本文实例讲述了php图像处理类。分享给大家供大家参考。具体如下:
<?php /** * Image 类 */ class Image { /** * @var string $fileName 文件名 * @access private */ private $fileName = ''; /** * @var gd resource $imageResource 原图像 * @access private */ private $imageResource = NULL; /** * @var int $imageWidth 原图像宽 * @access private */ private $imageWidth = NULL; /** * @var int $imageHeight 原图像高 * @access private */ private $imageHeight = NULL; /** * @var int $imageType 原图像类型 * @access private */ private $imageType = NULL; /** * @var int $imageWidth 原图像宽 * @access private */ public $width = NULL; /** * @var int $imageHeight 原图像高 * @access private */ public $height = NULL; /** * @var int $imageType 原图像类型 * @access private */ public $type = NULL; /** * @var int $newResource 新图像 * @access private */ private $newResource = NULL; /** * @var int $newResType 新图像类型 * @access private */ private $newResType = NULL; /** * 构造函数 * @param string $fileName 文件名 */ public function __construct($fileName = NULL) { $this->fileName = $fileName; if ($this->fileName) { $this->getSrcImageInfo(); } } /** * 取源图像信息 * @access private * @return void */ private function getSrcImageInfo() { $info = $this->getImageInfo(); $this->imageWidth = $info[0]; $this->imageHeight = $info[1]; $this->imageType = $info[2]; $this->width = $info[0]; $this->height = $info[1]; $this->type = $info[2]; } /** * 取图像信息 * @param string $fileName 文件名 * @access private * @return array */ private function getImageInfo($fileName = NULL) { if ($fileName==NULL) { $fileName = $this->fileName; } $info = getimagesize($fileName); return $info; } /** * 创建源图像GD 资源 * @access private * @return void */ private function createSrcImage () { $this->imageResource = $this->createImageFromFile(); } /** * 跟据文件创建图像GD 资源 * @param string $fileName 文件名 * @return gd resource */ public function createImageFromFile($fileName = NULL) { if (!$fileName) { $fileName = $this->fileName; $imgType = $this->imageType; } if (!is_readable($fileName) || !file_exists($fileName)) { throw new Exception('Unable to open file "' . $fileName . '"'); } if (!$imgType) { $imageInfo = $this->getImageInfo($fileName); $imgType = $imageInfo[2]; } switch ($imgType) { case IMAGETYPE_GIF: $tempResource = imagecreatefromgif($fileName); break; case IMAGETYPE_JPEG: $tempResource = imagecreatefromjpeg($fileName); break; case IMAGETYPE_PNG: $tempResource = imagecreatefrompng($fileName); break; case IMAGETYPE_WBMP: $tempResource = imagecreatefromwbmp($fileName); break; case IMAGETYPE_XBM: $tempResource = imagecreatefromxbm($fileName); break; default: throw new Exception('Unsupport image type'); } return $tempResource; } /** * 改变图像大小 * @param int $width 宽 * @param int $height 高 * @param string $flag 一般而言,允许截图则用4,不允许截图则用1; 假设要求一个为4:3比例的图像,则:4=如果太长则自动刪除一部分 0=长宽转换成参数指定的 1=按比例缩放,自动判断太长还是太宽,长宽约束在参数指定内 2=以宽为约束缩放 3=以高为约束缩放 * @param string $bgcolor 如果不为null,则用这个参数指定的颜色作为背景色,并且图像扩充到指定高宽,该参数应该是一个数组; * @return string */ public function resizeImage($width, $height, $flag=1, $bgcolor=null) { $widthRatio = $width/$this->imageWidth; $heightRatio = $height/$this->imageHeight; switch ($flag) { case 1: if ($this->imageHeight < $height && $this->imageWidth < $width) { $endWidth = $this->imageWidth; $endHeight = $this->imageHeight; //return; } elseif (($this->imageHeight * $widthRatio)>$height) { $endWidth = ceil($this->imageWidth * $heightRatio); $endHeight = $height; } else { $endWidth = $width; $endHeight = ceil($this->imageHeight * $widthRatio); } break; case 2: $endWidth = $width; $endHeight = ceil($this->imageHeight * $widthRatio); break; case 3: $endWidth = ceil($this->imageWidth * $heightRatio); $endHeight = $height; break; case 4: $endWidth2 = $width; $endHeight2 = $height; if ($this->imageHeight < $height && $this->imageWidth < $width) { $endWidth = $this->imageWidth; $endHeight = $this->imageHeight; //return; } elseif (($this->imageHeight * $widthRatio)<$height) { $endWidth = ceil($this->imageWidth * $heightRatio); $endHeight = $height; } else { $endWidth = $width; $endHeight = ceil($this->imageHeight * $widthRatio); } break; default: $endWidth = $width; $endHeight = $height; break; } if ($this->imageResource==NULL) { $this->createSrcImage(); } if($bgcolor){ $this->newResource = imagecreatetruecolor($width,$height); $bg=ImageColorAllocate($this->newResource,$bgcolor[0],$bgcolor[1],$bgcolor[2]); ImageFilledRectangle($this->newResource,0,0,$width,$height,$bg); $tox=ceil(($width-$endWidth)/2); $toy=ceil(($height-$endHeight)/2); if($tox<0) $tox=0; if($toy<0) $toy=0; }else if ($flag==4) { $this->newResource = imagecreatetruecolor($endWidth2,$endHeight2); }else { $this->newResource = imagecreatetruecolor($endWidth,$endHeight); } $this->newResType = $this->imageType; imagecopyresampled($this->newResource, $this->imageResource, $tox, $toy, 0, 0, $endWidth, $endHeight,$this->imageWidth,$this->imageHeight); } /** * 给图像加水印 * @param string $waterContent 水印内容可以是图像文件名,也可以是文字 * @param int $pos 位置0-9可以是数组 * @param int $textFont 字体大字,当水印内容是文字时有效 * @param string $textColor 文字颜色,当水印内容是文字时有效 * @return string */ public function waterMark($waterContent, $pos = 0, $textFont=5, $textColor="#ffffff") { $isWaterImage = file_exists($waterContent); if ($isWaterImage) { $waterImgRes = $this->createImageFromFile($waterContent); $waterImgInfo = $this->getImageInfo($waterContent); $waterWidth = $waterImgInfo[0]; $waterHeight = $waterImgInfo[1]; } else { $waterText = $waterContent; //$temp = @imagettfbbox(ceil($textFont*2.5),0,"./cour.ttf",$waterContent); if ($temp) { $waterWidth = $temp[2]-$temp[6]; $waterHeight = $temp[3]-$temp[7]; } else { $waterWidth = 100; $waterHeight = 12; } } if ($this->imageResource==NULL) { $this->createSrcImage(); } switch($pos) { case 0://随机 $posX = rand(0,($this->imageWidth - $waterWidth)); $posY = rand(0,($this->imageHeight - $waterHeight)); break; case 1://1为顶端居左 $posX = 0; $posY = 0; break; case 2://2为顶端居中 $posX = ($this->imageWidth - $waterWidth) / 2; $posY = 0; break; case 3://3为顶端居右 $posX = $this->imageWidth - $waterWidth; $posY = 0; break; case 4://4为中部居左 $posX = 0; $posY = ($this->imageHeight - $waterHeight) / 2; break; case 5://5为中部居中 $posX = ($this->imageWidth - $waterWidth) / 2; $posY = ($this->imageHeight - $waterHeight) / 2; break; case 6://6为中部居右 $posX = $this->imageWidth - $waterWidth; $posY = ($this->imageHeight - $waterHeight) / 2; break; case 7://7为底端居左 $posX = 0; $posY = $this->imageHeight - $waterHeight; break; case 8://8为底端居中 $posX = ($this->imageWidth - $waterWidth) / 2; $posY = $this->imageHeight - $waterHeight; break; case 9://9为底端居右 $posX = $this->imageWidth - $waterWidth-20; $posY = $this->imageHeight - $waterHeight-10; break; default://随机 $posX = rand(0,($this->imageWidth - $waterWidth)); $posY = rand(0,($this->imageHeight - $waterHeight)); break; } imagealphablending($this->imageResource, true); if($isWaterImage) { imagecopy($this->imageResource, $waterImgRes, $posX, $posY, 0, 0, $waterWidth,$waterHeight); } else { $R = hexdec(substr($textColor,1,2)); $G = hexdec(substr($textColor,3,2)); $B = hexdec(substr($textColor,5)); $textColor = imagecolorallocate($this->imageResource, $R, $G, $B); imagestring ($this->imageResource, $textFont, $posX, $posY, $waterText, $textColor); } $this->newResource = $this->imageResource; $this->newResType = $this->imageType; } /** * 生成验证码图片 * @param int $width 宽 * @param string $height 高 * @param int $length 长度 * @param int $validType 0=数字,1=字母,2=数字加字母 * @param string $textColor 文字颜色 * @param string $backgroundColor 背景颜色 * @return void */ public function imageValidate($width, $height, $length = 4, $validType = 1, $textColor = '#000000', $backgroundColor = '#ffffff') { if ($validType==1) { $validString = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; $validLength = 52; } elseif ($validType==2) { $validString = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; $validLength = 62; } else { $validString = '123456789'; $validLength = 9; } srand((int)time()); $valid = ''; for ($i=0; $i<$length; $i++) { $valid .= $validString{rand(0, $validLength-1)}; } $this->newResource = imagecreate($width,$height); $bgR = hexdec(substr($backgroundColor,1,2)); $bgG = hexdec(substr($backgroundColor,3,2)); $bgB = hexdec(substr($backgroundColor,5,2)); $backgroundColor = imagecolorallocate($this->newResource, $bgR, $bgG, $bgB); $tR = hexdec(substr($textColor,1,2)); $tG = hexdec(substr($textColor,3,2)); $tB = hexdec(substr($textColor,5,2)); $textColor = imagecolorallocate($this->newResource, $tR, $tG, $tB); for ($i=0;$i<strlen($valid);$i++){ imagestring($this->newResource,5,$i*$width/$length+3,2, $valid[$i],$textColor); } $this->newResType = IMAGETYPE_JPEG; return $valid; } /** * 显示输出图像 * @return void */ public function display($fileName='', $quality=100) { $imgType = $this->newResType; $imageSrc = $this->newResource; switch ($imgType) { case IMAGETYPE_GIF: if ($fileName=='') { header('Content-type: image/gif'); } imagegif($imageSrc, $fileName, $quality); break; case IMAGETYPE_JPEG: if ($fileName=='') { header('Content-type: image/jpeg'); } imagejpeg($imageSrc, $fileName, $quality); break; case IMAGETYPE_PNG: if ($fileName=='') { header('Content-type: image/png'); imagepng($imageSrc); } else { imagepng($imageSrc, $fileName); } break; case IMAGETYPE_WBMP: if ($fileName=='') { header('Content-type: image/wbmp'); } imagewbmp($imageSrc, $fileName, $quality); break; case IMAGETYPE_XBM: if ($fileName=='') { header('Content-type: image/xbm'); } imagexbm($imageSrc, $fileName, $quality); break; default: throw new Exception('Unsupport image type'); } imagedestroy($imageSrc); } /** * 保存图像 * @param int $fileNameType 文件名类型 0使用原文件名,1使用指定的文件名,2在原文件名加上后缀,3产生随机文件名 * @param string $folder 文件夹路径 为空为与原文件相同 * @param string $param 参数$fileNameType为1时为文件名2时为后缀 * @return void */ public function save($fileNameType = 0, $folder = NULL, $param = '_miniature') { if ($folder==NULL) { $folder = dirname($this->fileName).DIRECTORY_SEPARATOR; } $fileExtName = FileSystem::fileExt($this->fileName, true); $fileBesicName = FileSystem::getBasicName($this->fileName, false); switch ($fileNameType) { case 1: $newFileName = $folder.$param; break; case 2: $newFileName = $folder.$fileBesicName.$param.$fileExtName; break; case 3: $tmp = date('YmdHis'); $fileBesicName = $tmp; $i = 0; while (file_exists($folder.$fileBesicName.$fileExtName)) { $fileBesicName = $tmp.$i; $i++; } $newFileName = $folder.$fileBesicName.$fileExtName; break; default: $newFileName = $this->fileName; break; } $this->display($newFileName); return $newFileName; } } ?>
希望本文所述对大家的php程序设计有所帮助。

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