
/// encode digits
/// <return>-1 if first digit cannot be determined</return>
class function determineFirstDigit(const resultString: TStringBuilder;
const lgPatternFound: Integer): Boolean; static;
Expand All @@ -99,8 +99,8 @@ TEAN13Reader = class(TUPCEANReader)
/// horizontal offset of first pixel after the "middle" that was decoded or -1 if decoding could not complete successfully
/// </returns>
class function decodeMiddle(const row: IBitArray;
const startRange: TArray<Integer>;
const resultString: TStringBuilder): Integer; override;
const startRange: TArray<Integer>; const resultString: TStringBuilder)
: Integer; override;
public
/// <summary>
/// Initializes a new instance of the <see cref="TEAN13Reader"/> class.
Expand All @@ -122,10 +122,12 @@ implementation
constructor TEAN13Reader.Create();
begin
inherited;
SetLength(decodeMiddleCounters, 4);
end;

destructor TEAN13Reader.Destroy;
begin
decodeMiddleCounters := nil;
inherited;
end;

Expand All @@ -136,13 +138,10 @@ class function TEAN13Reader.decodeMiddle(const row: IBitArray;
bestMatch: Integer;
counter: Integer;
ending: Integer;
counters,
middleRange : TArray<Integer>;
rowOffset, x,
lgPatternFound: Integer;
counters, middleRange: TArray<Integer>;
rowOffset, x, lgPatternFound: Integer;
begin
Result := -1;

counters := decodeMiddleCounters;
counters[0] := 0;
counters[1] := 0;
Expand All @@ -157,33 +156,29 @@ class function TEAN13Reader.decodeMiddle(const row: IBitArray;
begin
if (not decodeDigit(row, counters, rowOffset, L_AND_G_PATTERNS, bestMatch))
then
exit;
resultString.Append('0' + IntToStr(bestMatch mod 10));
exit;
resultString.Append( IntToStr ( bestMatch mod 10) );
for counter in counters do
Inc(rowOffset, counter);
if (bestMatch >= 10)
then
lgPatternFound := lgPatternFound or (1 shl (5 - x));
if (bestMatch >= 10) then
lgPatternFound := lgPatternFound or (1 shl (5 - x));
Inc(x);
end;

if (not determineFirstDigit(resultString, lgPatternFound))
then
exit;
if (not determineFirstDigit(resultString, lgPatternFound)) then
exit;

middleRange := findGuardPattern(row, rowOffset, true, MIDDLE_PATTERN);
if (middleRange = nil)
then
exit;
if (middleRange = nil) then
exit;
rowOffset := middleRange[1];

x := 0;
while ((x < 6) and (rowOffset < ending)) do
begin
if (not decodeDigit(row, counters, rowOffset, L_PATTERNS, bestMatch))
then
exit;
resultString.Append('0' + IntToStr(bestMatch));
if (not decodeDigit(row, counters, rowOffset, L_PATTERNS, bestMatch)) then
exit;
resultString.Append(IntToStr(bestMatch));
for counter in counters do
Inc(rowOffset, counter);
Inc(x);
Expand All @@ -197,8 +192,8 @@ function TEAN13Reader.BarcodeFormat: TBarcodeFormat;
Result := TBarcodeFormat.EAN_13;
end;

class function TEAN13Reader.determineFirstDigit(
const resultString: TStringBuilder; const lgPatternFound: Integer): Boolean;
class function TEAN13Reader.determineFirstDigit(const resultString
: TStringBuilder; const lgPatternFound: Integer): Boolean;
var
d: Integer;
begin
Expand All @@ -207,7 +202,7 @@ class function TEAN13Reader.determineFirstDigit(
begin
if (lgPatternFound = FIRST_DIGIT_ENCODINGS[d]) then
begin
resultString.Insert(0, '0' + IntToStr(d));
resultString.Insert(0, IntToStr(d));
Result := true;
break;
end;
Expand All @@ -216,19 +211,21 @@ class function TEAN13Reader.determineFirstDigit(

class procedure TEAN13Reader.InitializeClass;
begin
FIRST_DIGIT_ENCODINGS := TArray<Integer>.Create($00, $0B, $0D, $0E, $13,
$19, $1C, $15, $16, $1A);
decodeMiddleCounters := TArray<Integer>.Create(0, 0, 0, 0);
FIRST_DIGIT_ENCODINGS := TArray<Integer>.Create($00, $0B, $0D, $0E, $13, $19,
$1C, $15, $16, $1A);
end;

class procedure TEAN13Reader.FinalizeClass;
begin
decodeMiddleCounters := nil;
FIRST_DIGIT_ENCODINGS := nil;
end;

initialization
TEAN13Reader.InitializeClass;

TEAN13Reader.InitializeClass;

finalization
TEAN13Reader.FinalizeClass;

TEAN13Reader.FinalizeClass;

end.
143 changes: 143 additions & 0 deletions Lib/Classes/1D Barcodes/ZXing.OneD.EAN8Reader.pas
View file
Original file line number Diff line number Diff line change
@@ -0,0 +1,143 @@
{
* Copyright 2008 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* Original Authors: [email protected] (Daniel Switkin), Sean Owen and
* [email protected] (Alasdair Mackintosh)
*
* Delphi Implementation by E. Spelt
}

unit ZXing.OneD.EAN8Reader;

interface

uses
System.SysUtils,
System.Generics.Collections,
System.Math,
ZXing.OneD.OneDReader,
ZXing.Common.BitArray,
ZXing.OneD.UPCEANReader,
ZXing.ReadResult,
ZXing.DecodeHintType,
ZXing.ResultPoint,
ZXing.BarcodeFormat;

type
/// <summary>
/// <p>Implements decoding of the EAN-8 format.</p>
/// </summary>
TEAN8Reader = class(TUPCEANReader)

private
class var decodeMiddleCounters: TArray<Integer>;
protected
class function decodeMiddle(const row: IBitArray;
const startRange: TArray<Integer>; const resultString: TStringBuilder)
: Integer; override;
public
function BarcodeFormat: TBarcodeFormat; override;
constructor Create; override;
destructor Destroy; override;
end;

implementation

function TEAN8Reader.BarcodeFormat: TBarcodeFormat;
begin
result:=TBarcodeFormat.EAN_8;
end;

constructor TEAN8Reader.Create;
begin
inherited;
SetLength(decodeMiddleCounters, 4);
end;

destructor TEAN8Reader.Destroy;
begin
decodeMiddleCounters := nil;
inherited;
end;

class function TEAN8Reader.DecodeMiddle(const row: IBitArray;
const startRange: TArray<Integer>;
const resultString: TStringBuilder): Integer;
var
ending, rowOffset, x, bestMatch: Integer;
counter: Integer;
counters, middleRange: TArray<Integer>;
begin
counters := self.decodeMiddleCounters;
counters[0] := 0;
counters[1] := 0;
counters[2] := 0;
counters[3] := 0;
ending := row.Size;
rowOffset := startRange[1];
x := 0;
while (((x < 4) and (rowOffset < ending))) do
begin
if (not TUPCEANReader.decodeDigit(row, counters, rowOffset,
TUPCEANReader.L_PATTERNS, bestMatch)) then
begin
Result := -1;
exit
end;

resultString.Append(IntToStr(bestMatch));

for counter in counters do
begin
inc(rowOffset, counter)
end;
inc(x)
end;

middleRange := TUPCEANReader.findGuardPattern(row, rowOffset, true,
TUPCEANReader.MIDDLE_PATTERN);
if (middleRange = nil) then
begin
Result := -1;
exit
end;

rowOffset := middleRange[1];
x := 0;
while (((x < 4) and (rowOffset < ending))) do
begin
if (not TUPCEANReader.decodeDigit(row, counters, rowOffset,
TUPCEANReader.L_PATTERNS, bestMatch)) then
begin
Result := -1;
exit
end;

resultString.Append(IntToStr(bestMatch));
for counter in counters do
begin
inc(rowOffset, counter)
end;

inc(x)
end;

Result := rowOffset;

end;



end.
Loading

0 comments on commit 443f27d

Please sign in to comment.