PHP生成Gif图片验证码
先看效果图
字体及字体文件的路径需要在类中$fontfilepath及$fontfilename中设置。如：
private static $fontfilepath = "static/font/"; //相对地本代码文件的位置
private static $fontfilename = array("3.ttf");// array("1.ttf", "2.ttf", "3.ttf", "4.ttf", "5.ttf", "6.ttf", "7.ttf", "8.ttf"); //
完整代码如下：
<?php
/**
说明: 验证码生成类,支持生成gif图片验证码(带噪点，干扰线，网格，随机色背景，随机自定义字体，倾斜，gif动画）
服务端：
$mod = strtolower(isset($_request["mod"]) ? $_request["mod"] : "");
if($mod == "code"){
echo securitycode::draw(4, 1, 120, 30, 5, 10, 100, "secode");
die();
}
调用: <img src="/getcode.php?mod=code" onclick="this.src='/getcode.php?mod=code&r='+math.round(math.random(0)*1000)">
验证:
$reqcode = strtolower(isset($_request["secode"]) ? $_request["secode"] : ""); //请求的验证码
$sessioncode = strtolower(isset($_session["secode"]) ? $_session["secode"] : ""); //会话生成的验证码
if($reqcode != $sessioncode){
echo "安全验证码错误！";
die();
}
*/
$mod = strtolower(isset($_request["mod"]) ? $_request["mod"] : "");
if ($mod == "code") {
echo securitycode::draw(4, 15, 100, 27, 10, 2, 100, "secode");
die();
}
//安全验证码类
class securitycode {
private static $debug = 0;
private static $code = '';
private static $chars = 'bcdefhkmnrstuvwxyabcdefghkmnprstuvwxy34568';
//private static $chars = 'abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz01234567890';
private static $textgap = 20;
private static $textmargin = 5;
private static $fontfilepath = "static/font/"; //相对地本代码文件的位置
private static $fontfilename =array("3.ttf");// array("1.ttf", "2.ttf", "3.ttf", "4.ttf", "5.ttf", "6.ttf", "7.ttf", "8.ttf"); //
private static $img = 'gif89a'; //gif header 6 bytes
private static $buf = array();
private static $lop = 0;
private static $dis = 2;
private static $col = -1;
private static $img = -1;
/**
生成gif图片验证
@param int $l 验证码长度
@param int $f 生成gif图的帧数
@param int $w 宽度
@param int $h 高度
@param int $mixcnt 干扰线数
@param int $linegap 网格线间隔
@param int $noisycnt 澡点数
@param int $sessionname 验证码session名称
*/
public static function draw($l = 4, $f = 1, $w = 150, $h = 30, $mixcnt = 2, $linegap = 0, $noisycnt = 10, $sessionname = "code") {
ob_start();
ob_clean();
for ($i = 0; $i < $l; $i++) {
self::$code .= substr(self::$chars, mt_rand(0, strlen(self::$chars) - 1), 1);
}
if (!isset($_session))
session_start();
$_session[$sessionname] = strtolower(self::$code);
$bgrgb = array(rand(0, 255), rand(0, 255), rand(0, 255));
//生成一个多帧的gif动画
for ($i = 0; $i < $f; $i++) {
$img = imagecreate($w, $h);
//背景色
$bgcolor = imagecolorallocate($img, $bgrgb[0], $bgrgb[1], $bgrgb[2]);
imagecolortransparent($img, $bgcolor);
unset($bgcolor);
//添加噪点
$maxnoisy = rand(0, $noisycnt);
$noisycolor = imagecolorallocate($img, rand(0, 255), rand(0, 255), rand(0, 255));
for ($k = 0; $k <= $maxnoisy; $k++) {
imagesetpixel($img, rand(0, $w), rand(0, $h), $noisycolor);
}
//添加网格
if ($linegap > 0) {
for ($m = 0; $m < ($w / $linegap); $m++) { //竖线
imageline($img, $m * $linegap, 0, $m * $linegap, $h, $noisycolor);
}
for ($n = 0; $n < ($h / $linegap); $n++) { //横线
imageline($img, 0, $n * $linegap, $w, $n * $linegap, $noisycolor);
}
}
unset($noisycolor);
// 添加干扰线
for ($k = 0; $k < $mixcnt; $k++) {
$wr = mt_rand(0, $w);
$hr = mt_rand(0, $w);
$linecolor = imagecolorallocate($img, rand(0, 255), rand(0, 255), rand(0, 255));
imagearc($img, $w - floor($wr / 2), floor($hr / 2), $wr, $hr, rand(90, 180), rand(180, 270), $linecolor);
unset($linecolor);
unset($wr, $hr);
}
//第一帧忽略文字
if ($i != 0 || $f <= 1) {
//文字
$forecolor = imagecolorallocate($img, rand(0, 255), rand(0, 255), rand(0, 255));
for ($j = 0; $j < $l; $j++) {
$fontfile = self::$fontfilepath . self::$fontfilename[rand(0, count(self::$fontfilename) - 1)];
if (!file_exists($fontfile))
imagestring($img, 4, self::$textmargin + $j * self::$textgap, ($h - rand($h / 2, $h)), self::$code[$j], $forecolor);
else
imagettftext($img, rand(15, 18), rand(-15, 15), self::$textmargin + $j * self::$textgap, ($h - rand(7, 10)), $forecolor, $fontfile, self::$code[$j]);
}
unset($forecolor);
}
imagegif($img);
imagedestroy($img);
$imdata[] = ob_get_contents();
ob_clean();
}
unset($w, $h, $b);
if (self::$debug) {
echo $_session['code'];
echo '<pre>', var_dump($imdata), '</pre>';
die();
}
header('content-type:image/gif');
return self::creategif($imdata, 20);
unset($imdata);
}
private static function creategif($gif_src, $gif_dly = 10, $gif_lop = 0, $gif_dis = 0, $gif_red = 0, $gif_grn = 0, $gif_blu = 0, $gif_mod = 'bin') {
if (!is_array($gif_src) && !is_array($gif_tim)) {
throw new exception('error:' . __line__ . ',does not supported function for only one image!!');
die();
}
self::$lop = ($gif_lop > -1) ? $gif_lop : 0;
self::$dis = ($gif_dis > -1) ? (($gif_dis < 3) ? $gif_dis : 3) : 2;
self::$col = ($gif_red > -1 && $gif_grn > -1 && $gif_blu > -1) ? ($gif_red | ($gif_grn << 8) | ($gif_blu << 16)) : -1;
for ($i = 0, $src_count = count($gif_src); $i < $src_count; $i++) {
if (strtolower($gif_mod) == 'url') {
self::$buf[] = fread(fopen($gif_src[$i], 'rb'), filesize($gif_src[$i]));
} elseif (strtolower($gif_mod) == 'bin') {
self::$buf[] = $gif_src[$i];
} else {
throw new exception('error:' . __line__ . ',unintelligible flag (' . $gif_mod . ')!');
die();
}
if (!(substr(self::$buf[$i], 0, 6) == 'gif87a' or substr(self::$buf[$i], 0, 6) == 'gif89a')) {
throw new exception('error:' . __line__ . ',source ' . $i . ' is not a gif image!');
die();
}
for ($j = (13 + 3 * (2 << (ord(self::$buf[$i]{10}) & 0x07))), $k = true; $k; $j++) {
switch (self::$buf[$i]{$j}) {
case '!':
if ((substr(self::$buf[$i], ($j + 3), 8)) == 'netscape') {
throw new exception('error:' . __line__ . ',could not make animation from animated gif source (' . ($i + 1) . ')!');
die();
}
break;
case ';':
$k = false;
break;
}
}
}
self::addheader();
for ($i = 0, $count_buf = count(self::$buf); $i < $count_buf; $i++) {
self::addframes($i, $gif_dly);
}
self::$img .= ';';
return (self::$img);
}
private static function addheader() {
$i = 0;
if (ord(self::$buf[0]{10}) & 0x80) {
$i = 3 * (2 << (ord(self::$buf[0]{10}) & 0x07));
self::$img .= substr(self::$buf[0], 6, 7);
self::$img .= substr(self::$buf[0], 13, $i);
self::$img .= "!\377\13netscape2.0\3\1" . chr(self::$lop & 0xff) . chr((self::$lop >> 8) & 0xff) . "\0";
}
unset($i);
}
private static function addframes($i, $d) {
$l_str = 13 + 3 * (2 << (ord(self::$buf[$i]{10}) & 0x07));
$l_end = strlen(self::$buf[$i]) - $l_str - 1;
$l_tmp = substr(self::$buf[$i], $l_str, $l_end);
$g_len = 2 << (ord(self::$buf[0]{10}) & 0x07);
$l_len = 2 << (ord(self::$buf[$i]{10}) & 0x07);
$g_rgb = substr(self::$buf[0], 13, 3 * (2 << (ord(self::$buf[0]{10}) & 0x07)));
$l_rgb = substr(self::$buf[$i], 13, 3 * (2 << (ord(self::$buf[$i]{10}) & 0x07)));
$l_ext = "!\xf9\x04" . chr((self::$dis << 2) + 0) . chr(($d >> 0) & 0xff) . chr(($d >> 8) & 0xff) . "\x0\x0";
if (self::$col > -1 && ord(self::$buf[$i]{10}) & 0x80) {
for ($j = 0; $j < (2 << (ord(self::$buf[$i]{10}) & 0x07)); $j++) {
if (ord($l_rgb{3 * $j + 0}) == (self::$col >> 0) & 0xff && ord($l_rgb{3 * $j + 1}) == (self::$col >> 8) & 0xff && ord($l_rgb{3 * $j + 2}) == (self::$col >> 16) & 0xff) {
$l_ext = "!\xf9\x04" . chr((self::$dis << 2) + 1) . chr(($d >> 0) & 0xff) . chr(($d >> 8) & 0xff) . chr($j) . "\x0";
break;
}
}
}
switch ($l_tmp{0}) {
case '!':
$l_img = substr($l_tmp, 8, 10);
$l_tmp = substr($l_tmp, 18, strlen($l_tmp) - 18);
break;
case ',':
$l_img = substr($l_tmp, 0, 10);
$l_tmp = substr($l_tmp, 10, strlen($l_tmp) - 10);
break;
}
if (ord(self::$buf[$i]{10}) & 0x80 && self::$img > -1) {
if ($g_len == $l_len) {
if (self::compare($g_rgb, $l_rgb, $g_len)) {
self::$img .= ($l_ext . $l_img . $l_tmp);
} else {
$byte = ord($l_img{9});
$byte |= 0x80;
$byte &= 0xf8;
$byte |= (ord(self::$buf[0]{10}) & 0x07);
$l_img{9} = chr($byte);
self::$img .= ($l_ext . $l_img . $l_rgb . $l_tmp);
}
} else {
$byte = ord($l_img{9});
$byte |= 0x80;
$byte &= 0xf8;
$byte |= (ord(self::$buf[$i]{10}) & 0x07);
$l_img{9} = chr($byte);
self::$img .= ($l_ext . $l_img . $l_rgb . $l_tmp);
}
} else {
self::$img .= ($l_ext . $l_img . $l_tmp);
}
self::$img = 1;
}
private static function compare($g_block, $l_block, $len) {
for ($i = 0; $i < $len; $i++) {
if ($g_block{3 * $i + 0} != $l_block{3 * $i + 0} || $g_block{3 * $i + 1} != $l_block{3 * $i + 1} || $g_block{3 * $i + 2} != $l_block{3 * $i + 2}) {
return (0);
}
}
return (1);
}
}
用法在类开头的注释里。