浅谈php扩展imagick
PHP建图通常都用GD库,因为是内置的不需要在服务器上额外安装插件,所以用起来比较省心,但是如果你的程序主要的功能就是处理图像,那麼就不建议用GD了,因为GD不但低效能而且能力也比较弱,佔用的系统资源也颇多,另外GD的creatfrom也有bug,而imagick却是一个很好的替代品,为此最近把我的一个项目由GD改成了imagick,但是改完之后出现了一些状况在此分享给大家.
首先说一下我这边出现的状况:
状况一:需要重写图像操作class
状况二:imagick多线程时会导致cpu使用率暴增到100%
在此顺便提一下imagick在centos6.4的安装方法:
1、安装ImageMagick
wgethttp://soft.vpser.net/web/imagemagick/ImageMagick-6.7.1-2.tar.gz tarzxvfImageMagick-6.7.1-2.tar.gz cdImageMagick-6.7.1-2/ ./configure--prefix=/usr/local/imagemagick--disable-openmp make&&makeinstall ldconfig
测试ImageMagick是否可以正常运行：
/usr/local/imagemagick/bin/convert-version
2、安装PHP扩展：imagick
wgethttp://pecl.php.net/get/imagick-3.0.1.tgz tarzxvfimagick-3.0.1.tgz cdimagick-3.0.1/ /usr/local/php/bin/phpize ./configure--with-php-config=/usr/local/php/bin/php-config--with-imagick=/usr/local/imagemagick make&&makeinstall ldconfig vi/usr/local/php/etc/php.ini 添加：extension="imagick.so"
重启lnmp
/root/lnmpreload
接下来我们针对上述两个状况分别提出解决办法:
状况一的解决办法如下:
/**
Imagick图像处理类
用法:
//引入Imagick物件
if(!defined('CLASS_IMAGICK')){require(Inc.'class_imagick.php');}
$Imagick=newclass_imagick();
$Imagick->open('a.gif');
$Imagick->resize_to(100,100,'scale_fill');
$Imagick->add_text('1024i.com',10,20);
$Imagick->add_watermark('1024i.gif',10,50);
$Imagick->save_to('x.gif');
unset($Imagick);
/**/
define('CLASS_IMAGICK',TRUE);
classclass_imagick{
private$image=null;
private$type=null;
//构造
publicfunction__construct(){}
//析构
publicfunction__destruct(){
if($this->image!==null){$this->image->destroy();}
}
//载入图像
publicfunctionopen($path){
if(!file_exists($path)){
$this->image=null;
return;
}
$this->image=newImagick($path);
if($this->image){
$this->type=strtolower($this->image->getImageFormat());
}
$this->image->stripImage();
return$this->image;
}
/**
图像裁切
/**/
publicfunctioncrop($x=0,$y=0,$width=null,$height=null){
if($width==null)$width=$this->image->getImageWidth()-$x;
if($height==null)$height=$this->image->getImageHeight()-$y;
if($width<=0||$height<=0)return;
if($this->type=='gif'){
$image=$this->image;
$canvas=newImagick();
$images=$image->coalesceImages();
foreach($imagesas$frame){
$img=newImagick();
$img->readImageBlob($frame);
$img->cropImage($width,$height,$x,$y);
$canvas->addImage($img);
$canvas->setImageDelay($img->getImageDelay());
$canvas->setImagePage($width,$height,0,0);
}
$image->destroy();
$this->image=$canvas;
}else{
$this->image->cropImage($width,$height,$x,$y);
}
}
/**
更改图像大小
参数:
$width:新的宽度
$height:新的高度
$fit:适应大小
'force':把图像强制改为$widthX$height
'scale':按比例在$widthX$height内缩放图片,结果不完全等於$widthX$height
'scale_fill':按比例在$widthX$height内缩放图片,没有像素的地方填充顏色$fill_color=array(255,255,255)(红,绿,蓝,透明度[0不透明-127全透明])
其他:智能模式,缩放图片并从正中裁切$widthX$height的大小
注意:
$fit='force','scale','scale_fill'时输出完整图像
$fit=图像方位时输出指定位置部份的图像
字母与图像的对应关系如下:
north_west north north_east
west center east
south_west south south_east
/**/
publicfunctionresize_to($width=100,$height=100,$fit='center',$fill_color=array(255,255,255,0)){
switch($fit){
case'force':
if($this->type=='gif'){
$image=$this->image;
$canvas=newImagick();
$images=$image->coalesceImages();
foreach($imagesas$frame){
$img=newImagick();
$img->readImageBlob($frame);
$img->thumbnailImage($width,$height,false);
$canvas->addImage($img);
$canvas->setImageDelay($img->getImageDelay());
}
$image->destroy();
$this->image=$canvas;
}else{
$this->image->thumbnailImage($width,$height,false);
}
break;
case'scale':
if($this->type=='gif'){
$image=$this->image;
$images=$image->coalesceImages();
$canvas=newImagick();
foreach($imagesas$frame){
$img=newImagick();
$img->readImageBlob($frame);
$img->thumbnailImage($width,$height,true);
$canvas->addImage($img);
$canvas->setImageDelay($img->getImageDelay());
}
$image->destroy();
$this->image=$canvas;
}else{
$this->image->thumbnailImage($width,$height,true);
}
break;
case'scale_fill':
$size=$this->image->getImagePage();
$src_width=$size['width'];
$src_height=$size['height'];
$x=0;
$y=0;
$dst_width=$width;
$dst_height=$height;
if($src_width*$height>$src_height*$width){
$dst_height=intval($width*$src_height/$src_width);
$y=intval(($height-$dst_height)/2);
}else{
$dst_width=intval($height*$src_width/$src_height);
$x=intval(($width-$dst_width)/2);
}
$image=$this->image;
$canvas=newImagick();
$color='rgba('.$fill_color[0].','.$fill_color[1].','.$fill_color[2].','.$fill_color[3].')';
if($this->type=='gif'){
$images=$image->coalesceImages();
foreach($imagesas$frame){
$frame->thumbnailImage($width,$height,true);
$draw=newImagickDraw();
$draw->composite($frame->getImageCompose(),$x,$y,$dst_width,$dst_height,$frame);
$img=newImagick();
$img->newImage($width,$height,$color,'gif');
$img->drawImage($draw);
$canvas->addImage($img);
$canvas->setImageDelay($img->getImageDelay());
$canvas->setImagePage($width,$height,0,0);
}
}else{
$image->thumbnailImage($width,$height,true);
$draw=newImagickDraw();
$draw->composite($image->getImageCompose(),$x,$y,$dst_width,$dst_height,$image);
$canvas->newImage($width,$height,$color,$this->get_type());
$canvas->drawImage($draw);
$canvas->setImagePage($width,$height,0,0);
}
$image->destroy();
$this->image=$canvas;
break;
default:
$size=$this->image->getImagePage();
$src_width=$size['width'];
$src_height=$size['height'];
$crop_x=0;
$crop_y=0;
$crop_w=$src_width;
$crop_h=$src_height;
if($src_width*$height>$src_height*$width){
$crop_w=intval($src_height*$width/$height);
}else{
$crop_h=intval($src_width*$height/$width);
}
switch($fit){
case'north_west':
$crop_x=0;
$crop_y=0;
break;
case'north':
$crop_x=intval(($src_width-$crop_w)/2);
$crop_y=0;
break;
case'north_east':
$crop_x=$src_width-$crop_w;
$crop_y=0;
break;
case'west':
$crop_x=0;
$crop_y=intval(($src_height-$crop_h)/2);
break;
case'center':
$crop_x=intval(($src_width-$crop_w)/2);
$crop_y=intval(($src_height-$crop_h)/2);
break;
case'east':
$crop_x=$src_width-$crop_w;
$crop_y=intval(($src_height-$crop_h)/2);
break;
case'south_west':
$crop_x=0;
$crop_y=$src_height-$crop_h;
break;
case'south':
$crop_x=intval(($src_width-$crop_w)/2);
$crop_y=$src_height-$crop_h;
break;
case'south_east':
$crop_x=$src_width-$crop_w;
$crop_y=$src_height-$crop_h;
break;
default:
$crop_x=intval(($src_width-$crop_w)/2);
$crop_y=intval(($src_height-$crop_h)/2);
}
$image=$this->image;
$canvas=newImagick();
if($this->type=='gif'){
$images=$image->coalesceImages();
foreach($imagesas$frame){
$img=newImagick();
$img->readImageBlob($frame);
$img->cropImage($crop_w,$crop_h,$crop_x,$crop_y);
$img->thumbnailImage($width,$height,true);
$canvas->addImage($img);
$canvas->setImageDelay($img->getImageDelay());
$canvas->setImagePage($width,$height,0,0);
}
}else{
$image->cropImage($crop_w,$crop_h,$crop_x,$crop_y);
$image->thumbnailImage($width,$height,true);
$canvas->addImage($image);
$canvas->setImagePage($width,$height,0,0);
}
$image->destroy();
$this->image=$canvas;
}
}
/**
添加图片水印
参数:
$path:水印图片(包含完整路径)
$x,$y:水印座标
/**/
publicfunctionadd_watermark($path,$x=0,$y=0){
$watermark=newImagick($path);
$draw=newImagickDraw();
$draw->composite($watermark->getImageCompose(),$x,$y,$watermark->getImageWidth(),$watermark->getimageheight(),$watermark);
if($this->type=='gif'){
$image=$this->image;
$canvas=newImagick();
$images=$image->coalesceImages();
foreach($imageas$frame){
$img=newImagick();
$img->readImageBlob($frame);
$img->drawImage($draw);
$canvas->addImage($img);
$canvas->setImageDelay($img->getImageDelay());
}
$image->destroy();
$this->image=$canvas;
}else{
$this->image->drawImage($draw);
}
}
/**
添加文字水印
参数:
$text:水印文字
$x,$y:水印座标
/**/
publicfunctionadd_text($text,$x=0,$y=0,$angle=0,$style=array()){
$draw=newImagickDraw();
if(isset($style['font']))$draw->setFont($style['font']);
if(isset($style['font_size']))$draw->setFontSize($style['font_size']);
if(isset($style['fill_color']))$draw->setFillColor($style['fill_color']);
if(isset($style['under_color']))$draw->setTextUnderColor($style['under_color']);
if($this->type=='gif'){
foreach($this->imageas$frame){
$frame->annotateImage($draw,$x,$y,$angle,$text);
}
}else{
$this->image->annotateImage($draw,$x,$y,$angle,$text);
}
}
/**
图片存档
参数:
$path:存档的位置和新的档案名
/**/
publicfunctionsave_to($path){
$this->image->stripImage();
switch($this->type){
case'gif':
$this->image->writeImages($path,true);
return;
case'jpg':
case'jpeg':
$this->image->setImageCompressionQuality($_ENV['ImgQ']);
$this->image->writeImage($path);
return;
case'png':
$flag=$this->image->getImageAlphaChannel();
//如果png背景不透明则压缩
if(imagick::ALPHACHANNEL_UNDEFINED==$flagorimagick::ALPHACHANNEL_DEACTIVATE==$flag){
$this->image->setImageType(imagick::IMGTYPE_PALETTE);
$this->image->writeImage($path);
}else{
$this->image->writeImage($path);
}unset($flag);
return;
default:
$this->image->writeImage($path);
return;
}
}
//直接输出图像到萤幕
publicfunctionoutput($header=true){
if($header)header('Content-type:'.$this->type);
echo$this->image->getImagesBlob();
}
/**
建立缩小图
$fit为真时,将保持比例并在$widthX$height内產生缩小图
/**/
publicfunctionthumbnail($width=100,$height=100,$fit=true){$this->image->thumbnailImage($width,$height,$fit);}
/**
给图像添加边框
$width:左右边框宽度
$height:上下边框宽度
$color:顏色
/**/
publicfunctionborder($width,$height,$color='rgb(220,220,220)'){
$color=newImagickPixel();
$color->setColor($color);
$this->image->borderImage($color,$width,$height);
}
//取得图像宽度
publicfunctionget_width(){$size=$this->image->getImagePage();return$size['width'];}
//取得图像高度
publicfunctionget_height(){$size=$this->image->getImagePage();return$size['height'];}
//设置图像类型
publicfunctionset_type($type='png'){$this->type=$type;$this->image->setImageFormat($type);}
//取得图像类型
publicfunctionget_type(){return$this->type;}
publicfunctionblur($radius,$sigma){$this->image->blurImage($radius,$sigma);}//模糊
publicfunctiongaussian_blur($radius,$sigma){$this->image->gaussianBlurImage($radius,$sigma);}//高斯模糊
publicfunctionmotion_blur($radius,$sigma,$angle){$this->image->motionBlurImage($radius,$sigma,$angle);}//运动模糊
publicfunctionradial_blur($radius){$this->image->radialBlurImage($radius);}//径向模糊
publicfunctionadd_noise($type=null){$this->image->addNoiseImage($type==null?imagick::NOISE_IMPULSE:$type);}//添加噪点
publicfunctionlevel($black_point,$gamma,$white_point){$this->image->levelImage($black_point,$gamma,$white_point);}//调整色阶
publicfunctionmodulate($brightness,$saturation,$hue){$this->image->modulateImage($brightness,$saturation,$hue);}//调整亮度,饱和度,色调
publicfunctioncharcoal($radius,$sigma){$this->image->charcoalImage($radius,$sigma);}//素描效果
publicfunctionoil_paint($radius){$this->image->oilPaintImage($radius);}//油画效果
publicfunctionflop(){$this->image->flopImage();}//水平翻转
publicfunctionflip(){$this->image->flipImage();}//垂直翻转
}
状况二的解决办法如下:
首先用/usr/local/imagemagick/bin/convert-version指令查看一下输出内容是否已经开啟了多线程,Features:的值为空说明是单线程,如果Features:的值是openMP说明是多线程.imagick的多线程模式有一个bug,他会导致多核心的cpu使用率瞬间飆升到100所以一定要使用它的单线程模式才行.
Version:ImageMagick6.7.1-22014-05-29Q16http://www.imagemagick.org Copyright:Copyright(C)1999-2011ImageMagickStudioLLC Features:
上边是我配置正确时显示的结果,如果没有配置正确会显示下边的结果
Version:ImageMagick6.7.1-22014-05-29Q16http://www.imagemagick.org Copyright:Copyright(C)1999-2011ImageMagickStudioLLC Features:openMP
第一种结果是单线程模式,第二种结果是多线程模式,因为imagick的多线程模式有bug,所以如果您刚开始是用多线程模式安装的imagick那就必须要yumremoveimagemagick将其卸载掉重新安装才行.
经过重写class,重装imagick之后一切正常,而且处理图像的效能比之以前有了大幅提升