许久以前写过一篇也是关于高性能PHP图片动态裁剪方案的文章，那文章使用的是Nginx Cache和rewrite实现的，当然再加上CDN，那个方案存在一个问题就是图片并没有实际生成，而是以二进制的形式存在缓存中。如果缓存失效了那么还需要请求PHP再次生成。如果说到区别这是我暂且认为的吧。
利用空余时间，新增了静态生成图片支持，支持对图片3种模式切换，在门户网站自动对图片尺寸进行裁剪，减少服务器带宽，理论上应该也满足了业务的需求吧，图片裁剪使用了Imagick组件。
一、思路再现：
1、先写好请求服务器生成图片动态脚本，主要就是对图片进行等比缩放计算+裁剪。
2、确定你想要生成的url规则，比如http://www.domain.com/www/300×200-1/test.jpg。
3、对浏览器做缓存处理。
4、结束。
二、动态裁剪PHP脚本
代码如下:
/**
* Author pony_chiang
* 高性能图像裁剪方案
* 需要PHP-imagick扩展
*/
ini_set ( "memory_limit","80M" );// 请求地址比如 http://yourdomain.com/resize.PHP?site=www&width=300&height=200&mode=2&path=uploadfile/helloworld.png
// Nginx重写规则 rewrite ^([^\.]*)/s/(.*)/(\d+)x(\d+)-(\d)/(.*) $1/s/resize.PHP?site=$2&width=$3&height=$4&mode=$5&path=$6 last;$path = trim ( $_GET ['path'] );
$mode = intval ( $_GET ['mode'] );
$site = trim ( $_GET ['site'] );
$width = intval ( $_GET ['width'] );
$height = intval ( $_GET ['height'] );$site_list = array ('www' => '/mnt/webroot/test/' );$orig_dir = dirname ( __FILE__ );
if (! array_key_exists ( $site,$site_list )) {
header ( 'HTTP/1.1 400 Bad Request' );
exit ();
}if ($mode > 3 || $mode < 0) {
header ( 'HTTP/1.1 400 Bad Request' );
exit ();
}$orig_file = $site_list [$site] . $path;
if (! file_exists ( $orig_file )) {
header ( 'HTTP/1.1 404 Not Found' );
exit ();
}$file_ext = '.' . pathinfo ( $path,PATHINFO_EXTENSION );$file_name = basename ( $path,$file_ext );
$save_path = "{$orig_dir}/{$site}/{$width}x{$height}-{$mode}/{$path}";
$save_dir = dirname ( $save_path );if (! file_exists ( $save_dir ))
wpx_mkdir ( $save_dir );$target_width = $width;
$target_height = $height;$new_width = $target_width;
$new_height = $target_height;
$image = new Imagick ( $orig_file );
list ( $orig_width,$orig_height,$type,$attr ) = getimagesize ( $orig_file );if ($mode == "0") {
//等比缩放图像
$new_height = $orig_height * $new_width / $orig_width;
if ($new_height > $target_height) {
$new_width = $orig_width * $target_height / $orig_height;
$new_height = $target_height;
}
} else if ($mode == "2") {
// 放大并裁剪图像
$desired_aspect = $target_width / $target_height;
$orig_aspect = $orig_width / $orig_height; if ($desired_aspect > $orig_aspect) {
$trim = $orig_height - ($orig_width / $desired_aspect);
$image->cropImage ( $orig_width,$orig_height - $trim,$trim / 2 );
error_log ( "HEIGHT TRIM $trim" );
} else {
$trim = $orig_width - ($orig_height * $desired_aspect);
$image->cropImage ( $orig_width - $trim,$trim / 2,0 );
}
}$image->resizeImage ( $new_width,$new_height,imagick::FILTER_LANCZOS,1 );
$image->writeImage ( $save_path );
header ( 'Content-Type: image/jpeg' );
header ( 'Last-Modified: ' . gmdate ( 'D,d M Y H:i:s' ) . ' GMT' );
echo file_get_contents ( $save_path );
return true;// 循环生成目录
function wpx_mkdir($dir,$mode = 0777) {
if (is_dir ( $dir ) || @mkdir ( $dir,$mode ))
return true;
if (! wpx_mkdir ( dirname ( $dir ),$mode ))
return false;
return @mkdir ( $dir,$mode );
}
* Author pony_chiang
* 高性能图像裁剪方案
* 需要PHP-imagick扩展
*/
ini_set ( "memory_limit","80M" );// 请求地址比如 http://yourdomain.com/resize.PHP?site=www&width=300&height=200&mode=2&path=uploadfile/helloworld.png
// Nginx重写规则 rewrite ^([^\.]*)/s/(.*)/(\d+)x(\d+)-(\d)/(.*) $1/s/resize.PHP?site=$2&width=$3&height=$4&mode=$5&path=$6 last;$path = trim ( $_GET ['path'] );
$mode = intval ( $_GET ['mode'] );
$site = trim ( $_GET ['site'] );
$width = intval ( $_GET ['width'] );
$height = intval ( $_GET ['height'] );$site_list = array ('www' => '/mnt/webroot/test/' );$orig_dir = dirname ( __FILE__ );
if (! array_key_exists ( $site,$site_list )) {
header ( 'HTTP/1.1 400 Bad Request' );
exit ();
}if ($mode > 3 || $mode < 0) {
header ( 'HTTP/1.1 400 Bad Request' );
exit ();
}$orig_file = $site_list [$site] . $path;
if (! file_exists ( $orig_file )) {
header ( 'HTTP/1.1 404 Not Found' );
exit ();
}$file_ext = '.' . pathinfo ( $path,PATHINFO_EXTENSION );$file_name = basename ( $path,$file_ext );
$save_path = "{$orig_dir}/{$site}/{$width}x{$height}-{$mode}/{$path}";
$save_dir = dirname ( $save_path );if (! file_exists ( $save_dir ))
wpx_mkdir ( $save_dir );$target_width = $width;
$target_height = $height;$new_width = $target_width;
$new_height = $target_height;
$image = new Imagick ( $orig_file );
list ( $orig_width,$orig_height,$type,$attr ) = getimagesize ( $orig_file );if ($mode == "0") {
//等比缩放图像
$new_height = $orig_height * $new_width / $orig_width;
if ($new_height > $target_height) {
$new_width = $orig_width * $target_height / $orig_height;
$new_height = $target_height;
}
} else if ($mode == "2") {
// 放大并裁剪图像
$desired_aspect = $target_width / $target_height;
$orig_aspect = $orig_width / $orig_height; if ($desired_aspect > $orig_aspect) {
$trim = $orig_height - ($orig_width / $desired_aspect);
$image->cropImage ( $orig_width,$orig_height - $trim,$trim / 2 );
error_log ( "HEIGHT TRIM $trim" );
} else {
$trim = $orig_width - ($orig_height * $desired_aspect);
$image->cropImage ( $orig_width - $trim,$trim / 2,0 );
}
}$image->resizeImage ( $new_width,$new_height,imagick::FILTER_LANCZOS,1 );
$image->writeImage ( $save_path );
header ( 'Content-Type: image/jpeg' );
header ( 'Last-Modified: ' . gmdate ( 'D,d M Y H:i:s' ) . ' GMT' );
echo file_get_contents ( $save_path );
return true;// 循环生成目录
function wpx_mkdir($dir,$mode = 0777) {
if (is_dir ( $dir ) || @mkdir ( $dir,$mode ))
return true;
if (! wpx_mkdir ( dirname ( $dir ),$mode ))
return false;
return @mkdir ( $dir,$mode );
}
三、Nginx.conf配置
代码如下:
server {
listen 80;
server_name test.yourdomain.com;
root /mnt/webroot/test;
index index.PHP;
expires 30d; location /s {
#只有当没有生成这张图片时才调用动态裁剪
if (!-e $request_filename) {
rewrite ^([^\.]*)/s/(.*)/(\d+)x(\d+)-(\d)/(.*) $1/s/resize.PHP?site=$2&width=$3&height=$4&mode=$5&path=$6 last;
break;
}
} error_page 404 403 402 500 502 503 504 /404.html;
location = /404.html {
} location ~ \.PHP$ {
fastcgi_pass 127.0.0.1:9000;
fastcgi_index index.PHP;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
include fastcgi_params;
}}
listen 80;
server_name test.yourdomain.com;
root /mnt/webroot/test;
index index.PHP;
expires 30d; location /s {
#只有当没有生成这张图片时才调用动态裁剪
if (!-e $request_filename) {
rewrite ^([^\.]*)/s/(.*)/(\d+)x(\d+)-(\d)/(.*) $1/s/resize.PHP?site=$2&width=$3&height=$4&mode=$5&path=$6 last;
break;
}
} error_page 404 403 402 500 502 503 504 /404.html;
location = /404.html {
} location ~ \.PHP$ {
fastcgi_pass 127.0.0.1:9000;
fastcgi_index index.PHP;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
include fastcgi_params;
}}
PS：在文章的末尾我要特别强调一点是关于浏览器缓存的文章，不管你是否是通过PHP生成的图片也好，还是使用Nginx缓存生成的图片也罢，在PHP代码中添加一行
代码如下:
