備忘錄_20160105(定位) 修改 回首頁

程式 2021-04-09 17:26:58 1617960418 100
captcha 核心

captcha 核心

captcha_core.php

<?php
  
  $iTotalWidth=130;
  $iTotalHeight=50;
  
  $strNumber=substr('0000' . rand(0,9999), -4);
  
  $fontfile = realpath('OpenSans-Bold.ttf');
  $image = imagecreatetruecolor($iTotalWidth,$iTotalHeight);
  $backgroundcolor = imagecolorallocate($image,60,60,60);
  $textColor = imagecolorallocate($image,155,155,155);
  
  $fontsize1=rand(23,30);
  $fontsize2=rand(23,30);
  
  imagefill($image,0,0,$backgroundcolor);
  
  for($i=0, $iMax=rand(5,10); $i<$iMax; $i++)
  {
    $lineColor = imagecolorallocate($image,rand(0,255),rand(0,255),rand(0,255));
    $x1=rand(0, $iTotalWidth);
    $x2=rand(0, $iTotalWidth);
    $y1=rand(0, $iTotalHeight);
    $y2=rand(0, $iTotalHeight);
    imageline($image, $x1, $y1, $x2, $y2, $lineColor);
  }
  
  imagettftext($image, $fontsize1, rand(-15,15), 20, 40, $textColor, $fontfile, substr($strNumber,0,2));
  imagettftext($image, $fontsize2, rand(-15,15), 65, 40, $textColor, $fontfile, substr($strNumber,2,2));
  
  header("Content-Type: image/png");
  imagepng($image);
  exit;
  
?>