This time I will bring you the method of generating intricate (inclined, sinusoidal interference lines, pasting, rotation verification) verification codes, and generating intricate (tilt, sinusoidal interference lines, pasting, rotation verification) verification codes What are the precautions? The following is a practical case, let’s take a look.

Verification code used by many websites now is very easy to be automatically recognized by software. This article introduces a PHP-generated complex verification code that adds effects such as tilting, string interference lines, pasting, and rotation.

There are three common verification code methods that are not easily recognized by software:

1. Font variation (generally distorted through algorithms)

2. Paste fonts (the QQ verification code is represented here, it is still difficult to find online, crack the QQ verification code)

3 , interference lines, noise (this kind of identification is quite easy and can be automatically identified by the program)

As mentioned above, the first and second methods are more difficult to identify.

Specific implementation code:

<?php
/**
 *帶文字旋轉(zhuǎn)，傾斜，黏貼，加正弦干擾線驗(yàn)證碼*
 */
class Utils_Caption
{
	var $Width   = 60;      //圖片寬
	var $Height   = 30;      //圖片高
	var $Length   = 4;      //驗(yàn)證碼位數(shù)
	var $BgColor  = "#FFFFFF";  //背景色
	var $TFonts = array("font.ttf");
	var $TFontSize=array(17,20); //字體大小范圍
	var $TFontAngle=array(-20,20); //旋轉(zhuǎn)角度
	var $Chars  = "0123456789";     //驗(yàn)證碼范圍（字母數(shù)字）
	var $Code  = array();       //驗(yàn)證碼
	var $Image  = "";       //圖形對(duì)象
	var $FontColors=array(&#39;#f36161&#39;,&#39;#6bc146&#39;,&#39;#5368bd&#39;); //字體顏色,紅綠藍(lán)
	var $TPadden = 0.75;///字符間距,多少個(gè)字符
	var $Txbase = 5;///x軸兩邊距離
	var $Tybase =5 ;///y軸兩邊距離
	var $TLine =true; ///畫干擾線
	public function RandRSI() ///生成驗(yàn)證碼
	{
		$this->TFontAngle=range($this->TFontAngle[0],$this->TFontAngle[1]);
		$this->TFontSize=range($this->TFontSize[0],$this->TFontSize[1]);
		$arr=array();
		$Chars=$this->Chars;
		$TFontAngle=$this->TFontAngle;
		$TFontSize=$this->TFontSize;
		$FontColors=$this->FontColors;
		$code="";
		$font=dirname(FILE)."/font/".$this->TFonts[0];
		$charlen=strlen($Chars)-1;
		$anglelen=count($TFontAngle)-1;?//?角度范圍
		$fontsizelen=count($TFontSize)-1;?//?角度范圍
		$fontcolorlen=count($FontColors)-1;?//?角度范圍
		for($i=0;$i<$this->Length;$i++)?///得到字符與顏色
		{
			$char=$Chars[rand(0,$charlen)];?///得到字符
			$angle=$TFontAngle[rand(0,$anglelen)];?///旋轉(zhuǎn)角度
			$fontsize=$TFontSize[rand(0,$fontsizelen)];?///字體大小
			$fontcolor=$FontColors[rand(0,$fontcolorlen)];?///字體大小
			$bound=$this->_calculateTextBox($fontsize,$angle,$font,$char);?///得到范圍
			$arr[]=array($fontsize,$angle,$fontcolor,$char,$font,$bound);?///得到矩形框
			$code.=$char;
		}
		$this->Code=$arr;?//驗(yàn)證碼
		return?$code;
	}
	public?function?Draw()?///畫圖
	{
		if(empty($this->Code))?$this->RandRSI();
		$codes=$this->Code;?///用戶驗(yàn)證碼
		$wh=$this->_getImageWH($codes);
		$width=$wh[0];
		$height=$wh[1];?///高度
		$this->Width=$width;
		$this->Height=$height;
		$this->Image?=?imageCreate(?$width,?$height?);
		$image=$this->Image;
		$back?=?$this->_getColor2($this->_getColor(?$this->BgColor));?///背景顏色
		imageFilledRectangle($image,?0,?0,?$width,?$height,?$back);?///填充背景
		$TPadden=$this->TPadden;
		$basex=$this->Txbase;
		$color=null;
		foreach?($codes?as?$v)?///逐個(gè)畫字符
		{
			$bound=$v[5];
			$color=$this->_getColor2($this->_getColor($v[2]));
			imagettftext($image,?$v[0],?$v[1],?$basex,?$bound['height'],$color?,?$v[4],?$v[3]);
			$basex=$basex+$bound['width']*$TPadden-$bound['left'];///計(jì)算下一個(gè)左邊距
		}
		$this->TLine?$this->_wirteSinLine($color,$basex):null;?///畫干擾線
		header("Content-type:?image/png");
		imagepng(?$image);
		imagedestroy($image);
	}
	/**
	?*通過(guò)字體角度得到字體矩形寬度*
	?*
	?*?@param?int?$font_size?字體尺寸
	?*?@param?float?$font_angle?旋轉(zhuǎn)角度
	?*?@param?string?$font_file?字體文件路徑
	?*?@param?string?$text?寫入字符
	?*?@return?array?返回長(zhǎng)寬高
	?*/
	private?function?_calculateTextBox($font_size,?$font_angle,?$font_file,?$text)?{
		$box?=?imagettfbbox($font_size,?$font_angle,?$font_file,?$text);
		$min_x?=?min(array($box[0],?$box[2],?$box[4],?$box[6]));
		$max_x?=?max(array($box[0],?$box[2],?$box[4],?$box[6]));
		$min_y?=?min(array($box[1],?$box[3],?$box[5],?$box[7]));
		$max_y?=?max(array($box[1],?$box[3],?$box[5],?$box[7]));
		return?array(
		'left'?=>?($min_x?>=?-1)???-abs($min_x?+?1)?:?abs($min_x?+?2),
		'top'?=>?abs($min_y),
		'width'?=>?$max_x?-?$min_x,
		'height'?=>?$max_y?-?$min_y,
		'box'?=>?$box
		);
	}
	private?function?_getColor(?$color?)?//#ffffff
	{
		return?array(hexdec($color[1].$color[2]),hexdec($color[3].$color[4]),hexdec($color[5].$color[6]));
	}
	private?function?_getColor2(?$color?)?//#ffffff
	{
		return?imagecolorallocate?($this->Image,?$color[0],?$color[1],?$color[2]);
	}
	private?function?_getImageWH($data)
	{
		$TPadden=$this->TPadden;
		$w=$this->Txbase;
		$h=0;
		foreach?($data?as?$v)
		{
			$w=$w+$v[5]['width']*$TPadden-$v[5]['left'];
			$h=$h>$v[5]['height']?$h:$v[5]['height'];
		}
		return?array(max($w,$this->Width),max($h,$this->Height));
	}
	//畫正弦干擾線
	private?function?_wirteSinLine($color,$w)
	{
		$img=$this->Image;
		$h=$this->Height;
		$h1=rand(-5,5);
		$h2=rand(-1,1);
		$w2=rand(10,15);
		$h3=rand(4,6);
		for($i=-$w/2;$i<$w/2;$i=$i+0.1)
		{
			$y=$h/$h3*sin($i/$w2)+$h/2+$h1;
			imagesetpixel($img,$i+$w/2,$y,$color);
			$h2!=0?imagesetpixel($img,$i+$w/2,$y+$h2,$color):null;
		}
	}
}

DEMO code:

$rsi = new Utils_Caption();
$rsi->TFontSize=array(15,17);
$rsi->Width=50;
$rsi->Height=25;
$code?=?$rsi->RandRSI();
session_start();
$_SESSION["CHECKCODE"]?=?$code;
$rsi->Draw();

Running effect:

Everyone can Modify the corresponding values ??in the code to achieve the complexity you need

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!

Recommended reading:

php retains key value + merged array detailed explanation

How to remove duplicates in a two-dimensional array value

The above is the detailed content of Generate intricate (tilted, sinusoidal, pasted, rotated) verification codes. For more information, please follow other related articles on the PHP Chinese website!