本文实例为大家分享了php水印和缩略图制作代码，使用面向对象的方法来实现常见图片格式jpg，png，gif的水印和缩略图的制作，供大家参考，具体内容如下

<?php header('Content-Type:text/html;charset=utf-8'); /* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ //给图片添加水印 Class Water{ //开启水印 private $watermark_on = '1'; public $water_img; //水印位置 public $pos = 1; //压缩比 public $pct = 80; //透明度 public $quality = 80; public $text = '乐趣网zlblog.sinaapp.com'; public $size = 12; public $color = '#000000'; public $font = 'font.ttf'; //thumb的制作 //默认缩略图功能开启 private $thumb_on = 1; //生成缩略图的方式 public $thumb_type = 1; //生成缩略图的宽度 public $thumb_width; //生成缩略图的高度 public $thumb_height; //生成缩略图的后缀名 public $thumb_fix = '_dq'; //缩略图函数处理 public function thumb( $img,$outfile='',$t_type='',$t_w='',$t_h='' ){ //验证图片是否符合要求 if(!$this->check($img) || !$this->thumb_on) return FALSE; //定义缩略图的初始值 $t_type = $t_type ? $t_type : $this->thumb_type; $t_w = $t_w ? $t_w : $this->thumb_width; $t_h = $t_h ? $t_h : $this->thumb_height; //获取到原图的信息 $img_info = getimagesize($img); $img_w = $img_info[0]; $img_h = $img_info[1]; //取得图像类型的文件后缀 $img_type = image_type_to_extension($img_info[2]); //获取到相关尺寸 $thumb_size = $this->thumb_size($img_w,$img_h,$t_w,$t_h,$t_type); //确定原始图像类型 //利用自定义函数来实现图片类型的确定 $func = "imagecreatefrom".substr($img_type, 1); $res_img = $func($img); //缩略图资源 编辑图片资源moon if( $img_type == '.gif' || $img_type == '.png' ){ $res_thumb = imagecreate($thumb_size[0], $thumb_size[1]); $color = imagecolorallocate($res_thumb, 255, 0, 0); }else{ $res_thumb = imagecreatetruecolor($thumb_size[0], $thumb_size[1]); } //制作缩略图 if(function_exists( "imagecopyresampled" ) ){ imagecopyresampled($res_thumb, $res_img, 0, 0, 0, 0, $thumb_size[0],$thumb_size[1],$thumb_size[2],$thumb_size[3]); }else{ imagecopyresized($res_thumb, $res_img, 0, 0, 0, 0, $thumb_size[0],$thumb_size[1],$thumb_size[2],$thumb_size[3]); } //处理透明色 if( $img_type =='.gif' || $img_type == '.png' ){ imagecolortransparent($res_thumb,$color); } //配置输出文件名 $outfile = $outfile ? $outfile : $outfile.substr($img,0,strripos($img,'.')).$this->thumb_fix.$img_type; //文件的保存输出 $func = "image".substr($img_type, 1); $func($res_thumb,$outfile); if(isset($res_thumb)) imagedestroy ($res_thumb); if(isset($res_img)) imagedestroy ($res_img); return $outfile; } public function watermark( $img,$pos='',$out_img='',$water_img='',$text='' ){ if(!$this->check($img) || !$this->watermark_on) return false; $water_img = $water_img ? $water_img : $this->water_img; //水印的开启状态 $waterimg_on = $this->check($water_img) ? 1 : 0; //判断是否在原图上操作 $out_img = $out_img ? $out_img : $img; //判断水印的位置 $pos = $pos ? $pos : $this->pos; //水印文字 $text = $text ? $text : $this->text; $img_info = getimagesize($img); $img_w = $img_info[0]; $img_h = $img_info[1]; //判断水印图片的类型 if( $waterimg_on ){ $w_info = getimagesize($water_img); $w_w = $w_info[0]; $w_h = $w_info[1]; if ( $img_w < $w_w || $img_h < $w_h ) return false; switch ( $w_info[2] ){ case 1: $w_img = imagecreatefromgif($water_img); break; case 2: $w_img = imagecreatefromjpeg($water_img); break; case 3: $w_img = imagecreatefrompng($water_img); break; } }else{ if( empty($text) || strlen($this->color)!=7 ) return FALSE; $text_info = imagettfbbox($this->size, 0, $this->font, $text); $w_w = $text_info[2] - $text_info[6]; $w_h = $text_info[3] - $text_info[7]; } //建立原图资源 switch ( $img_info[2] ){ case 1: $res_img = imagecreatefromgif($img); break; case 2: $res_img = imagecreatefromjpeg($img); break; case 3: $res_img = imagecreatefrompng($img); break; } //确定水印的位置 switch ( $pos ){ case 1: $x = $y =25; break; case 2: $x = ($img_w - $w_w)/2; $y = 25; break; case 3: $x = $img_w - $w_w; $y = 25; break; case 4: $x = 25; $y = ($img_h - $w_h)/2; break; case 5: $x = ($img_w - $w_w)/2; $y = ($img_h - $w_h)/2; break; case 6: $x = $img_w - $w_w; $y = ($img_h - $w_h)/2; break; case 7: $x = 25; $y = $img_h - $w_h; break; case 8: $x = ($img_w - $w_w)/2; $y = $img_h - $w_h; break; case 9: $x = $img_w - $w_w; $y = $img_h - $w_h; break; default : $x = mt_rand(25, $img_w - $w_w); $y = mt_rand(25, $img_h - $w_h); } //写入图片资源 if( $waterimg_on ){ imagecopymerge($res_img, $w_img, $x, $y, 0, 0, $w_w, $w_h, $this->pct); }else{ $r = hexdec(substr($this->color, 1,2)); $g = hexdec(substr($this->color, 3,2)); $b = hexdec(substr($this->color, 5,2)); $color = imagecolorallocate($res_img, $r, $g, $b); imagettftext($res_img, $this->size, 0, $x, $y, $color, $this->font, $text); } //生成图片类型 switch ( $img_info[2] ){ case 1: imagecreatefromgif($res_img,$out_img); break; case 2: //imagecreatefromjpeg($res_img,$out_img); imagejpeg($res_img,$out_img); break; case 3: imagepng($res_img,$out_img); break; } if(isset($res_img)) imagedestroy ($res_img); if(isset($w_img)) imagedestroy($w_img); return TRUE; } //验证图片是否存在 private function check($img){ $type = array('.jpg','.jpeg','.png','.gif'); $img_type = strtolower(strrchr($img, '.')); return extension_loaded('gd') && file_exists($img) && in_array($img_type, $type); } //获取缩略图的相关比例 //获取到图片的处理类型 private function thumb_size( $img_w,$img_h,$t_w,$t_h,$t_type){ //定义缩略图尺寸 $w = $t_w; $h = $t_h; //定义图片的原始尺寸 $cut_w = $img_w; $cut_h = $img_h; //当要目标图像小于缩略图的尺寸时； if( $img_w <= $t_w && $img_h < $t_h ){ $w = $img_w; $h = $img_h; }else{ if( !empty($t_type) && $t_type>0 ){ switch ( $t_type ){ //当宽度固定时 case 1: $h = $t_w/$img_w*$img_h; break; //高度固定时 case 2: $w = $t_h/$img_h*$img_w; break; //宽度固定，高度裁切 case 3: $cut_h = $img_w/$t_w*$t_h; break; //高度固定，宽度裁切 case 4: $cut_w = $img_h/$t_h*$t_w; break; //等比例缩放 default : if( ($img_w/$t_w) > ($img_h/$t_h) ){ $h = $t_w/$img_w*$t_h; }elseif( ($img_w/$t_w) < ($img_h/$t_h) ){ $w = $t_h/$img_h*$t_w; }else{ $w = $t_w; $h = $t_h; } } } } $arr[0] = $t_w; $arr[1] = $t_h; $arr[2] = $cut_w; $arr[3] = $cut_h; return $arr; } }

以上就是本文的全部内容，希望对大家学习PHP程序设计有所帮助。