Extended Code 39 barcodes

Informations

Author: Emmanuel Havet
License: FPDF

Description

This script supports both standard and extended Code 39 barcodes. The extended mode gives access to the full ASCII range (from 0 to 127). The script also gives the possibility to add a checksum.

Code39(float x, float y, string code [, boolean ext [, boolean cks [, float w [, float h [, boolean wide]]]]])

x: abscissa
y: ordinate
code: barcode value
ext: indicates if extended mode must be used (true by default)
cks: indicates if a checksum must be appended (false by default)
w: width of a narrow bar (0.4 by default)
h: height of bars (20 by default)
wide: indicates if ratio between wide and narrow bars is high; if yes, ratio is 3, if no, it's 2 (true by default)

Source

<?php
require('fpdf.php');

class PDF_Code39 extends FPDF {

function Code39($x, $y, $code, $ext = true, $cks = false, $w = 0.4, $h = 20, $wide = true) {

    //Display code
    $this->SetFont('Arial', '', 10);
    $this->Text($x, $y+$h+4, $code);

    if($ext) {
        //Extended encoding
        $code = $this->encode_code39_ext($code);
    }
    else {
        //Convert to upper case
        $code = strtoupper($code);
        //Check validity
        if(!preg_match('|^[0-9A-Z. $/+%-]*$|', $code))
            $this->Error('Invalid barcode value: '.$code);
    }

    //Compute checksum
    if ($cks)
        $code .= $this->checksum_code39($code);

    //Add start and stop characters
    $code = '*'.$code.'*';

    //Conversion tables
    $narrow_encoding = array (
        '0' => '101001101101', '1' => '110100101011', '2' => '101100101011',
        '3' => '110110010101', '4' => '101001101011', '5' => '110100110101',
        '6' => '101100110101', '7' => '101001011011', '8' => '110100101101',
        '9' => '101100101101', 'A' => '110101001011', 'B' => '101101001011',
        'C' => '110110100101', 'D' => '101011001011', 'E' => '110101100101',
        'F' => '101101100101', 'G' => '101010011011', 'H' => '110101001101',
        'I' => '101101001101', 'J' => '101011001101', 'K' => '110101010011',
        'L' => '101101010011', 'M' => '110110101001', 'N' => '101011010011',
        'O' => '110101101001', 'P' => '101101101001', 'Q' => '101010110011',
        'R' => '110101011001', 'S' => '101101011001', 'T' => '101011011001',
        'U' => '110010101011', 'V' => '100110101011', 'W' => '110011010101',
        'X' => '100101101011', 'Y' => '110010110101', 'Z' => '100110110101',
        '-' => '100101011011', '.' => '110010101101', ' ' => '100110101101',
        '*' => '100101101101', '$' => '100100100101', '/' => '100100101001',
        '+' => '100101001001', '%' => '101001001001' );

    $wide_encoding = array (
        '0' => '101000111011101', '1' => '111010001010111', '2' => '101110001010111',
        '3' => '111011100010101', '4' => '101000111010111', '5' => '111010001110101',
        '6' => '101110001110101', '7' => '101000101110111', '8' => '111010001011101',
        '9' => '101110001011101', 'A' => '111010100010111', 'B' => '101110100010111',
        'C' => '111011101000101', 'D' => '101011100010111', 'E' => '111010111000101',
        'F' => '101110111000101', 'G' => '101010001110111', 'H' => '111010100011101',
        'I' => '101110100011101', 'J' => '101011100011101', 'K' => '111010101000111',
        'L' => '101110101000111', 'M' => '111011101010001', 'N' => '101011101000111',
        'O' => '111010111010001', 'P' => '101110111010001', 'Q' => '101010111000111',
        'R' => '111010101110001', 'S' => '101110101110001', 'T' => '101011101110001',
        'U' => '111000101010111', 'V' => '100011101010111', 'W' => '111000111010101',
        'X' => '100010111010111', 'Y' => '111000101110101', 'Z' => '100011101110101',
        '-' => '100010101110111', '.' => '111000101011101', ' ' => '100011101011101',
        '*' => '100010111011101', '$' => '100010001000101', '/' => '100010001010001',
        '+' => '100010100010001', '%' => '101000100010001');

    $encoding = $wide ? $wide_encoding : $narrow_encoding;

    //Inter-character spacing
    $gap = ($w > 0.29) ? '00' : '0';

    //Convert to bars
    $encode = '';
    for ($i = 0; $i< strlen($code); $i++)
        $encode .= $encoding[$code[$i]].$gap;

    //Draw bars
    $this->draw_code39($encode, $x, $y, $w, $h);
}

function checksum_code39($code) {

    //Compute the modulo 43 checksum

    $chars = array('0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
                            'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K',
                            'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V',
                            'W', 'X', 'Y', 'Z', '-', '.', ' ', '$', '/', '+', '%');
    $sum = 0;
    for ($i=0 ; $i<strlen($code); $i++) {
        $a = array_keys($chars, $code[$i]);
        $sum += $a[0];
    }
    $r = $sum % 43;
    return $chars[$r];
}

function encode_code39_ext($code) {

    //Encode characters in extended mode

    $encode = array(
        chr(0) => '%U', chr(1) => '$A', chr(2) => '$B', chr(3) => '$C',
        chr(4) => '$D', chr(5) => '$E', chr(6) => '$F', chr(7) => '$G',
        chr(8) => '$H', chr(9) => '$I', chr(10) => '$J', chr(11) => 'ŁK',
        chr(12) => '$L', chr(13) => '$M', chr(14) => '$N', chr(15) => '$O',
        chr(16) => '$P', chr(17) => '$Q', chr(18) => '$R', chr(19) => '$S',
        chr(20) => '$T', chr(21) => '$U', chr(22) => '$V', chr(23) => '$W',
        chr(24) => '$X', chr(25) => '$Y', chr(26) => '$Z', chr(27) => '%A',
        chr(28) => '%B', chr(29) => '%C', chr(30) => '%D', chr(31) => '%E',
        chr(32) => ' ', chr(33) => '/A', chr(34) => '/B', chr(35) => '/C',
        chr(36) => '/D', chr(37) => '/E', chr(38) => '/F', chr(39) => '/G',
        chr(40) => '/H', chr(41) => '/I', chr(42) => '/J', chr(43) => '/K',
        chr(44) => '/L', chr(45) => '-', chr(46) => '.', chr(47) => '/O',
        chr(48) => '0', chr(49) => '1', chr(50) => '2', chr(51) => '3',
        chr(52) => '4', chr(53) => '5', chr(54) => '6', chr(55) => '7',
        chr(56) => '8', chr(57) => '9', chr(58) => '/Z', chr(59) => '%F',
        chr(60) => '%G', chr(61) => '%H', chr(62) => '%I', chr(63) => '%J',
        chr(64) => '%V', chr(65) => 'A', chr(66) => 'B', chr(67) => 'C',
        chr(68) => 'D', chr(69) => 'E', chr(70) => 'F', chr(71) => 'G',
        chr(72) => 'H', chr(73) => 'I', chr(74) => 'J', chr(75) => 'K',
        chr(76) => 'L', chr(77) => 'M', chr(78) => 'N', chr(79) => 'O',
        chr(80) => 'P', chr(81) => 'Q', chr(82) => 'R', chr(83) => 'S',
        chr(84) => 'T', chr(85) => 'U', chr(86) => 'V', chr(87) => 'W',
        chr(88) => 'X', chr(89) => 'Y', chr(90) => 'Z', chr(91) => '%K',
        chr(92) => '%L', chr(93) => '%M', chr(94) => '%N', chr(95) => '%O',
        chr(96) => '%W', chr(97) => '+A', chr(98) => '+B', chr(99) => '+C',
        chr(100) => '+D', chr(101) => '+E', chr(102) => '+F', chr(103) => '+G',
        chr(104) => '+H', chr(105) => '+I', chr(106) => '+J', chr(107) => '+K',
        chr(108) => '+L', chr(109) => '+M', chr(110) => '+N', chr(111) => '+O',
        chr(112) => '+P', chr(113) => '+Q', chr(114) => '+R', chr(115) => '+S',
        chr(116) => '+T', chr(117) => '+U', chr(118) => '+V', chr(119) => '+W',
        chr(120) => '+X', chr(121) => '+Y', chr(122) => '+Z', chr(123) => '%P',
        chr(124) => '%Q', chr(125) => '%R', chr(126) => '%S', chr(127) => '%T');

    $code_ext = '';
    for ($i = 0 ; $i<strlen($code); $i++) {
        if (ord($code[$i]) > 127)
            $this->Error('Invalid character: '.$code[$i]);
        $code_ext .= $encode[$code[$i]];
    }
    return $code_ext;
}

function draw_code39($code, $x, $y, $w, $h) {

    //Draw bars

    for($i=0; $i<strlen($code); $i++) {
        if($code[$i] == '1')
            $this->Rect($x+$i*$w, $y, $w, $h, 'F');
    }
}
}
?>

Example

<?php
require('code39.php');

$pdf = new PDF_Code39();
$pdf->AddPage();
$pdf->Code39(60, 30, 'Code 39');
$pdf->Output();
?>
View the result here.

Download

ZIP | TGZ