How does PHP realize the generation and identification of QR codes (code)

The content of this article is about how PHP realizes the generation and identification of QR codes (codes). It has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.

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Classification of QR codes

• linear stacked QR code

• Matrix QR code

Advantages and disadvantages of QR code

Advantages

• Large information capacity

• Wide encoding range

• Strong fault tolerance

• High decoding reliability

• Encryption measures can be introduced

• Low cost and easy to produce

Disadvantages

• QR code technology has become a new channel for the spread of mobile viruses and phishing websites

• Information leakage

Three major international standards currently popular

• PDF417: Does not support Chinese

• DM: Unpublished patent , need to pay patent fees

• QR CODE: patent disclosure, support Chinese

QR CODE error correction ability

• L level: approximately 7% of the data codewords can be corrected

• M level: approximately 15% of the data codewords can be error corrected

• Q level: approximately 25% of the data codewords can be corrected

• H level: approximately 30% of the data codewords can be error corrected

Prerequisite

• GD library

1. PHP generates QR CODE

• Official website: http://phpqrcode.sourceforge.net/

• Download source code: https://github.com/endroid/qr-code

Directory structure

##1. qrcode_create.php ps: Generate ordinary QR code

<?php
include_once "./qrcode/phpqrcode.php";/**
 * 参数:p1:二维码包含的内容 p2:输出的文件名 p3:容错级别 p4:大小 p5:外边距margin p6:保存路径
 * 在浏览器上直接生成一个二维码(内容为abc)
 */QRcode::png("abc");
QRcode::png("ABC",false,QR_ECLEVEL_L,10,5,false);/**
 * 生成文件到本地
 * 参数:p1:二维码包含的内容 p2:输出的文件名 p3:容错级别 p4:大小 p5:外边距margin p6:是否保存并打印(false 直接生成 true 生成且打印)
 * PS:$saveandprint源码的p6参数做了修改
 */QRcode::png("ABC","ABC.jpg",QR_ECLEVEL_H,10,2,false);

2. qrcode_logo.php ps: Generate QR code with Logo

<?php
/**
 * Created by PhpStorm.
 * User: user
 * Date: 2018/8/16
 * Time: 10:43
 */include "./qrcode/phpqrcode.php";$txt = "测试内容";
 $picPathAndName = "./pic/ABC.jpg";//二维码保存路径和名称
 $level = &#39;L&#39;;$size = 5;$is_logo = 1;//是否包含Logo 0否 1是
 $margin = 2;//边距
 $saveAndPrint = true;//是否保存，保存时，$picPathAndName设置为true//生成二维码图片
 QRcode::png($txt, $picPathAndName, $level, $size, $margin,$saveAndPrint);if($is_logo == 1){    
 $QR = $picPathAndName; //已经生成的原始二维码图
    $Logo = &#39;./pic/logo.png&#39;;    
    $Logo_re = &#39;./pic/test_logo.png&#39;;    
    $QR = imagecreatefromstring(file_get_contents($QR));    
    $Logo = imagecreatefromstring(file_get_contents($Logo));    
    $QR_width = imagesx($QR); //二维码图片宽度
    $QR_height = imagesy($QR); //二维码图片高度
    $logo_width = imagesx($Logo); //logo图片宽度
    $logo_height = imagesy($Logo); //logo图片高度
    $logo_qr_width = $QR_width / 5;    
    $scale = $logo_width / $logo_qr_width;    
    $logo_qr_height = $logo_height / $scale;    
    $from_width = ($QR_width - $logo_qr_width) / 2;
    imagecopyresampled($QR, $Logo, $from_width, $from_width, 0, 0, $logo_qr_width, $logo_qr_height, $logo_width, $logo_height);    
    //输出图片
    imagepng($QR, $Logo_re);
}

3. qrcode_vcard.php (Generate electronic signature)

• vCard format: https://zh.wikipedia.org/wiki/VCard

<?php/**
 * Created by PhpStorm.
 * User: user
 * Date: 2018/8/15
 * Time: 23:00
 */require_once "./qrcode/phpqrcode.php";/**
 * 生成电子签名
 * PS;使用微信扫描二维码
 */$content = &#39;BEGIN:VCARD&#39; . "\n";//起始标志
 $content .= &#39;VERSION:2.1&#39; . "\n";//当前版本
 $content .= &#39;N:周&#39; . "\n";//姓$content .= &#39;FN:勇&#39; . "\n";//名
 $content .= &#39;ORG:江苏东大集成电路系统有限公司&#39; . "\n";//公司名称
 $content .= &#39;TITLE:PHP研发程序员&#39; . "\n";//职位
 $content .= &#39;TEL;WORK;VOICE:0523-83623173&#39; . "\n";//工作电话
 $content .= &#39;ADR;WORK:;;高新区星火路#2;南京市;江苏省;225762;中国&#39; . "\n";//工作地址
 $content .= &#39;ADR;HOME:;;下圩镇王横村178号;兴化市;江苏省;225762;中国&#39; . "\n";//家庭地址(街道,地级市,省,邮编,国家)
 $content .= &#39;TEL;TYPE:18000001111&#39; . "\n";//移动电话
 $content .= &#39;EMAIL:123456@qq.com&#39; . "\n";//邮箱
 $content .= &#39;URL:www.baidu.com&#39; . "\n";//个人主页
 $content .= &#39;END:VCARD&#39; . "\n";//结束标志
 QRcode::png($content);

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• Source code address: https://github.com/jeromeetienne/jquery-qrcode

<!DOCTYPE html><html lang="en"><head>
    <meta charset="UTF-8">
    <title>Jquery生成二维码</title>
    <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
    <script type="text/javascript" src="./jquery-qrcode/jquery.qrcode.min.js"></script></head><body>
    <p id="qrcode"></p><script>
    //$(&#39;#qrcode&#39;).qrcode("this plugin is great");
    $(&#39;#qrcode&#39;).qrcode({width: 64,height: 64,text: "jason"});</script></body></html>

Environmental requirements, install the following extensions- ImageMagick
- zbar
- php-zbarcode

PHP recognizes QR codes (no need to install extensions). For preliminary testing, ordinary QR codes are OK. For QR codes with logo, the fault tolerance level needs to be set higher. qrReader class: https://github.com/baagee/php_QrReader

<?phpinclude_once(&#39;./qrReader/lib/QrReader.php&#39;);
$qrcode = new QrReader(&#39;./test_logo.png&#39;);  //图片路径
$text = $qrcode->text(); //返回识别后的文本
echo $text;

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