Generate one-dimensional code using PHP

Generate a one-dimensional code using PHP. this code is from & nbsp; http://www.nixiaofeng.com/110.html&lt ;? Php $ code = $ _ GET ['code']; if ($ code! = "") {If (! Is_numeric ($ code) die ('input is not a number') generates a one-dimensional code using PHP
This code is from http://www.nixiaofeng.com/110.html

 13) die ('incorrect bar code length'); if (strlen ($ code) = 12) {// calculate the check bit $ lsum = 0; $ rsum = 0; for ($ I = 1; $ I <= strlen ($ code); $ I ++) {if ($ I % 2) {$ lsum + = (int) $ code [$ i-1];} else {$ rsum + = (int) $ code [$ i-1];} $ tsum = $ lsum + $ rsum * 3; $ chkdig = 10-($ tsum % 10); if ($ chkdig = 10) $ chkdig = 0; $ code. = $ chkdig;} // start of Definition $ start = '000000'; // define the abort operator $ end = '000000 '; // define the intermediate separator $ center = '20140901'; // define the left data code $ Guide = array (0 => 'aaaaa', 'ababab', 'aabbab ', 'aabbba ', 'ababab', 'abbaab', 'abbbaa', 'ababab', 'ababba', and 'abbaba'); // defines the left-side code, there are two types: "A" and "B": $ Lencode = array ("A" => array ('123456', '123456', '1234568 ', '123', '123', '123', '123', '123', '123'), "B" => array ('123', '123 ', '123', '123', '123', '123', '123', '123', '123', '123'); // define the right code, unified as "C" encoding $ Rencode = array ('20160301', '20160301', '20160301', '20160301', '20160301', '20160301 ', '20140901', '20160901', '20160901'); // encoding start code $ barcode = $ start; // Encode the left data bit for ($ I = 1; $ I <= 6; $ I ++) {$ barcode. = $ Lencode [$ Guide [$ code [0] [($ i-1)] [$ code [$ I];} // Encode the intermediate separator $ barcode. = $ center; // Encode the right data bit for ($ I = 7; $ I <13; $ I ++) {$ barcode. = $ Rencode [$ code [($ I)];} // code abort $ barcode. = $ end; // defines the width and height of each bar code unit, in pixels $ width = 2; $ height = 40; // defines the height increment of the start operator, stop operator, and intermediate separator $ increment = 10; // creates a square (× 95 is because the entire bar code contains 95 units, + 60 and + 30 are left blank borders around the bar code Image) $ img = ImageCreate ($ width * 95 + 60, $ height + 30 ); // currently, this square is transparent // "1" color (black) and "0" color (white) $ fg = ImageColorAllocate ($ img, 0, 0, 0); $ bg = ImageColorAllocate ($ img, 255,255,255); // fill the entire square ImageFilledRectangle ($ img, 0, 0, $ width * 95 + 60, $ height + 30, $ bg); // output the bar code Image for ($ x = 0; $ x
 
  
= 92) for the abort operator ($ x >=45 & $ x <50) for the intermediate separator // these three must be added to the if ($ x <4) | ($ x >=45 & $ x <50) | ($ x >=92) {$ increment = 10;} else {$ increment = 0 ;} // when the encoding value is "1", the output is black. when the encoding value is "0", the output is White if ($ barcode [$ x] = '1 ') {$ color = $ fg;} else {$ color = $ bg;} ImageFilledRectangle ($ img, ($ x * $ width) + 30, 5, ($ x + 1) * $ width + 29, $ height + $ increment, $ color);} ImageString ($ img, 5, 20, $ height + 5, $ code [0], $ fg); for ($ x = 0; $ x <6; $ x ++ ) {// Left-side ID: ImageString ($ img, 5, $ width * (8 + $ x * 6) + 30, $ height + 5, $ code [$ x + 1], $ fg); // ImageString ($ img, 5, $ width * (53 + $ x * 6) + 30, $ height + 5, $ code [$ x + 7], $ fg);} header ("Content-Type: image/jpeg"); ImageJPEG ($ img ,"", 100) ;}?>