php建圖通常都用GD庫,因為是內置的不需要在服務器上額外安裝插件,所以用起來比較省心,但是如果你的程序主要的功能就是處理圖像,那麼就不建議用GD了,因為GD不但低效能而且能力也比較弱,佔用的系統資源也頗多,另外GD的creatfrom???也有bug,而imagick卻是一個很好的替代品,為此最近把我的一個項目由GD改成了imagick,但是改完之後出現了一些狀況在此分享給大家.

首先說一下我這邊出現的狀況:

狀況一:需要重寫圖像操作class

狀況二:imagick多線程時會導致cpu使用率暴增到100%

在此順便提一下imagick在centos6.4的安裝方法:

1、安装ImageMagickwget http://soft.vpser.net/web/imagemagick/ImageMagick-6.7.1-2.tar.gztar zxvf ImageMagick-6.7.1-2.tar.gzcd ImageMagick-6.7.1-2/./configure --PRefix=/usr/local/imagemagick --disable-openmpmake && make installldconfig测试ImageMagick是否可以正常运行：/usr/local/imagemagick/bin/convert -version2、安装PHP扩展：imagickwget http://pecl.php.net/get/imagick-3.0.1.tgztar zxvf imagick-3.0.1.tgzcd imagick-3.0.1//usr/local/php/bin/phpize./configure --with-php-config=/usr/local/php/bin/php-config --with-imagick=/usr/local/imagemagickmake && make installldconfigvi /usr/local/php/etc/php.ini添加：extension = "imagick.so"重启lnmp/root/lnmp reload

接下來我們針對上述兩個狀況分別提出解決辦法:

狀況一的解決辦法如下:

  1 /**  2     Imagick圖像處理類  3     用法:  4         //引入Imagick物件  5         if(!defined('CLASS_IMAGICK')){require(Inc.'class_imagick.php');}  6         $Imagick=new class_imagick();  7         $Imagick->open('a.gif');  8         $Imagick->resize_to(100,100,'scale_fill');  9         $Imagick->add_text('1024i.com',10,20); 10         $Imagick->add_watermark('1024i.gif',10,50); 11         $Imagick->save_to('x.gif'); 12         unset($Imagick); 13 /**/ 14  15 define('CLASS_IMAGICK',TRUE); 16 class class_imagick{ 17     private $image=null; 18     private $type=null; 19  20     // 構造 21     public function __construct(){} 22  23     // 析構 24     public function __destruct(){ 25         if($this->image!==null){$this->image->destroy();} 26     } 27  28     // 載入圖像 29     public function open($path){ 30         if(!file_exists($path)){ 31             $this->image=null; 32             return ; 33         } 34         $this->image=new Imagick($path); 35         if($this->image){ 36             $this->type=strtolower($this->image->getImageFormat()); 37         } 38         $this->image->stripImage(); 39         return $this->image; 40     } 41  42     /** 43         圖像裁切 44     /**/ 45     public function crop($x=0,$y=0,$width=null,$height=null){ 46         if($width==null) $width=$this->image->getImageWidth()-$x; 47         if($height==null) $height=$this->image->getImageHeight()-$y; 48         if($width<=0 || $height<=0) return; 49  50         if($this->type=='gif'){ 51             $image=$this->image; 52             $canvas=new Imagick(); 53  54             $images=$image->coalesceImages(); 55             foreach($images as $frame){ 56                 $img=new Imagick(); 57                 $img->readImageBlob($frame); 58                 $img->cropImage($width,$height,$x,$y); 59  60                 $canvas->addImage($img); 61                 $canvas->setImageDelay($img->getImageDelay()); 62                 $canvas->setImagePage($width,$height,0,0); 63             } 64  65             $image->destroy(); 66             $this->image=$canvas; 67         }else{ 68             $this->image->cropImage($width,$height,$x,$y); 69         } 70     } 71  72     /** 73         更改圖像大小 74         參數: 75             $width:新的寬度 76             $height:新的高度 77             $fit: 適應大小 78                 'force': 把圖像強制改為$width X $height 79                 'scale': 按比例在$width X $height內縮放圖片,結果不完全等於$width X $height 80                 'scale_fill':按比例在$width X $height內縮放圖片,沒有像素的地方填充顏色$fill_color=array(255,255,255)(红,绿,蓝,透明度[0不透明-127全透明]) 81                 其他:智能模式,縮放圖片並從正中裁切$width X $height的大小 82         注意: 83             $fit='force','scale','scale_fill'時輸出完整圖像 84             $fit=圖像方位時輸出指定位置部份的圖像 85         字母與圖像的對應關係如下: 86             north_west   north   north_east 87             west         center        east 88             south_west   south   south_east 89     /**/ 90     public function resize_to($width=100,$height=100,$fit='center',$fill_color=array(255,255,255,0)){ 91         switch($fit){ 92         case 'force': 93             if($this->type=='gif'){ 94                 $image=$this->image; 95                 $canvas=new Imagick(); 96  97                 $images=$image->coalesceImages(); 98                 foreach($images as $frame){ 99                     $img=new Imagick();100                     $img->readImageBlob($frame);101                     $img->thumbnailImage($width,$height,false);102 103                     $canvas->addImage($img);104                     $canvas->setImageDelay($img->getImageDelay());105                 }106                 $image->destroy();107                 $this->image=$canvas;108             }else{109                 $this->image->thumbnailImage($width,$height,false);110             }111             break;112         case 'scale':113             if($this->type=='gif'){114                 $image=$this->image;115                 $images=$image->coalesceImages();116                 $canvas=new Imagick();117                 foreach($images as $frame){118                     $img=new Imagick();119                     $img->readImageBlob($frame);120                     $img->thumbnailImage($width,$height,true);121 122                     $canvas->addImage($img);123                     $canvas->setImageDelay($img->getImageDelay());124                 }125                 $image->destroy();126                 $this->image=$canvas;127             }else{128                 $this->image->thumbnailImage($width,$height,true);129             }130             break;131         case 'scale_fill':132             $size=$this->image->getImagePage();133             $src_width=$size['width'];134             $src_height=$size['height'];135 136             $x=0;137             $y=0;138 139             $dst_width=$width;140             $dst_height=$height;141 142             if($src_width*$height > $src_height*$width){143                 $dst_height=intval($width*$src_height/$src_width);144                 $y=intval(($height-$dst_height)/2);145             }else{146                 $dst_width=intval($height*$src_width/$src_height);147                 $x=intval(($width-$dst_width)/2);148             }149 150             $image=$this->image;151             $canvas=new Imagick();152 153             $color='rgba('.$fill_color[0].','.$fill_color[1].','.$fill_color[2].','.$fill_color[3].')';154             if($this->type=='gif'){155                 $images=$image->coalesceImages();156                 foreach($images as $frame){157                     $frame->thumbnailImage($width,$height,true);158 159                     $draw=new ImagickDraw();160                     $draw->composite($frame->getImageCompose(),$x,$y,$dst_width,$dst_height,$frame);161 162                     $img=new Imagick();163                     $img->newImage($width,$height,$color,'gif');164                     $img->drawImage($draw);165 166                     $canvas->addImage($img);167                     $canvas->setImageDelay($img->getImageDelay());168                     $canvas->setImagePage($width,$height,0,0);169                 }170             }else{171                 $image->thumbnailImage($width,$height,true);172 173                 $draw=new ImagickDraw();174                 $draw->composite($image->getImageCompose(),$x,$y,$dst_width,$dst_height,$image);175 176                 $canvas->newImage($width,$height,$color,$this->get_type());177                 $canvas->drawI