<?php
/**
*ImageCode 生成包含验证码的GIF图片的函数
*@param $string 字符串
*@param $width 宽度
*@param $height 高度
**/
function ImageCode($string = '', $width = 75, $height = 25) {
$authstr = $string ? $string : ((time() % 2 == 0) ? mt_rand(1000, 9999) : mt_rand(10000, 99999));
$board_width = $width;
$board_height = $height;
// 生成一个32帧的GIF动画
for ($i = 0; $i < 32; $i ++) {
ob_start();
$image = imagecreate($board_width, $board_height);
imagecolorallocate($image, 0, 0, 0);
// 设定文字颜色数组
$colorList[] = ImageColorAllocate($image, 15, 73, 210);
$colorList[] = ImageColorAllocate($image, 0, 64, 0);
$colorList[] = ImageColorAllocate($image, 0, 0, 64);
$colorList[] = ImageColorAllocate($image, 0, 128, 128);
$colorList[] = ImageColorAllocate($image, 27, 52, 47);
$colorList[] = ImageColorAllocate($image, 51, 0, 102);
$colorList[] = ImageColorAllocate($image, 0, 0, 145);
$colorList[] = ImageColorAllocate($image, 0, 0, 113);
$colorList[] = ImageColorAllocate($image, 0, 51, 51);
$colorList[] = ImageColorAllocate($image, 158, 180, 35);
$colorList[] = ImageColorAllocate($image, 59, 59, 59);
$colorList[] = ImageColorAllocate($image, 0, 0, 0);
$colorList[] = ImageColorAllocate($image, 1, 128, 180);
$colorList[] = ImageColorAllocate($image, 0, 153, 51);
$colorList[] = ImageColorAllocate($image, 60, 131, 1);
$colorList[] = ImageColorAllocate($image, 0, 0, 0);
$fontcolor = ImageColorAllocate($image, 0, 0, 0);
$gray = ImageColorAllocate($image, 245, 245, 245);
$color = imagecolorallocate($image, 255, 255, 255);
$color2 = imagecolorallocate($image, 255, 0, 0);
imagefill($image, 0, 0, $gray);
$space = 15; // 字符间距
if ($i > 0) { // 屏蔽第一帧
$top = 0;
for ($k = 0; $k < strlen($authstr); $k ++) {
$colorRandom = mt_rand(0, sizeof($colorList) - 1);
$float_top = rand(0, 4);
$float_left = rand(0, 3);
imagestring($image, 6, $space * $k, $top + $float_top, substr($authstr, $k, 1), $colorList[$colorRandom]);
}
}
for ($k = 0; $k < 20; $k ++) {
$colorRandom = mt_rand(0, sizeof($colorList) - 1);
imagesetpixel($image, rand() % 70, rand() % 15, $colorList[$colorRandom]);
}
// 添加干扰线
for ($k = 0; $k < 3; $k ++) {
$colorRandom = mt_rand(0, sizeof($colorList) - 1);
$todrawline = 1;
if ($todrawline) {
imageline($image, mt_rand(0, $board_width), mt_rand(0, $board_height), mt_rand(0, $board_width), mt_rand(0, $board_height), $colorList[$colorRandom]);
} else {
$w = mt_rand(0, $board_width);
$h = mt_rand(0, $board_width);
imagearc($image, $board_width - floor($w / 2), floor($h / 2), $w, $h, rand(90, 180), rand(180, 270), $colorList[$colorRandom]);
}
}
imagegif($image);
imagedestroy($image);
$imagedata[] = ob_get_contents();
ob_clean();
++ $i;
}
$gif = new GIFEncoder($imagedata);
Header('Content-type:image/gif');
echo $gif->GetAnimation();
}
/**
* *GIFEncoder类
* *
*/
class GIFEncoder {
var $GIF = "GIF89a"; /* GIF header 6 bytes */
var $VER = "GIFEncoder V2.06"; /* Encoder version */
var $BUF = Array();
var $LOP = 0;
var $DIS = 2;
var $COL = - 1;
var $IMG = - 1;
var $ERR = Array(
'ERR00' => "Does not supported function for only one image!",
'ERR01' => "Source is not a GIF image!",
'ERR02' => "Unintelligible flag ",
'ERR03' => "Could not make animation from animated GIF source"
);
function GIFEncoder($GIF_src, $GIF_dly = 100, $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)) {
printf("%s: %s", $this->VER, $this->ERR['ERR00']);
exit(0);
}
$this->LOP = ($GIF_lop > - 1) ? $GIF_lop : 0;
$this->DIS = ($GIF_dis > - 1) ? (($GIF_dis < 3) ? $GIF_dis : 3) : 2;
$this->COL = ($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") {
$this->BUF[] = fread(fopen($GIF_src[$i], "rb"), filesize($GIF_src[$i]));
} elseif (strToLower($GIF_mod) == "bin") {
$this->BUF[] = $GIF_src[$i];
} else {
printf("%s: %s(%s)!", $this->VER, $this->ERR['ERR02'], $GIF_mod);
exit(0);
}
if (substr($this->BUF[$i], 0, 6) != "GIF87a" && substr($this->BUF[$i], 0, 6) != "GIF89a") {
printf("%s: %d %s", $this->VER, $i, $this->ERR['ERR01']);
exit(0);
}
for ($j = (13 + 3 * (2 << (ord($this->BUF[$i]{10}) & 0x07))), $k = TRUE; $k; $j ++) {
switch ($this->BUF[$i]{$j}) {
case "!" :
if ((substr($this->BUF[$i], ($j + 3), 8)) == "NETSCAPE") {
printf("%s: %s(%s source)!", $this->VER, $this->ERR['ERR03'], ($i + 1));
exit(0);
}
break;
case ";" :
$k = FALSE;
break;
}
}
}
GIFEncoder::GIFAddHeader();
for ($i = 0, $count_buf = count($this->BUF); $i < $count_buf; $i ++) {
GIFEncoder::GIFAddFrames($i, $GIF_dly[$i]);
}
GIFEncoder::GIFAddFooter();
}
function GIFAddHeader() {
$cmap = 0;
if (ord($this->BUF[0]{10}) & 0x80) {
$cmap = 3 * (2 << (ord($this->BUF[0]{10}) & 0x07));
$this->GIF .= substr($this->BUF[0], 6, 7);
$this->GIF .= substr($this->BUF[0], 13, $cmap);
$this->GIF .= "!\377\13NETSCAPE2.0\3\1" . GIFEncoder::GIFWord($this->LOP) . "\0";
}
}
function GIFAddFrames($i, $d) {
$Locals_str = 13 + 3 * (2 << (ord($this->BUF[$i]{10}) & 0x07));
$Locals_end = strlen($this->BUF[$i]) - $Locals_str - 1;
$Locals_tmp = substr($this->BUF[$i], $Locals_str, $Locals_end);
$Global_len = 2 << (ord($this->BUF[0]{10}) & 0x07);
$Locals_len = 2 << (ord($this->BUF[$i]{10}) & 0x07);
$Global_rgb = substr($this->BUF[0], 13, 3 * (2 << (ord($this->BUF[0]{10}) & 0x07)));
$Locals_rgb = substr($this->BUF[$i], 13, 3 * (2 << (ord($this->BUF[$i]{10}) & 0x07)));
$Locals_ext = "!\xF9\x04" . chr(($this->DIS << 2) + 0) . chr(($d >> 0) & 0xFF) . chr(($d >> 8) & 0xFF) . "\x0\x0";
if ($this->COL > - 1 && ord($this->BUF[$i]{10}) & 0x80) {
for ($j = 0; $j < (2 << (ord($this->BUF[$i]{10}) & 0x07)); $j ++) {
if (ord($Locals_rgb{3 * $j + 0}) == ($this->COL >> 0) & 0xFF && ord($Locals_rgb{3 * $j + 1}) == ($this->COL >> 8) & 0xFF && ord($Locals_rgb{3 * $j + 2}) == ($this->COL >> 16) & 0xFF) {
$Locals_ext = "!\xF9\x04" . chr(($this->DIS << 2) + 1) . chr(($d >> 0) & 0xFF) . chr(($d >> 8) & 0xFF) . chr($j) . "\x0";
break;
}
}
}
switch ($Locals_tmp{0}) {
case "!" :
$Locals_img = substr($Locals_tmp, 8, 10);
$Locals_tmp = substr($Locals_tmp, 18, strlen($Locals_tmp) - 18);
break;
case "," :
$Locals_img = substr($Locals_tmp, 0, 10);
$Locals_tmp = substr($Locals_tmp, 10, strlen($Locals_tmp) - 10);
break;
}
if (ord($this->BUF[$i]{10}) & 0x80 && $this->IMG > - 1) {
if ($Global_len == $Locals_len) {
if (GIFEncoder::GIFBlockCompare($Global_rgb, $Locals_rgb, $Global_len)) {
$this->GIF .= ($Locals_ext . $Locals_img . $Locals_tmp);
} else {
$byte = ord($Locals_img{9});
$byte |= 0x80;
$byte &= 0xF8;
$byte |= (ord($this->BUF[0]{10}) & 0x07);
$Locals_img{9} = chr($byte);
$this->GIF .= ($Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp);
}
} else {
$byte = ord($Locals_img{9});
$byte |= 0x80;
$byte &= 0xF8;
$byte |= (ord($this->BUF[$i]{10}) & 0x07);
$Locals_img{9} = chr($byte);
$this->GIF .= ($Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp);
}
} else {
$this->GIF .= ($Locals_ext . $Locals_img . $Locals_tmp);
}
$this->IMG = 1;
}
function GIFAddFooter() {
$this->GIF .= ";";
}
function GIFBlockCompare($GlobalBlock, $LocalBlock, $Len) {
for ($i = 0; $i < $Len; $i ++) {
if ($GlobalBlock{3 * $i + 0} != $LocalBlock{3 * $i + 0} || $GlobalBlock{3 * $i + 1} != $LocalBlock{3 * $i + 1} || $GlobalBlock{3 * $i + 2} != $LocalBlock{3 * $i + 2}) {
return (0);
}
}
return (1);
}
function GIFWord($int) {
return (chr($int & 0xFF) . chr(($int >> 8) & 0xFF));
}
function GetAnimation() {
return ($this->GIF);
}
}
/*-------------------------------------华丽的分割线----------------------------------*/
/* 调用示例 */
session_start();
$checkCode = '';
$chars = 'abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPRSTUVWXYZ23456789';
for ($i = 0; $i < 4; $i ++) {
$checkCode .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
}
$_SESSION['code'] = strtoupper($checkCode); // 记录session
ImageCode($checkCode, 60);// 显示GIF动画