PHP第十课 PHP图像处理函数以及验证码实现-php手册-php.cn

Table of Contents

用户注册页面

Home

php教程

php手册

PHP第十课 PHP图像处理函数以及验证码实现

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 06, 2016 pm 07:55 PM

php function like Image Processing accomplish verify

如果你喜欢本博客,请访问本博客地址:http://blog.csdn.net/junzaivip 概要: gd库画图: 数学函数 PHP图片处理函数图片处理函数使用场景 1.验证码 2.缩放 3.裁剪 4.水印 gd库画图: 1.准备画布 2.准备涂料 3.画画 4.输出图片 5.保存图片 6.关闭画布 ?php //准

如果你喜欢本博客,请访问本博客地址:http://blog.csdn.net/junzaivip

概要:

gd库画图:

数学函数

PHP图片处理函数

图片处理函数使用场景

1.验证码
2.缩放
3.裁剪
4.水印

gd库画图:

1.准备画布
2.准备涂料
3.画画
4.输出图片
5.保存图片
6.关闭画布

<?php //准备画布

	$im = imagecreatetruecolor(500, 300);

	//准备涂料
	$black = imagecolorallocate($im, 0, 0, 0);

	$white = imagecolorallocate($im, 255, 255, 255);

	//背景填充成黑色
	imagefill($im,0,0, $black);

	//画一个矩形,填充成白色
	imagefilledellipse($im, 258, 151, 200, 200, $white);
	//输出到浏览器或保存起来
	header("content-type:image/png");
	//输出图片
	imagepng($im);

	//关闭画布
	imagedestroy($im);
?>

Copy after login

PHP图片处理函数
1.数学函数
2.图片处理函数

数学函数:
1.max();
2.min();
3.mt_rand();随机取一个数字

<?php echo	mt_rand(1,5);
?>

Copy after login

mt_rand随机取一个值

<?php //随机从一个数组中取一个值
$arr = array("a","b","c","d","e");

$rkey = mt_rand(0,count($arr)-1);

echo $arr[$rkey];
?>

Copy after login

4.ceil();天花板
5.floor();
6.round();四舍五入

<?php echo ceil(2.4);//3
	echo floor(2.4);//2
	echo round(2.4);//2
	echo round(2.6);//3

?>

Copy after login

6.pi(); //π 取圆周率

<?php &#160;
echo(pi());


echo M_PI;
?>

Copy after login

图片处理函数使用场景

1.验证码
2.缩放
3.裁剪
4.水印

PHP中穿件图像的五个步骤
1.准备画布
2.准备涂料
3.在画布上画图像或者文字
4.输出最终图像或曹村最终图像
5.释放画布资源

<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字
//如果不填充背景,默认是黑色
imageellipse($im,258,151,200,200,$white);


//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

绘制图像:
imagefill();
imagesetpixel();//画像素点
imageline();//画线
imagerectangle();//画一个矩形
imagepolygon();//画一个多边形
imageellipse();//画一个椭圆
imageare();画一个圆弧
imagechar();//水平的画一个字符
imagestring();//水平的画一行字符串

//画线
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字
//如果不填充背景,默认是黑色
imageline($im,0,0,500,300,$white);
imageline($im,0,300,500,0,$white);
imageline($im,0,150,500,150,$white);
imageline($im,250,0,250,300,$white);


//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

//添加干扰素
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字
//产生随机的点
for ($i=0; $i < 1000; $i++) { 

imagesetpixel($im,mt_rand(0,500),mt_rand(0,300),$white);

}
//产生随机的线

for ($j=0; $j < 100; $j++) { 
	imageline($im, mt_rand(0,500), mt_rand(0,300), mt_rand(0,500), mt_rand(0,300), $white);
}//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

//画矩形:
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);


//3.在画布上画图像或者文字
imagerectangle($im, 20, 20, 480, 280, $white);//
imagefilledrectangle($im, 20, 20, 480, 280, $white);//填充






//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

//imagepolygon 画多边形_画三角形
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字
$arr = array(
	250,20,
	60,240,
	440,240
	);
imagepolygon($im, $arr, 3, $white);


//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

画一个3D饼状图
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$red = imagecolorallocate($im, 255, 0, 0);
$grayred = imagecolorallocate($im, 255, 100, 100);
$green = imagecolorallocate($im, 0, 255, 0);
$blue = imagecolorallocate($im, 0, 0, 255);
$gray = imagecolorallocate($im, 200, 200, 200);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字
for ($i=0; $i < 10; $i++) { 
	imagefilledarc($im, 250, 150+$i, 200, 200, 0, 70, $gray,IMG_ARC_PIE);
	imagefilledarc($im, 250, 150+$i, 200, 200, 70, 190, $grayred,IMG_ARC_PIE);
	imagefilledarc($im, 250, 150+$i, 200, 200, 190, 270, $green,IMG_ARC_PIE);
	imagefilledarc($im, 250, 150+$i, 200, 200, 270, 360, $blue,IMG_ARC_PIE);

}
	imagefilledarc($im, 250, 150, 200, 200, 0, 70, $white,IMG_ARC_PIE);
	imagefilledarc($im, 250, 150, 200, 200, 70, 190, $red,IMG_ARC_PIE);
	imagefilledarc($im, 250, 150, 200, 200, 190, 270, $green,IMG_ARC_PIE);
	imagefilledarc($im, 250, 150, 200, 200, 270, 360, $blue,IMG_ARC_PIE);

//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

//写文字:
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$red = imagecolorallocate($im, 255, 0, 0);
$grayred = imagecolorallocate($im, 255, 100, 100);
$green = imagecolorallocate($im, 0, 255, 0);
$blue = imagecolorallocate($im, 0, 0, 255);
$gray = imagecolorallocate($im, 200, 200, 200);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字

$str= "PHP is very much";

imagestring($im, 5, 260, 160, $str, $green);
//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

//写单个字符:
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$red = imagecolorallocate($im, 255, 0, 0);
$grayred = imagecolorallocate($im, 255, 100, 100);
$green = imagecolorallocate($im, 0, 255, 0);
$blue = imagecolorallocate($im, 0, 0, 255);
$gray = imagecolorallocate($im, 200, 200, 200);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字

$str= "P";

imagechar($im, 5, 260, 160, $str, $green);
//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

//在图片上面写字
<?php //1.准备画布
$im = imagecreatetruecolor(500,300);
//2.准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$red = imagecolorallocate($im, 255, 0, 0);
$grayred = imagecolorallocate($im, 255, 100, 100);
$green = imagecolorallocate($im, 0, 255, 0);
$blue = imagecolorallocate($im, 0, 0, 255);
$gray = imagecolorallocate($im, 200, 200, 200);
$white = imagecolorallocate($im, 255, 255, 255);

//3.在画布上画图像或者文字

$str= "junzaivip";
$file = "E:/PHP/fonts/SIMYOU.TTF";
// $file = "fonts/SIMYOU.TTF";

imagettftext($im, 50, 0, 100, 200, $green, $file, $str);

//4.输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//5.释放画布资源
imagedestroy($im);
?>

Copy after login

PHP 验证码的设计

<?php //准备画布
$im = imagecreatetruecolor(100,50);
//准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$gray = imagecolorallocate($im, 200, 200, 200);

//填充背景
imagefill($im, 0, 0, $gray);

//文字坐标
$x = (100-4*20)/2 + 6;
$y = (50-20)/2 + 20;

//在画布上画图像或者文字

//把三个数组联系起来
$strarr = array_merge(range(1, 9),range(a, z),range(A, Z));

//打乱数组
shuffle($strarr);

//array_slice:取数组的前几位
//Join 将数组变成字符串,并且以第一个变量做分隔符
$str = join(&#39;&#39;,array_slice($strarr, 0,4));

$file = "E:/PHP/fonts/msyh.ttf";
// $file = "fonts/msyh.ttf";

imagettftext($im, 20, 0, $x, $y, $black, $file, $str);

//输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//释放画布资源
imagedestroy($im);
?>

Copy after login

php验证码设计:这里涉及到两个页面:index.php & reg.php
说明:

这个验证码版本只实现了验证图片的动态获取
前台注册页面的验证码和生成图片的验证码进行比较
验证码是由数字小写字母大写字母随机组成

index.php//实现用户的注册


	<title>reg</title>
	<style type="text/css">
	table{

		border-collapse: collapse;

	}

	</style>


<h2 id="用户注册页面">用户注册页面</h2>
<hr>

Copy after login

姓名:
密码:
验证码:

reg.php//用来验证验证码是否正确

<?php session_start();
	// echo $_POST[&#39;username&#39;];
	// echo $_POST[&#39;password&#39;];
	$code = strtolower($_POST[&#39;vcode&#39;]);

	// echo $code;

	// echo "<pre class="brush:php;toolbar:false">";
	// print_r($_SESSION);
	// echo "

Copy after login

"; $vstr = strtolower($_SESSION['vstr']); if ($code==$vstr) { //实现页面的跳转 echo "<script>location='http://www.baidu.com'</script>"; }else{ echo "<script>alert('验证码输入错误')</script>"; //echo "返回注册页面"; echo "<script>location='index.php'</script>"; } ?>
auth.php 用来生成验证码

<?php //开启session,开启session之前,不能有任何输出
session_start();


$width = 50;//验证码背景宽度
$height = 26;//验证码背景高速
$fonttype = 10;//验证码中字的大小
//准备画布
$im = imagecreatetruecolor($width,$height);
//准备涂料
$black = imagecolorallocate($im, 0, 0, 0);
$gray = imagecolorallocate($im, 200, 200, 200);

//填充背景
imagefill($im, 0, 0, $gray);

//文字坐标
$x = ($width-4*$fonttype)/2 +2;
$y = ($height-$fonttype)/2 + $fonttype;

//在画布上画图像或者文字

//把三个数组联系起来
$strarr = array_merge(range(1, 9),range(a, z),range(A, Z));

//打乱数组
shuffle($strarr);

//array_slice:取数组的前几位
//Join 将数组变成字符串,并且以第一个变量做分隔符
$str = join(&#39;&#39;,array_slice($strarr, 0,4));

//把$str放入session中,可方便所有页面使用
$_SESSION[&#39;vstr&#39;] = $str;

$file = "E:/PHP/fonts/msyh.ttf";
// $file = "fonts/msyh.ttf";

imagettftext($im, $fonttype, 0, $x, $y, $black, $file, $str);

//输出最终图像或保存最终图像
header("content-type:image/png");
imagepng($im);
//释放画布资源
imagedestroy($im);
?>

Copy after login

php验证码设计:
页面跳转:
1.php跳转
header("location:index.php");

2.js跳转(建议使用)
echo "<script>location = 'http://www.baidu.com'</script>";
echo "<script>location = 'index.php'</script>";

js弹窗:
echo '<script>alert("验证码有误,请重新输入")</script>';

2.缩放
获取图片的宽高
1.getimagesize(); //得到图片的大小可以直接通过图片("lyf.jpg")就可以获取图片的所有信息
2.imagesx();//得到图片的宽必须先获取图片的资源(imagecreatefromjpeg("lyf.jpg");),才能得到图片的信息
3.imagesy();//得到图片的高必须先获取图片的资源,才能得到图片的信息

已经存在的图片形成画布资源:
1.imagecreatefromjpeg();

<?php $im = imagecreatefromjpeg("lyf.jpg");

$x = imagesx($im);
$y = imagesy($im);

echo $x . $y;
exit;



header("content-type:image/jpeg");
imagejpeg($im);
?>

Copy after login

方法二获取图片的大小:

<?php $imgfile = "lyf.jpg";

$imgarr = getimagesize($imgfile);

echo "<pre class="brush:php;toolbar:false">";
print_r($imgarr);
echo "

Copy after login

"; exit; $im = imagecreatefromjpeg("lyf.jpg"); echo $x . $y; header("content-type:image/jpeg"); imagejpeg($im); ?>

图片缩放函数:
imagecopyresampled();

图片等比例缩放:

 <?php $imgfile = "lyf.jpg";

	//为了得到大图的宽高
	$imgarr = getimagesize($imgfile);

	$maxw = $imgarr[0];
	$maxh = $imgarr[1];
	$maxt = $imgarr[2];
	$maxm = $imgarr[&#39;mime&#39;];

	//为了把大图变为资源

	$im = imagecreatefromjpeg("lyf.jpg");

	//小图资源
	$minw = 100;
	$minh = 400;


	//等比例缩放
	if (($minw/$maxw)>($minh/$maxh)) {
		$rate =  $minh/$maxh ;		
	}else{
		$rate =  $minw / $maxw ;
	}

	$minw = floor($maxw * $rate);
	$minh = floor($maxh * $rate);
	$minim = imagecreatetruecolor($minw, $minh);

	//把大图缩放成小图
	imagecopyresampled($minim, $im, 0, 0, 0, 0, $minw, $minh, $maxw, $maxh);

	//小图输出
	header("content-type:{$maxm}");

	//判断类型
	switch ($maxt) {
		case 1:
			$imageout = "imagegif";
			break;
		case 2:
			$imageout = "imagejpeg";
			break;
		case 3:
			$imageout = "imagepng";
			break;
		
	}

	$imageout($minim);
	$minfilename = "s_".$imgfile;
	$imageout($minim,$minfilename);
	// imagejpeg($im);


	//释放资源
	imagedestroy($maxim);
	imagedestroy($minim);
	?>

Copy after login

图片裁剪函数:
imagecopyresampled();

图片水印函数:
imagecopy();

3.裁剪
4.水印

<?php $maxim = imagecreatefromjpeg("lyf.jpg");
	$minim = imagecreatefromjpeg("lyf.jpg");

	$maxw = imagesx($maxim);
	$maxh = imagesy($maxim);

	$minw = imagesx($minim);
	$minh = imagesy($minim);

	imagecopy($maxim, $minim, $maxw-$minw, $maxh-$minh, 0, 0, $minw, $minh);

	header("content-type:image/jpeg");

	imagejpeg($mamim);

 ?>

Copy after login

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress images for free

Clothoff.io

AI clothes remover

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Assassin's Creed Shadows: Seashell Riddle Solution

4 weeks ago By DDD

What's New in Windows 11 KB5054979 & How to Fix Update Issues

3 weeks ago By DDD

Where to find the Crane Control Keycard in Atomfall

4 weeks ago By DDD

Roblox: Dead Rails - How To Complete Every Challenge

1 months ago By DDD

How to fix KB5055523 fails to install in Windows 11?

2 weeks ago By DDD

Hot Tools

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Where is the login entrance for gmail email?

7742

Java Tutorial

1643

CakePHP Tutorial

1397

Laravel Tutorial

1291

PHP Tutorial

1234

Related knowledge

PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian Dec 24, 2024 pm 04:42 PM

PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati

7 PHP Functions I Regret I Didn't Know Before Nov 13, 2024 am 09:42 AM

If you are an experienced PHP developer, you might have the feeling that you’ve been there and done that already.You have developed a significant number of applications, debugged millions of lines of code, and tweaked a bunch of scripts to achieve op

How To Set Up Visual Studio Code (VS Code) for PHP Development Dec 20, 2024 am 11:31 AM

Visual Studio Code, also known as VS Code, is a free source code editor — or integrated development environment (IDE) — available for all major operating systems. With a large collection of extensions for many programming languages, VS Code can be c

Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

PHP Program to Count Vowels in a String Feb 07, 2025 pm 12:12 PM

A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total

How do you parse and process HTML/XML in PHP? Feb 07, 2025 am 11:57 AM

This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an

Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? Apr 03, 2025 am 12:03 AM

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

See all articles