thinkphp image类添加png图片水印不投明问题
1、添加水印可以参照手册，直接引入image类，使用water方法即可
2、在导入类后，我们发现如果使用png图片作为水印背景，会出现添加水印时原来应该是透明的部分变成了黑色
3、在网上找了一番之后，对image类的water方法做下述修改
大约在82行
//生成混合图像
// imagecopymerge($sImage, $wImage, $posX, $posY, 0, 0, $wInfo['width'], $wInfo['height'], $alpha);
imagecopy($sImage, $wImage, $posX, $posY, 0, 0, $wInfo['width'], $wInfo['height']);对，你没有看错，把他原来的注释掉，改成下面的就好了。
下面放上整个image类的代码，便于以后查看下载
<?php // +---------------------------------------------------------------------- // | ThinkPHP [ WE CAN DO IT JUST THINK IT ] // +---------------------------------------------------------------------- // | Copyright (c) 2009 http://thinkphp.cn All rights reserved. // +---------------------------------------------------------------------- // | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 ) // +---------------------------------------------------------------------- // | Author: liu21st <[email protected]> // +---------------------------------------------------------------------- /** * 图像操作类库 * @category ORG * @package ORG * @subpackage Util * @author liu21st <[email protected]> */ class Image { /** * 取得图像信息 * @static * @access public * @param string $image 图像文件名 * @return mixed */ static function getImageInfo($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; } } /** * 为图片添加水印 * @static public * @param string $source 原文件名 * @param string $water 水印图片 * @param string $$savename 添加水印后的图片名 * @param string $alpha 水印的透明度 * @return void */ static public function water($source, $water, $savename=null, $alpha=80) { //检查文件是否存在 if (!file_exists($source) || !file_exists($water)) return false; //图片信息 $sInfo = self::getImageInfo($source); $wInfo = self::getImageInfo($water); //如果图片小于水印图片，不生成图片 if ($sInfo["width"] < $wInfo["width"] || $sInfo['height'] < $wInfo['height']) return false; //建立图像 $sCreateFun = "imagecreatefrom" . $sInfo['type']; $sImage = $sCreateFun($source); $wCreateFun = "imagecreatefrom" . $wInfo['type']; $wImage = $wCreateFun($water); //设定图像的混色模式 imagealphablending($wImage, true); //图像位置,默认为右下角右对齐 $posY = $sInfo["height"] - $wInfo["height"]; $posX = $sInfo["width"] - $wInfo["width"]; //生成混合图像 // imagecopymerge($sImage, $wImage, $posX, $posY, 0, 0, $wInfo['width'], $wInfo['height'], $alpha); imagecopy($sImage, $wImage, $posX, $posY, 0, 0, $wInfo['width'], $wInfo['height']); //输出图像 $ImageFun = 'Image' . $sInfo['type']; //如果没有给出保存文件名，默认为原图像名 if (!$savename) { $savename = $source; @unlink($source); } //保存图像 $ImageFun($sImage, $savename); imagedestroy($sImage); } function showImg($imgFile, $text='', $x='10', $y='10', $alpha='50') { //获取图像文件信息 //2007/6/26 增加图片水印输出，$text为图片的完整路径即可 $info = Image::getImageInfo($imgFile); if ($info !== false) { $createFun = str_replace('/', 'createfrom', $info['mime']); $im = $createFun($imgFile); if ($im) { $ImageFun = str_replace('/', '', $info['mime']); //水印开始 if (!empty($text)) { $tc = imagecolorallocate($im, 0, 0, 0); if (is_file($text) && file_exists($text)) {//判断$text是否是图片路径 // 取得水印信息 $textInfo = Image::getImageInfo($text); $createFun2 = str_replace('/', 'createfrom', $textInfo['mime']); $waterMark = $createFun2($text); //$waterMark=imagecolorallocatealpha($text,255,255,0,50); $imgW = $info["width"]; $imgH = $info["width"] * $textInfo["height"] / $textInfo["width"]; //$y = ($info["height"]-$textInfo["height"])/2; //设置水印的显示位置和透明度支持各种图片格式 imagecopymerge($im, $waterMark, $x, $y, 0, 0, $textInfo['width'], $textInfo['height'], $alpha); } else { imagestring($im, 80, $x, $y, $text, $tc); } //ImageDestroy($tc); } //水印结束 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; } //保存图像 $ImageFun($sImage, $savename); imagedestroy($sImage); //获取或者创建图像文件失败则生成空白PNG图片 $im = imagecreatetruecolor(80, 30); $bgc = imagecolorallocate($im, 255, 255, 255); $tc = imagecolorallocate($im, 0, 0, 0); imagefilledrectangle($im, 0, 0, 150, 30, $bgc); imagestring($im, 4, 5, 5, "no pic", $tc); Image::output($im); return; } } /** * 生成缩略图 * @static * @access public * @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 boolean $interlace 启用隔行扫描 * @return void */ static function thumb($image, $thumbname, $type='', $maxWidth=200, $maxHeight=50, $interlace=true) { // 获取原图信息 $info = Image::getImageInfo($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); $scale = min($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' : $type); if(!function_exists($createFun)) { return false; } $srcImg = $createFun($image); //创建缩略图 if ($type != 'gif' && function_exists('imagecreatetruecolor')) $thumbImg = imagecreatetruecolor($width, $height); else $thumbImg = imagecreate($width, $height); //png和gif的透明处理 by luofei614 if('png'==$type){ imagealphablending($thumbImg, false);//取消默认的混色模式（为解决阴影为绿色的问题） imagesavealpha($thumbImg,true);//设定保存完整的 alpha 通道信息（为解决阴影为绿色的问题） }elseif('gif'==$type){ $trnprt_indx = imagecolortransparent($srcImg); if ($trnprt_indx >= 0) { //its transparent $trnprt_color = imagecolorsforindex($srcImg , $trnprt_indx); $trnprt_indx = imagecolorallocate($thumbImg, $trnprt_color['red'], $trnprt_color['green'], $trnprt_color['blue']); imagefill($thumbImg, 0, 0, $trnprt_indx); imagecolortransparent($thumbImg, $trnprt_indx); } } // 复制图片 if (function_exists("ImageCopyResampled")) imagecopyresampled($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height, $srcWidth, $srcHeight); else imagecopyresized($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height, $srcWidth, $srcHeight); // 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); $imageFun($thumbImg, $thumbname); imagedestroy($thumbImg); imagedestroy($srcImg); return $thumbname; } return false; } /** * 根据给定的字符串生成图像 * @static * @access public * @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 integer $disturb 是否干扰 1 点干扰 2 线干扰 3 复合干扰 0 无干扰 * @param bool $border 是否加边框 array(color) * @return string */ static function buildString($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, $pointColor); } } } Image::output($im, $type, $filename); } /** * 生成图像验证码 * @static * @access public * @param string $length 位数 * @param string $mode 类型 * @param string $type 图像格式 * @param string $width 宽度 * @param string $height 高度 * @return string */ static function buildImageVerify($length=4, $mode=1, $type='png', $width=48, $height=22, $verifyName='verify') { import('ORG.Util.String'); $randval = String::randString($length, $mode); session($verifyName, md5($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 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; $i++) { imagearc($im, mt_rand(-10, $width), mt_rand(-10, $height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $stringColor); } for ($i = 0; $i < 25; $i++) { imagesetpixel($im, mt_rand(0, $width), mt_rand(0, $height), $stringColor); } for ($i = 0; $i < $length; $i++) { imagestring($im, 5, $i * 10 + 5, mt_rand(1, 8), $randval{$i}, $stringColor); } Image::output($im, $type); } // 中文验证码 static function GBVerify($length=4, $type='png', $width=180, $height=50, $fontface='simhei.ttf', $verifyName='verify') { import('ORG.Util.String'); $code = String::randString($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。 $codex = String::msubstr($code, $i, 1); imagettftext($im, mt_rand(16, 20), mt_rand(-60, 60), 40 * $i + 20, mt_rand(30, 35), $fontcolor, $fontface, $codex); } Image::output($im, $type); } /** * 把图像转换成字符显示 * @static * @access public * @param string $image 要显示的图像 * @param string $type 图像类型，默认自动获取 * @return string */ static function showASCIIImg($image, $string='', $type='') { $info = Image::getImageInfo($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 $hi 条码高度 * @return string */ static function UPCA($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], $fg); /* Output the Header and Content. */ Image::output($im, $type); } static function output($im, $type='png', $filename='') { header("Content-type: image/" . $type); $ImageFun = 'image' . $type; if (empty($filename)) { $ImageFun($im); } else { $ImageFun($im, $filename); } imagedestroy($im); } }