www.gusucode.com > Kodexplorer 可道云PHP在线文件管理系统源码程序 > kodexplorer_v4.32/app/sdks/MyCaptcha.class.php
<?php
class MyCaptcha{
var $keystring;
function __construct($length){
$alphabet = "0123456789abcdefghijklmnopqrstuvwxyz"; # do not change without changing font files!
$width = 140;
$height = 60;
$fluctuation_amplitude = $height/10;//上下起伏
$white_noise_density=1/10;//$white_noise_density=0; // no white noise
$black_noise_density=1/100;//$black_noise_density=0; // no black noise
$foreground_color = array(mt_rand(0,120), mt_rand(0,120), mt_rand(0,120));
$background_color = array(mt_rand(220,255), mt_rand(220,255), mt_rand(220,255));
$font_path = dirname(__FILE__).'/MyCaptcha_fonts/';
$fonts=array($font_path.'font_1.png',$font_path.'font_2.png',$font_path.'font_3.png');
$alphabet_length=strlen($alphabet);
do{
$this->keystring = $this->randString($length);
$font_file=$fonts[mt_rand(0, count($fonts)-1)];
$font=imagecreatefrompng($font_file);
imagealphablending($font, true);
$fontfile_width=imagesx($font);
$fontfile_height=imagesy($font)-1;
$font_metrics=array();
$symbol=0;
$reading_symbol=false;
// loading font
for($i=0;$i<$fontfile_width && $symbol<$alphabet_length;$i++){
$transparent = (imagecolorat($font, $i, 0) >> 24) == 127;
if(!$reading_symbol && !$transparent){
$font_metrics[$alphabet{$symbol}]=array('start'=>$i);
$reading_symbol=true;
continue;
}
if($reading_symbol && $transparent){
$font_metrics[$alphabet{$symbol}]['end']=$i;
$reading_symbol=false;
$symbol++;
continue;
}
}
$img=imagecreatetruecolor($width, $height);
imagealphablending($img, true);
$white=imagecolorallocate($img, 255, 255, 255);
$black=imagecolorallocate($img, 0, 0, 0);
imagefilledrectangle($img, 0, 0, $width-1, $height-1, $white);
$x=1;
$odd=mt_rand(0,1);
if($odd==0) $odd=-1;
for($i=0;$i<$length;$i++){
$m=$font_metrics[$this->keystring{$i}];
$y=(($i%2)*$fluctuation_amplitude - $fluctuation_amplitude/2)*$odd
+ mt_rand(-round($fluctuation_amplitude/3), round($fluctuation_amplitude/3))
+ ($height-$fontfile_height)/2;
$shift=1;
imagecopy($img, $font, $x-$shift, $y, $m['start'], 1, $m['end']-$m['start'], $fontfile_height);
$x+=$m['end']-$m['start']-$shift;
}
}while($x>=$width-10); // while not fit in canvas
//noise
$white=imagecolorallocate($font, 255, 255, 255);
$black=imagecolorallocate($font, 0, 0, 0);
for($i=0;$i<(($height-30)*$x)*$white_noise_density;$i++){
imagesetpixel($img, mt_rand(0, $x-1), mt_rand(10, $height-15), $white);
}
for($i=0;$i<(($height-30)*$x)*$black_noise_density;$i++){
imagesetpixel($img, mt_rand(0, $x-1), mt_rand(10, $height-15), $black);
}
$center=$x/2;
// credits. To remove, see configuration file
$img2=imagecreatetruecolor($width, $height);
$foreground=imagecolorallocate($img2, $foreground_color[0], $foreground_color[1], $foreground_color[2]);
$background=imagecolorallocate($img2, $background_color[0], $background_color[1], $background_color[2]);
imagefilledrectangle($img2, 0, 0, $width-1, $height-1, $background);
imagefilledrectangle($img2, 0, $height, $width-1, $height+12, $foreground);
$this->drawLine($img2,$width,$height);
// periods
$rand1=mt_rand(750000,1200000)/10000000;
$rand2=mt_rand(750000,1200000)/10000000;
$rand3=mt_rand(750000,1200000)/10000000;
$rand4=mt_rand(750000,1200000)/10000000;
// phases
$rand5=mt_rand(0,31415926)/10000000;
$rand6=mt_rand(0,31415926)/10000000;
$rand7=mt_rand(0,31415926)/10000000;
$rand8=mt_rand(0,31415926)/10000000;
// amplitudes
$rand9=mt_rand(330,420)/110;
$rand10=mt_rand(330,450)/100;
//wave distortion
for($x=0;$x<$width;$x++){
for($y=0;$y<$height;$y++){
$sx=$x+(sin($x*$rand1+$rand5)+sin($y*$rand3+$rand6))*$rand9-$width/2+$center+1;
$sy=$y+(sin($x*$rand2+$rand7)+sin($y*$rand4+$rand8))*$rand10;
if($sx<0 || $sy<0 || $sx>=$width-1 || $sy>=$height-1){
continue;
}else{
$color=imagecolorat($img, $sx, $sy) & 0xFF;
$color_x=imagecolorat($img, $sx+1, $sy) & 0xFF;
$color_y=imagecolorat($img, $sx, $sy+1) & 0xFF;
$color_xy=imagecolorat($img, $sx+1, $sy+1) & 0xFF;
}
if($color==255 && $color_x==255 && $color_y==255 && $color_xy==255){
continue;
}else if($color==0 && $color_x==0 && $color_y==0 && $color_xy==0){
$newred=$foreground_color[0];
$newgreen=$foreground_color[1];
$newblue=$foreground_color[2];
}else{
$frsx=$sx-floor($sx);
$frsy=$sy-floor($sy);
$frsx1=1-$frsx;
$frsy1=1-$frsy;
$newcolor=(
$color*$frsx1*$frsy1+
$color_x*$frsx*$frsy1+
$color_y*$frsx1*$frsy+
$color_xy*$frsx*$frsy
);
if($newcolor>255) $newcolor=255;
$newcolor=$newcolor/255;
$newcolor0=1-$newcolor;
$newred=$newcolor0*$foreground_color[0]+$newcolor*$background_color[0];
$newgreen=$newcolor0*$foreground_color[1]+$newcolor*$background_color[1];
$newblue=$newcolor0*$foreground_color[2]+$newcolor*$background_color[2];
}
imagesetpixel($img2, $x, $y, imagecolorallocate($img2, $newred, $newgreen, $newblue));
}
}
$this->showImage($img2);
}
public function getString(){
return $this->keystring;
}
private function randString($length){
$str = '';
$allowed_symbols = "23456789abcdegikpqsvxyz"; //without symbols (o=0, 1=l, i=j, t=f)
while(true){
$str = '';
for($i=0;$i<$length;$i++){
$str .= $allowed_symbols{mt_rand(0,strlen($allowed_symbols)-1)};
}
if(!preg_match('/cp|cb|ck|c6|c9|rn|rm|mm|co|do|cl|db|qp|qb|dp|ww/',$str)) break;
}
return $str;
}
private function frand(){
return mt_rand(0,9999)/10000;
}
private function drawLine(&$img,$width,$height){
$line_number = 5;
$color_from = 100;
for ($line = 0; $line < $line_number; ++ $line) {
$line_color = imagecolorallocate($img, mt_rand($color_from,255),
mt_rand($color_from, 255),mt_rand($color_from, 255));
$x = $width * (1 + $line) / ($line_number + 1);
$x += (0.5 - $this->frand()) * $width / $line_number;
$y = mt_rand($height * 0.1, $height * 0.9);
$theta = ($this->frand() - 0.5) * M_PI * 0.7;
$w = $width;
$len = mt_rand($w * 0.4, $w * 0.7);
$lwid = mt_rand(0, 2);
$k = $this->frand() * 0.6 + 0.2;
$k = $k * $k * 0.5;
$phi = $this->frand() * 6.28;
$step = 0.5;
$dx = $step * cos($theta);
$dy = $step * sin($theta);
$n = $len / $step;
$amp = 1.5 * $this->frand() / ($k + 5.0 / $len);
$x0 = $x - 0.5 * $len * cos($theta);
$y0 = $y - 0.5 * $len * sin($theta);
$ldx = round(- $dy * $lwid);
$ldy = round($dx * $lwid);
for ($i = 0; $i < $n; ++ $i) {
$x = $x0 + $i * $dx + $amp * $dy * sin($k * $i * $step + $phi);
$y = $y0 + $i * $dy - $amp * $dx * sin($k * $i * $step + $phi);
imagefilledrectangle($img, $x, $y, $x + $lwid, $y + $lwid,$line_color);
}
}
$allowed_symbols = "0123456789abcdefghijklmnopqrstuvwxyz";
for ($i = 0; $i < 20; $i++) {//写入随机字串
$char = $allowed_symbols[mt_rand(0,strlen($allowed_symbols)-1)];
$line_color = imagecolorallocate($img,
mt_rand($color_from,255),mt_rand($color_from, 255),mt_rand($color_from, 255));
imagechar($img,mt_rand(0,4),mt_rand(0,$width),rand(0,$height),$char,$line_color);
}
}
private function showImage(&$img){
ob_get_clean();
$out = ob_get_clean();//清除之前所有输出缓冲 TODO
header('Expires: Mon, 26 Jul 1997 05:00:00 GMT');
header('Cache-Control: no-store, no-cache, must-revalidate');
header('Cache-Control: post-check=0, pre-check=0', FALSE);
header('Pragma: no-cache');
if(function_exists("imagejpeg")){
header("Content-Type: image/jpeg");
imagejpeg($img, null,90);//图片质量
}else if(function_exists("imagegif")){
header("Content-Type: image/gif");
imagegif($img);
}else if(function_exists("imagepng")){
header("Content-Type: image/x-png");
imagepng($img);
}
}
}