<?php
function getAuthImage($text) {
$im_x = 160;
$im_y = 40;
$im = imagecreatetruecolor($im_x,$im_y);
$text_c = ImageColorAllocate($im, mt_rand(0,100),mt_rand(0,100),mt_rand(0,100));
$tmpC0=mt_rand(100,255);
$tmpC1=mt_rand(100,255);
$tmpC2=mt_rand(100,255);
$buttum_c = ImageColorAllocate($im,$tmpC0,$tmpC1,$tmpC2);
imagefill($im, 16, 13, $buttum_c);
$font = 't1.ttf';
for ($i=0;$i<strlen($text);$i++)
{
$tmp =substr($text,$i,1);
$array = array(-1,1);
$p = array_rand($array);
$an = $array[$p]*mt_rand(1,10);//角度
$size = 28;
imagettftext($im, $size, $an, 15+$i*$size, 35, $text_c, $font, $tmp);
}
$distortion_im = imagecreatetruecolor ($im_x, $im_y);
imagefill($distortion_im, 16, 13, $buttum_c);
for ( $i=0; $i<$im_x; $i++) {
for ( $j=0; $j<$im_y; $j++) {
$rgb = imagecolorat($im, $i , $j);
if( (int)($i+20+sin($j/$im_y*2*M_PI)*10) <= imagesx($distortion_im)&& (int)($i+20+sin($j/$im_y*2*M_PI)*10) >=0 ) {
imagesetpixel ($distortion_im, (int)($i+10+sin($j/$im_y*2*M_PI-M_PI*0.1)*4) , $j , $rgb);
}
}
}
//加入干扰象素;
$count = 160;//干扰像素的数量
for($i=0; $i<$count; $i++){
$randcolor = ImageColorallocate($distortion_im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
imagesetpixel($distortion_im, mt_rand()%$im_x , mt_rand()%$im_y , $randcolor);
}
$rand = mt_rand(5,30);
$rand1 = mt_rand(15,25);
$rand2 = mt_rand(5,10);
for ($yy=$rand; $yy<=+$rand+2; $yy++){
for ($px=-80;$px<=80;$px=$px+0.1)
{
$x=$px/$rand1;
if ($x!=0)
{
$y=sin($x);
}
$py=$y*$rand2;
imagesetpixel($distortion_im, $px+80, $py+$yy, $text_c);
}
}
//设置文件头;
Header("Content-type: image/JPEG");
//以PNG格式将图像输出到浏览器或文件;
ImagePNG($distortion_im);
//销毁一图像,释放与image关联的内存;
ImageDestroy($distortion_im);
ImageDestroy($im);
}
function make_rand($length="32"){//验证码文字生成函数
$str="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
$result="";
for($i=0;$i<$length;$i++){
$num[$i]=rand(0,25);
$result.=$str[$num[$i]];
}
return $result;
}
//输出调用
$checkcode = make_rand(4);
session_start();//将随机数存入session中
$_SESSION['helloweba_gg']=strtolower($checkco