A PHP image processing class that can scale images and add watermarks to images. Friends in need can refer to it.
The code is as follows: <?php class Image { private $path; //构造方法用来对图片所在位置进行初使化 function __construct($path="./"){ $this->path=rtrim($path, "/")."/"; } /* 对图片进行缩放 * * 参数$name: 是需要处理的图片名称 * 参数$width:是缩放后的宽度 * 参数$height:是缩放后的高度 * 参数$qz: 是新图片的名称前缀 * 返回值:就是缩放后的图片名称,失败则返回false * */ function thumb($name, $width, $height, $qz="th_"){ //获取图片信息 $imgInfo=$this->getInfo($name); //图片的宽度,高度,类型 //获取图片资源, 各种类型的图片都可以创建资源 jpg, gif, png $srcImg=$this->getImg($name, $imgInfo); //获取计算图片等比例之后的大小, $size["width"], $size["height"] $size=$this->getNewSize($name, $width, $height, $imgInfo); //获取新的图片资源, 处理一下gif透明背景 $newImg=$this->kidOfImage($srcImg, $size, $imgInfo); //另存为一个新的图片,返回新的缩放后的图片名称 return $this->createNewImage($newImg, $qz.$name, $imgInfo); } private function createNewImage($newImg, $newName, $imgInfo){ switch($imgInfo["type"]){ case 1://gif $result=imageGif($newImg, $this->path.$newName); break; case 2://jpg $result=imageJPEG($newImg, $this->path.$newName); break; case 3://png $return=imagepng($newImg, $this->path.$newName); break; } imagedestroy($newImg); return $newName; } private function kidOfImage($srcImg, $size, $imgInfo){ $newImg=imagecreatetruecolor($size["width"], $size["height"]); $otsc=imagecolortransparent($srcImg); if($otsc >=0 && $otsc <= imagecolorstotal($srcImg)){ $tran=imagecolorsforindex($srcImg, $otsc); $newt=imagecolorallocate($newImg, $tran["red"], $tran["green"], $tran["blue"]); imagefill($newImg, 0, 0, $newt); imagecolortransparent($newImg, $newt); } imagecopyresized($newImg, $srcImg, 0, 0, 0, 0, $size["width"], $size["height"], $imgInfo["width"], $imgInfo["height"]); imagedestroy($srcImg); return $newImg; } private function getNewSize($name, $width, $height, $imgInfo){ $size["width"]=$imgInfo["width"]; $size["height"]=$imgInfo["height"]; //缩放的宽度如果比原图小才重新设置宽度 if($width < $imgInfo["width"]){ $size["width"]=$width; } //缩放的高度如果比原图小才重新设置高度 if($height < $imgInfo["height"]){ $size["height"]=$height; } //图片等比例缩放的算法 if($imgInfo["width"]*$size["width"] > $imgInfo["height"] * $size["height"]){ $size["height"]=round($imgInfo["height"]*$size["width"]/$imgInfo["width"]); }else{ $size["width"]=round($imgInfo["width"]*$size["height"]/$imgInfo["height"]); } return $size; } private function getInfo($name){ $data=getImageSize($this->path.$name); $imageInfo["width"]=$data[0]; $imageInfo["height"]=$data[1]; $imageInfo["type"]=$data[2]; return $imageInfo; } private function getImg($name, $imgInfo){ $srcPic=$this->path.$name; switch($imgInfo["type"]){ case 1: //gif $img=imagecreatefromgif($srcPic); break; case 2: //jpg $img=imageCreatefromjpeg($srcPic); break; case 3: //png $img=imageCreatefrompng($srcPic); break; default: return false; } return $img; } /* 功能:为图片加水印图片 * 参数$groundName: 背景图片,即需要加水印的图片 * 参数$waterName: 水钱图片 * 参数#aterPost:水印位置, 10种状态, * 0为随机位置 * * 1. 为顶端居左 2. 为顶端居中 3 为顶端居右 * 4 为中部居左 5. 为中部居中 6 为中部居右 * 7 . 为底端居左 8. 为底端居中, 9. 为底端居右 * * 参数$qz : 是加水印后的图片名称前缀 * 返回值:就是处理后图片的名称 * */ function waterMark($groundName, $waterName, $waterPos=0, $qz="wa_"){ if(file_exists($this->path.$groundName) && file_exists($this->path.$waterName)){ $groundInfo=$this->getInfo($groundName); $waterInfo=$this->getInfo($waterName); //水印的位置 if(!$pos=$this->position($groundInfo, $waterInfo, $waterPos)){ echo "水印不应该比背景图片小!"; return; } $groundImg=$this->getImg($groundName, $groundInfo); $waterImg=$this->getImg($waterName, $waterInfo); $groundImg=$this->copyImage($groundImg, $waterImg, $pos, $waterInfo); return $this->createNewImage($groundImg, $qz.$groundName, $groundInfo); }else{ echo "图片或水印图片不存在"; return false; } } private function copyImage($groundImg, $waterImg, $pos, $waterInfo){ imagecopy($groundImg, $waterImg, $pos["posX"], $pos["posY"], 0, 0, $waterInfo["width"], $waterInfo["height"]); imagedestroy($waterImg); return $groundImg; } private function position($groundInfo, $waterInfo, $waterPos){ //需要背景比水印图片大 if(($groundInfo["width"]< $waterInfo["width"]) ||($groundInfo["height"] < $waterInfo["height"])){ return false; } switch($waterPos){ case 1: $posX=0; $posY=0; break; case 2: $posX=($groundInfo["width"]-$waterInfo["width"])/2; $posY=0; break; case 3: $posX=$groundInfo["width"]-$waterInfo["width"]; $posY=0; break; case 4: $posX=0; $posY=($groundInfo["height"]-$waterInfo["height"]) /2; break; case 5: $posX=($groundInfo["width"]-$waterInfo["width"])/2; $posY=($groundInfo["height"]-$waterInfo["height"]) /2; break; case 6: $posX=$groundInfo["width"]-$waterInfo["width"]; $posY=($groundInfo["height"]-$waterInfo["height"]) /2; break; case 7: $posX=0; $posY=$groundInfo["height"]-$waterInfo["height"]; break; case 8: $posX=($groundInfo["width"]-$waterInfo["width"])/2; $posY=$groundInfo["height"]-$waterInfo["height"]; break; case 9: $posX=$groundInfo["width"]-$waterInfo["width"]; $posY=$groundInfo["height"]-$waterInfo["height"]; break; case 0: default: $posX=rand(0, ($groundInfo["width"]-$waterInfo["width"])); $posY=rand(0, ($groundInfo["height"]-$waterInfo["height"])); break; } return array("posX"=>$posX, "posY"=>$posY); } } |

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