<?php

/**
 * 图像操作类库.
 +------------------------------------------------------------------------------
 * @category   ORG
 *
 * @author    liu21st <liu21st@gmail.com>
 *
 * @version   $Id$
 */
class Image
{
    //类定义开始

    /**
     * 取得图像信息.
     *
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $image 图像文件名
     +----------------------------------------------------------
     * @return mixed
     */
    public static function getImageInfo($img)
    {
        $imageInfo = getimagesize($img);
        if ($imageInfo !== false) {
            $imageType = strtolower(substr(image_type_to_extension($imageInfo[2]), 1));
            $imageSize = filesize($img);
            $info = array(
                'width'  => $imageInfo[0],
                'height' => $imageInfo[1],
                'type'   => $imageType,
                'size'   => $imageSize,
                'mime'   => $imageInfo['mime'],
            );

            return $info;
        } else {
            return false;
        }
    }

    /**
     * 显示服务器图像文件
     * 支持URL方式.
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $imgFile 图像文件名
     * @param string $text    文字字符串
     * @param string $width   图像宽度
     * @param string $height  图像高度
     */
    public static function showImg($imgFile, $text = '', $width = 80, $height = 30)
    {
        //获取图像文件信息
        $info = self::getImageInfo($imgFile);
        if ($info !== false) {
            $createFun = str_replace('/', 'createfrom', $info['mime']);
            $im = $createFun($imgFile);
            if ($im) {
                $ImageFun = str_replace('/', '', $info['mime']);
                if (!empty($text)) {
                    $tc = imagecolorallocate($im, 0, 0, 0);
                    imagestring($im, 3, 5, 5, $text, $tc);
                }
                if ($info['type'] == 'png' || $info['type'] == 'gif') {
                    imagealphablending($im, false); //取消默认的混色模式
                imagesavealpha($im, true); //设定保存完整的 alpha 通道信息
                }
                header('Content-type: '.$info['mime']);
                $ImageFun($im);
                imagedestroy($im);

                return;
            }
        }
        //获取或者创建图像文件失败则生成空白PNG图片
        $im = imagecreatetruecolor($width, $height);
        $bgc = imagecolorallocate($im, 255, 255, 255);
        $tc = imagecolorallocate($im, 0, 0, 0);
        imagefilledrectangle($im, 0, 0, 150, 30, $bgc);
        imagestring($im, 4, 5, 5, 'NO PIC', $tc);
        self::output($im);
    }

    /**
     * 切割图片.
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $image     原图
     * @param string $cutfile   切割后的图片
     * @param int    $cutWidth
     * @param int    $cutHeight
     */
    public static function cut($image, $filename, $maxWidth = '', $maxHeight = '')
    {

        // 获取原图信息
        $info = self::getImageInfo($image);
        //dump($image);
        if ($info !== false) {
            $srcWidth = $info['width'];
            $srcHeight = $info['height'];
            $pathinfo = pathinfo($image);
            $type = $pathinfo['extension'];
            $type = empty($type) ? $info['type'] : $type;
            $type = strtolower($type);
            $interlace = $interlace ? 1 : 0;
            unset($info);
            // 载入原图 ，兼容2.8下iPhone客户端上传错误，造成的ile后缀文件错误
            $createFun = 'ImageCreateFrom'.(($type == 'jpg' || $type == 'ile') ? 'jpeg' : $type);
            $srcImg = $createFun($image);

            //创建缩略图
            if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
                $thumbImg = imagecreatetruecolor($maxWidth, $maxHeight);
            } else {
                $thumbImg = imagecreate($maxWidth, $maxHeight);
            }

            // 新建PNG缩略图通道透明处理
            if ('png' == $type) {
                imagealphablending($thumbImg, false); //取消默认的混色模式
                imagesavealpha($thumbImg, true); //设定保存完整的 alpha 通道信息
            } elseif ('gif' == $type) {
                // 新建GIF缩略图预处理，保证透明效果不失效
                $background_color = imagecolorallocate($thumbImg, 0, 255, 0);  //  指派一个绿色
                imagecolortransparent($thumbImg, $background_color);  //  设置为透明色，若注释掉该行则输出绿色的图
            }

            // 计算缩放比例
            if (($maxWidth / $maxHeight) >= ($srcWidth / $srcHeight)) {
                //宽不变,截高，从中间截取 y=
                $width = $srcWidth;
                $height = $srcWidth * ($maxHeight / $maxWidth);
                $x = 0;
                $y = ($srcHeight - $height) * 0.5;
            } else {
                //高不变,截宽，从中间截取，x=
                $width = $srcHeight * ($maxWidth / $maxHeight);
                $height = $srcHeight;
                $x = ($srcWidth - $width) * 0.5;
                $y = 0;
            }
            // 复制图片
            if (function_exists('ImageCopyResampled')) {
                imagecopyresampled($thumbImg, $srcImg, 0, 0, $x, $y, $maxWidth, $maxHeight, $width, $height);
            } else {
                imagecopyresized($thumbImg, $srcImg, 0, 0, $x, $y, $maxWidth, $maxHeight, $width, $height);
            }
            imagedestroy($srcImg);

            // 对jpeg图形设置隔行扫描
            if ('jpg' == $type || 'jpeg' == $type) {
                imageinterlace($thumbImg, $interlace);
            }

            // 生成图片
            //$imageFun = 'image'.($type=='jpg'?'jpeg':$type);
            $imageFun = 'imagejpeg';
            $filename = empty($filename) ? substr($image, 0, strrpos($image, '.')).$suffix.'.'.$type : $filename;

            $imageFun($thumbImg, $filename);
            imagedestroy($thumbImg);

            return $filename;
        }

        return false;
    }

    /**

     * 生成缩略图.
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $image     原图
     * @param string $type      图像格式
     * @param string $thumbname 缩略图文件名
     * @param string $maxWidth  宽度
     * @param string $maxHeight 高度
     * @param string $position  缩略图保存目录
     * @param bool   $interlace 启用隔行扫描
     */
    public static function thumb($image, $thumbname, $type = '', $maxWidth = 200, $maxHeight = 'auto', $interlace = true)
    {
        // 获取原图信息
        $info = self::getImageInfo($image);
        if ($info !== false) {
            $srcWidth = $info['width'];
            $srcHeight = $info['height'];
            $type = empty($type) ? $info['type'] : $type;
            $type = strtolower($type);
            $interlace = $interlace ? 1 : 0;
            unset($info);
            if ($maxHeight == 'auto') {
                $scale = $maxWidth / $srcWidth;
            } else {
                $scale = min($maxWidth / $srcWidth, $maxHeight / $srcHeight); // 计算缩放比例
            }
            if ($scale >= 1) {
                // 超过原图大小不再缩略
                $width = $srcWidth;
                $height = $srcHeight;
            } else {
                // 缩略图尺寸
                $width = (int) ($srcWidth * $scale);
                $height = (int) ($srcHeight * $scale);
            }

            // 载入原图
            $createFun = 'ImageCreateFrom'.($type == 'jpg' ? 'jpeg' : $type);
            $srcImg = $createFun($image);

            //创建缩略图
            if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
                $thumbImg = imagecreatetruecolor($width, $height);
            } else {
                $thumbImg = imagecreate($width, $height);
            }

            // 新建PNG缩略图通道透明处理
            if ('png' == $type) {
                imagealphablending($thumbImg, false); //取消默认的混色模式
                imagesavealpha($thumbImg, true); //设定保存完整的 alpha 通道信息
            } elseif ('gif' == $type) {
                // 新建GIF缩略图预处理，保证透明效果不失效
                $background_color = imagecolorallocate($thumbImg, 0, 255, 0);  //  指派一个绿色
                imagecolortransparent($thumbImg, $background_color);  //  设置为透明色，若注释掉该行则输出绿色的图
            }

            // 复制图片
            if (function_exists('ImageCopyResampled')) {
                imagecopyresampled($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height, $srcWidth, $srcHeight);
            } else {
                imagecopyresized($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height, $srcWidth, $srcHeight);
            }
            /*if('gif'==$type || 'png'==$type) {
                //imagealphablending($thumbImg, false);//取消默认的混色模式
                //imagesavealpha($thumbImg,true);//设定保存完整的 alpha 通道信息
                $background_color  =  imagecolorallocate($thumbImg,  0,255,0);  //  指派一个绿色
                imagecolortransparent($thumbImg,$background_color);  //  设置为透明色，若注释掉该行则输出绿色的图
            }*/

            // 对jpeg图形设置隔行扫描
            if ('jpg' == $type || 'jpeg' == $type) {
                imageinterlace($thumbImg, $interlace);
            }

            //$gray=ImageColorAllocate($thumbImg,255,0,0);
            //ImageString($thumbImg,2,5,5,"ThinkPHP",$gray);
            // 生成图片
            $imageFun = 'image'.($type == 'jpg' ? 'jpeg' : $type);
            $imageFun($thumbImg, $thumbname);
            imagedestroy($thumbImg);
            imagedestroy($srcImg);

            return $thumbname;
        }

        return false;
    }

    /**
     * 根据给定的字符串生成图像.
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $string  字符串
     * @param string $size    图像大小 width,height 或者 array(width,height)
     * @param string $font    字体信息 fontface,fontsize 或者 array(fontface,fontsize)
     * @param string $type    图像格式 默认PNG
     * @param int    $disturb 是否干扰 1 点干扰 2 线干扰 3 复合干扰 0 无干扰
     * @param bool   $border  是否加边框 array(color)
     +----------------------------------------------------------
     * @return string
     */
    public static function buildString($string, $rgb = array(), $filename = '', $type = 'png', $disturb = 1, $border = true)
    {
        if (is_string($size)) {
            $size = explode(',', $size);
        }
        $width = $size[0];
        $height = $size[1];
        if (is_string($font)) {
            $font = explode(',', $font);
        }
        $fontface = $font[0];
        $fontsize = $font[1];
        $length = strlen($string);
        $width = ($length * 9 + 10) > $width ? $length * 9 + 10 : $width;
        $height = 22;
        if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
            $im = @imagecreatetruecolor($width, $height);
        } else {
            $im = @imagecreate($width, $height);
        }
        if (empty($rgb)) {
            $color = imagecolorallocate($im, 102, 104, 104);
        } else {
            $color = imagecolorallocate($im, $rgb[0], $rgb[1], $rgb[2]);
        }
        $backColor = imagecolorallocate($im, 255, 255, 255);    //背景色（随机）
        $borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
        $pointColor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));                 //点颜色

        @imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
        @imagerectangle($im, 0, 0, $width - 1, $height - 1, $borderColor);
        @imagestring($im, 5, 5, 3, $string, $color);
        if (!empty($disturb)) {
            // 添加干扰
            if ($disturb = 1 || $disturb = 3) {
                for ($i = 0; $i < 25; $i++) {
                    imagesetpixel($im, mt_rand(0, $width), mt_rand(0, $height), $pointColor);
                }
            } elseif ($disturb = 2 || $disturb = 3) {
                for ($i = 0; $i < 10; $i++) {
                    imagearc($im, mt_rand(-10, $width), mt_rand(-10, $height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $pointColor);
                }
            }
        }
        self::output($im, $type, $filename);
    }

    /**
     * 生成图像验证码
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $length 位数
     * @param string $mode   类型
     * @param string $type   图像格式
     * @param string $width  宽度
     * @param string $height 高度
     +----------------------------------------------------------
     * @return string
     */
    public static function buildImageVerify($length = 4, $mode = 1, $type = 'png', $width = 48, $height = 22, $verifyName = 'verify')
    {
        $randval = StringTool::rand_string($length, $mode);
        //转换成大写字母.
        $_SESSION[$verifyName] = md5(strtoupper($randval));
        $width = ($length * 10 + 10) > $width ? $length * 10 + 10 : $width;
        if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
            $im = @imagecreatetruecolor($width, $height);
        } else {
            $im = @imagecreate($width, $height);
        }
        $r = array(225, 255, 255, 223);
        $g = array(225, 236, 237, 255);
        $b = array(225, 236, 166, 125);
        $key = mt_rand(0, 3);

        $backColor = imagecolorallocate($im, $r[$key], $g[$key], $b[$key]);    //背景色（随机）
        $borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
        $pointColor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));                 //点颜色

        @imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
        @imagerectangle($im, 0, 0, $width - 1, $height - 1, $borderColor);
        $stringColor = imagecolorallocate($im, mt_rand(0, 200), mt_rand(0, 120), mt_rand(0, 120));
        // 干扰
        for ($i = 0; $i < 10; $i++) {
            $fontcolor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
            imagearc($im, mt_rand(-10, $width), mt_rand(-10, $height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $fontcolor);
        }
        for ($i = 0; $i < 25; $i++) {
            $fontcolor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
            imagesetpixel($im, mt_rand(0, $width), mt_rand(0, $height), $pointColor);
        }
        for ($i = 0; $i < $length; $i++) {
            imagestring($im, 5, $i * 10 + 5, mt_rand(1, 8), $randval[$i], $stringColor);
        }
//        @imagestring($im, 5, 5, 3, $randval, $stringColor);
        self::output($im, $type);
    }

    // 中文验证码
    public static function GBVerify($length = 4, $type = 'png', $width = 180, $height = 50, $fontface = 'simhei.ttf', $verifyName = 'verify')
    {
        $code = StringTool::rand_string($length, 4);
        $width = ($length * 45) > $width ? $length * 45 : $width;
        $_SESSION[$verifyName] = md5($code);
        $im = imagecreatetruecolor($width, $height);
        $borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
        $bkcolor = imagecolorallocate($im, 250, 250, 250);
        imagefill($im, 0, 0, $bkcolor);
        @imagerectangle($im, 0, 0, $width - 1, $height - 1, $borderColor);
        // 干扰
        for ($i = 0; $i < 15; $i++) {
            $fontcolor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
            imagearc($im, mt_rand(-10, $width), mt_rand(-10, $height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $fontcolor);
        }
        for ($i = 0; $i < 255; $i++) {
            $fontcolor = imagecolorallocate($im, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));
            imagesetpixel($im, mt_rand(0, $width), mt_rand(0, $height), $fontcolor);
        }
        if (!is_file($fontface)) {
            $fontface = dirname(__FILE__).'/'.$fontface;
        }
        for ($i = 0; $i < $length; $i++) {
            $fontcolor = imagecolorallocate($im, mt_rand(0, 120), mt_rand(0, 120), mt_rand(0, 120)); //这样保证随机出来的颜色较深。
            $codex = StringTool::msubstr($code, $i, 1);
            imagettftext($im, mt_rand(16, 20), mt_rand(-60, 60), 40 * $i + 20, mt_rand(30, 35), $fontcolor, $fontface, $codex);
        }
        self::output($im, $type);
    }

    /**
     * 把图像转换成字符显示.
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $image 要显示的图像
     * @param string $type  图像类型，默认自动获取
     +----------------------------------------------------------
     * @return string
     */
    public static function showASCIIImg($image, $string = '', $type = '')
    {
        $info = self::getImageInfo($image);
        if ($info !== false) {
            $type = empty($type) ? $info['type'] : $type;
            unset($info);
            // 载入原图
            $createFun = 'ImageCreateFrom'.($type == 'jpg' ? 'jpeg' : $type);
            $im = $createFun($image);
            $dx = imagesx($im);
            $dy = imagesy($im);
            $i = 0;
            $out = '<span style="padding:0px;margin:0;line-height:100%;font-size:1px;">';
            set_time_limit(0);
            for ($y = 0; $y < $dy; $y++) {
                for ($x = 0; $x < $dx; $x++) {
                    $col = imagecolorat($im, $x, $y);
                    $rgb = imagecolorsforindex($im, $col);
                    $str = empty($string) ? '*' : $string[$i++];
                    $out .= sprintf('<span style="margin:0px;color:#%02x%02x%02x">'.$str.'</span>', $rgb['red'], $rgb['green'], $rgb['blue']);
                }
                $out .= "<br>\n";
            }
            $out .= '</span>';
            imagedestroy($im);

            return $out;
        }

        return false;
    }

    /**
     * 生成高级图像验证码
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $type   图像格式
     * @param string $width  宽度
     * @param string $height 高度
     +----------------------------------------------------------
     * @return string
     */
    public static function showAdvVerify($type = 'png', $width = 180, $height = 40, $verifyName = 'verifyCode')
    {
        $rand = range('a', 'z');
        shuffle($rand);
        $verifyCode = array_slice($rand, 0, 10);
        $letter = implode(' ', $verifyCode);
        $_SESSION[$verifyName] = $verifyCode;
        $im = imagecreate($width, $height);
        $r = array(225, 255, 255, 223);
        $g = array(225, 236, 237, 255);
        $b = array(225, 236, 166, 125);
        $key = mt_rand(0, 3);
        $backColor = imagecolorallocate($im, $r[$key], $g[$key], $b[$key]);
        $borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
        imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
        imagerectangle($im, 0, 0, $width - 1, $height - 1, $borderColor);
        $numberColor = imagecolorallocate($im, 255, rand(0, 100), rand(0, 100));
        $stringColor = imagecolorallocate($im, rand(0, 100), rand(0, 100), 255);
        // 添加干扰
        /*
        for($i=0;$i<10;$i++){
            $fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
            imagearc($im,mt_rand(-10,$width),mt_rand(-10,$height),mt_rand(30,300),mt_rand(20,200),55,44,$fontcolor);
        }
        for($i=0;$i<255;$i++){
            $fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
            imagesetpixel($im,mt_rand(0,$width),mt_rand(0,$height),$fontcolor);
        }*/
        imagestring($im, 5, 5, 1, '0 1 2 3 4 5 6 7 8 9', $numberColor);
        imagestring($im, 5, 5, 20, $letter, $stringColor);
        self::output($im, $type);
    }

    /**
     * 生成UPC-A条形码
     +----------------------------------------------------------
     * @static
     +----------------------------------------------------------
     * @param string $type 图像格式
     * @param string $type 图像格式
     * @param string $lw   单元宽度
     * @param string $hi   条码高度
     +----------------------------------------------------------
     * @return string
     */
    public static function UPCA($code, $type = 'png', $lw = 2, $hi = 100)
    {
        static $Lencode = array('0001101', '0011001', '0010011', '0111101', '0100011',
                         '0110001', '0101111', '0111011', '0110111', '0001011', );
        static $Rencode = array('1110010', '1100110', '1101100', '1000010', '1011100',
                         '1001110', '1010000', '1000100', '1001000', '1110100', );
        $ends = '101';
        $center = '01010';
        /* UPC-A Must be 11 digits, we compute the checksum. */
        if (strlen($code) != 11) {
            die('UPC-A Must be 11 digits.');
        }
        /* Compute the EAN-13 Checksum digit */
        $ncode = '0'.$code;
        $even = 0;
        $odd = 0;
        for ($x = 0; $x < 12; $x++) {
            if ($x % 2) {
                $odd += $ncode[$x];
            } else {
                $even += $ncode[$x];
            }
        }
        $code .= (10 - (($odd * 3 + $even) % 10)) % 10;
        /* Create the bar encoding using a binary string */
        $bars = $ends;
        $bars .= $Lencode[$code[0]];
        for ($x = 1; $x < 6; $x++) {
            $bars .= $Lencode[$code[$x]];
        }
        $bars .= $center;
        for ($x = 6; $x < 12; $x++) {
            $bars .= $Rencode[$code[$x]];
        }
        $bars .= $ends;
        /* Generate the Barcode Image */
        if ($type != 'gif' && function_exists('imagecreatetruecolor')) {
            $im = imagecreatetruecolor($lw * 95 + 30, $hi + 30);
        } else {
            $im = imagecreate($lw * 95 + 30, $hi + 30);
        }
        $fg = imagecolorallocate($im, 0, 0, 0);
        $bg = imagecolorallocate($im, 255, 255, 255);
        imagefilledrectangle($im, 0, 0, $lw * 95 + 30, $hi + 30, $bg);
        $shift = 10;
        for ($x = 0; $x < strlen($bars); $x++) {
            if (($x < 10) || ($x >= 45 && $x < 50) || ($x >= 85)) {
                $sh = 10;
            } else {
                $sh = 0;
            }
            if ($bars[$x] == '1') {
                $color = $fg;
            } else {
                $color = $bg;
            }
            imagefilledrectangle($im, ($x * $lw) + 15, 5, ($x + 1) * $lw + 14, $hi + 5 + $sh, $color);
        }
        /* Add the Human Readable Label */
        imagestring($im, 4, 5, $hi - 5, $code[0], $fg);
        for ($x = 0; $x < 5; $x++) {
            imagestring($im, 5, $lw * (13 + $x * 6) + 15, $hi + 5, $code[$x + 1], $fg);
            imagestring($im, 5, $lw * (53 + $x * 6) + 15, $hi + 5, $code[$x + 6], $fg);
        }
        imagestring($im, 4, $lw * 95 + 17, $hi - 5, $code[11], $fg);
        /* Output the Header and Content. */
        self::output($im, $type);
    }

    public static function output($im, $type = 'png', $filename = '')
    {
        header('Content-type: image/'.$type);
        $ImageFun = 'image'.$type;
        if (empty($filename)) {
            $ImageFun($im);
        } else {
            $ImageFun($im, $filename);
        }
        imagedestroy($im);
    }
}//类定义结束

if (!function_exists('ImageCreateFrombmp')) {
    function ImageCreateFrombmp($filename)
    {
        $buf = @file_get_contents($filename);

        if (strlen($buf) < 54) {
            return false;
        }

        $file_header = unpack('sbfType/LbfSize/sbfReserved1/sbfReserved2/LbfOffBits', substr($buf, 0, 14));
        if ($file_header['bfType'] != 19778) {
            return false;
        }
        $info_header = unpack('LbiSize/lbiWidth/lbiHeight/sbiPlanes/sbiBitCountLbiCompression/LbiSizeImage/lbiXPelsPerMeter/lbiYPelsPerMeter/LbiClrUsed/LbiClrImportant', substr($buf, 14, 40));
        if ($info_header['biBitCountLbiCompression'] == 2) {
            return false;
        }
        $line_len = round($info_header['biWidth'] * $info_header['biBitCountLbiCompression'] / 8);
        $x = $line_len % 4;
        if ($x > 0) {
            $line_len += 4 - $x;
        }

        $img = imagecreatetruecolor($info_header['biWidth'], $info_header['biHeight']);
        switch ($info_header['biBitCountLbiCompression']) {
        case 4:
            $colorset = unpack('L*', substr($buf, 54, 64));
            for ($y = 0; $y < $info_header['biHeight']; $y++) {
                $colors = array();
                $y_pos = $y * $line_len + $file_header['bfOffBits'];
                for ($x = 0; $x < $info_header['biWidth']; $x++) {
                    if ($x % 2) {
                        $colors[] = $colorset[(ord($buf[$y_pos + ($x + 1) / 2]) & 0xf) + 1];
                    } else {
                        $colors[] = $colorset[((ord($buf[$y_pos + $x / 2 + 1]) >> 4) & 0xf) + 1];
                    }
                }
                imagesetstyle($img, $colors);
                imageline($img, 0, $info_header['biHeight'] - $y - 1, $info_header['biWidth'], $info_header['biHeight'] - $y - 1, IMG_COLOR_STYLED);
            }
            break;
        case 8:
            $colorset = unpack('L*', substr($buf, 54, 1024));
            for ($y = 0; $y < $info_header['biHeight']; $y++) {
                $colors = array();
                $y_pos = $y * $line_len + $file_header['bfOffBits'];
                for ($x = 0; $x < $info_header['biWidth']; $x++) {
                    $colors[] = $colorset[ord($buf[$y_pos + $x]) + 1];
                }
                imagesetstyle($img, $colors);
                imageline($img, 0, $info_header['biHeight'] - $y - 1, $info_header['biWidth'], $info_header['biHeight'] - $y - 1, IMG_COLOR_STYLED);
            }
            break;
        case 16:
            for ($y = 0; $y < $info_header['biHeight']; $y++) {
                $colors = array();
                $y_pos = $y * $line_len + $file_header['bfOffBits'];
                for ($x = 0; $x < $info_header['biWidth']; $x++) {
                    $i = $x * 2;
                    $color = ord($buf[$y_pos + $i]) | (ord($buf[$y_pos + $i + 1]) << 8);
                    $colors[] = imagecolorallocate($img, (($color >> 10) & 0x1f) * 0xff / 0x1f, (($color >> 5) & 0x1f) * 0xff / 0x1f, ($color & 0x1f) * 0xff / 0x1f);
                }
                imagesetstyle($img, $colors);
                imageline($img, 0, $info_header['biHeight'] - $y - 1, $info_header['biWidth'], $info_header['biHeight'] - $y - 1, IMG_COLOR_STYLED);
            }
            break;
        case 24:
            for ($y = 0; $y < $info_header['biHeight']; $y++) {
                $colors = array();
                $y_pos = $y * $line_len + $file_header['bfOffBits'];
                for ($x = 0; $x < $info_header['biWidth']; $x++) {
                    $i = $x * 3;
                    $colors[] = imagecolorallocate($img, ord($buf[$y_pos + $i + 2]), ord($buf[$y_pos + $i + 1]), ord($buf[$y_pos + $i]));
                }
                imagesetstyle($img, $colors);
                imageline($img, 0, $info_header['biHeight'] - $y - 1, $info_header['biWidth'], $info_header['biHeight'] - $y - 1, IMG_COLOR_STYLED);
            }
            break;
        default:
            return false;
            break;
    }

        return $img;
    }
    function imagebmp(&$im, $filename = '', $bit = 8, $compression = 0)
    {
        if (!in_array($bit, array(1, 4, 8, 16, 24, 32))) {
            $bit = 8;
        } elseif ($bit == 32) {
            // todo:32 bit

        $bit = 24;
        }

        $bits = pow(2, $bit);

    // 调整调色板
    imagetruecolortopalette($im, true, $bits);
        $width = imagesx($im);
        $height = imagesy($im);
        $colors_num = imagecolorstotal($im);

        if ($bit <= 8) {
            // 颜色索引
        $rgb_quad = '';
            for ($i = 0; $i < $colors_num; $i++) {
                $colors = imagecolorsforindex($im, $i);
                $rgb_quad .= chr($colors['blue']).chr($colors['green']).chr($colors['red'])."\0";
            }

        // 位图数据
        $bmp_data = '';

        // 非压缩
        if ($compression == 0 || $bit < 8) {
            if (!in_array($bit, array(1, 4, 8))) {
                $bit = 8;
            }

            $compression = 0;

        // 每行字节数必须为4的倍数，补齐。

            $extra = '';
            $padding = 4 - ceil($width / (8 / $bit)) % 4;
            if ($padding % 4 != 0) {
                $extra = str_repeat("\0", $padding);
            }

            for ($j = $height - 1; $j >= 0; $j--) {
                $i = 0;
                while ($i < $width) {
                    $bin = 0;
                    $limit = $width - $i < 8 / $bit ? (8 / $bit - $width + $i) * $bit : 0;

                    for ($k = 8 - $bit; $k >= $limit; $k -= $bit) {
                        $index = imagecolorat($im, $i, $j);
                        $bin |= $index << $k;
                        $i++;
                    }

                    $bmp_data .= chr($bin);
                }

                $bmp_data .= $extra;
            }
        }
                // RLE8 压缩
                elseif ($compression == 1 && $bit == 8) {
                    for ($j = $height - 1; $j >= 0; $j--) {
                        $last_index = "\0";
                        $same_num = 0;
                        for ($i = 0; $i <= $width; $i++) {
                            $index = imagecolorat($im, $i, $j);
                            if ($index !== $last_index || $same_num > 255) {
                                if ($same_num != 0) {
                                    $bmp_data .= chr($same_num).chr($last_index);
                                }

                                $last_index = $index;
                                $same_num = 1;
                            } else {
                                $same_num++;
                            }
                        }

                        $bmp_data .= "\0\0";
                    }

                    $bmp_data .= "\0\1";
                }

            $size_quad = strlen($rgb_quad);
            $size_data = strlen($bmp_data);
        } else {
            // 每行字节数必须为4的倍数，补齐。
                            $extra = '';
            $padding = 4 - ($width * ($bit / 8)) % 4;
            if ($padding % 4 != 0) {
                $extra = str_repeat("\0", $padding);
            }

                                    // 位图数据
                                    $bmp_data = '';

            for ($j = $height - 1; $j >= 0; $j--) {
                for ($i = 0; $i < $width; $i++) {
                    $index = imagecolorat($im, $i, $j);
                    $colors = imagecolorsforindex($im, $index);

                    if ($bit == 16) {
                        $bin = 0 << $bit;

                        $bin |= ($colors['red'] >> 3) << 10;
                        $bin |= ($colors['green'] >> 3) << 5;
                        $bin |= $colors['blue'] >> 3;

                        $bmp_data .= pack('v', $bin);
                    } else {
                        $bmp_data .= pack('c*', $colors['blue'], $colors['green'], $colors['red']);
                    }

                // todo: 32bit;
                }

                $bmp_data .= $extra;
            }

            $size_quad = 0;
            $size_data = strlen($bmp_data);
            $colors_num = 0;
        }

                // 位图文件头
                $file_header = 'BM'.pack('V3', 54 + $size_quad + $size_data, 0, 54 + $size_quad);

                // 位图信息头
                $info_header = pack('V3v2V*', 0x28, $width, $height, 1, $bit, $compression, $size_data, 0, 0, $colors_num, 0);
                // 写入文件
                if ($filename != '') {
                    $fp = fopen($filename, 'wb');

                    fwrite($fp, $file_header);
                    fwrite($fp, $info_header);
                    fwrite($fp, $rgb_quad);
                    fwrite($fp, $bmp_data);
                    fclose($fp);

                    return 1;
                }

                // 浏览器输出
                header('Content-Type: image/bmp');
        echo $file_header.$info_header;
        echo $rgb_quad;
        echo $bmp_data;

        return 1;
    }
}
