最快的速度获取网页所有图片的长和宽。
<br /><br />function ranger($url){<br /> $headers = array( "Range: bytes=0-32768" );<br /> $curl = curl_init($url);<br /> curl_setopt($curl, CURLOPT_HTTPHEADER, $headers);<br /> curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);<br /> return curl_exec($curl);<br /> curl_close($curl);<br />}//curl设置<br /><br />require dirname(__FILE__) . '/simple_html_dom.php'; <br />//采用simple_html_dom.php分析HTML nod<br /><br />$url = 'http://www.huffingtonpost.com/';<br /><br />$html = file_get_html($url);<br />if($html->find('img')){<br /> foreach($html->find('img') as $element) {<br /> $raw = ranger($element->src);<br /> $im = @imagecreatefromstring($raw);<br /> $width = @imagesx($im);<br /> $height = @imagesy($im);<br /> if($width>=200||$height>=200){<br /> echo $element;//得出长大于大于200，宽大于等于200的图片<br /> }<br /> }<br />}<br /><br /> Copy after login
------解决思路---------------------- 也许能走个弯路，减轻服务器网络压力。
服务器负责解析HTML数据，统计image标签信息，最后将收集的文本数据送回客户端。
加载图片由客户端来完成，只需读取width,height属性，就完全可以获取图片的原始大小。
好处多多，不过可能的麻烦是防盗链
------解决思路---------------------- 顶楼上
PHP获取资源
javascript 取图片长和宽
------解决思路---------------------- 读取并解析 2.8秒
读取图片（138个） 27秒
找到 7 个
仅从优化代码出发，应该油水不大
可考虑多路并发
------解决思路---------------------- 读取并解析 3.6秒
启动读取图片进程（138个） 1.3秒
结果文件中记录数 7 个
http://s.huffpost.com/images/v/logos/v4/tagline.gif<br />http://s.huffpost.com/images/v/logos/v4/homepage.gif?v9<br />http://i.huffpost.com/gen/559399/thumbs/r-OLBERMANN-huge.jpg<br />http://s.huffpost.com/images/facebook_promo_connect.png?3<br />http://images.huffingtonpost.com/2012-04-04-michaeljfoxmarlo2SECOND.jpg<br />http://images.huffingtonpost.com/2012-04-05-Screenshot20120405at9.40.24AM.jpg<br />http://i.huffpost.com/gen/557914/thumbs/s-SCORSESE-large300.jpg<br /> Copy after login
原循环改为
foreach($html->find('img') as $element) {<br /> tenor("tenorcall.php?v=$element->src");<br /> }<br />}<br /> Copy after login
tenorcall.php
function ranger($url){<br /> $headers = array( "Range: bytes=0-32768" );<br /> $curl = curl_init($url);<br /> curl_setopt($curl, CURLOPT_HTTPHEADER, $headers);<br /> curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);<br /> return curl_exec($curl);<br /> curl_close($curl);<br />}//curl设置<br /><br /> $raw = ranger($_GET['v']);<br /> $im = @imagecreatefromstring($raw);<br /> $width = @imagesx($im);<br /> $height = @imagesy($im);<br /> if($width>=200<br><font color='#FF8000'>------解决思路----------------------</font><br>$height>=200){<br /> file_put_contents('tenorcall.txt', $_GET['v'].PHP_EOL, FILE_APPEND );//得出长大于大于200，宽大于等于200的图片<br /> }<br /> Copy after login
/**<br /> * 函数 tenor<br /> * 功能 启动一个url，但不等待返回<br /> * 参数 $page，待执行的页面程序<br /> * 返回 无<br /> **/<br />if(! function_exists('tenor')):<br />function tenor($page) {<br /> $host = $_SERVER["HTTP_HOST"];<br /> $fp = fsockopen($host, 80, $errno, $errmsg);<br /> if(!$fp) {<br /> echo "$errstr ($errno)<br>\n";<br /> } else {<br /> fputs($fp,"GET /$page HTTP/1.0\nHost: $host\n\n");<br /> fclose($fp);<br /> }<br />}<br />endif;<br /> Copy after login
代码还是原代码，非但没减少，反而增加了
但因为是并发，所以速度明显提高
值得注意的是：tenor 函数在某些web服务器中不能稳定的运行（比如iis6）原因不明
------解决思路---------------------- 我觉得，让客户端加载的方案是可行的，
客户端再将符合要求的图片信息提交给服务器，服务器端再验证一次后保存。。。
另外32768是怎么得来的？1-200不够吗
------解决思路---------------------- 学习！ 是用PHP获取图片url后直接读取图片的头信息吗？
------解决思路---------------------- pinterest那个pin功能创意很好,而且技术很简单，就是书签一串js代码，然后你点这个书签就相当于往当前页面文档append入一个js文件，这个js文件怎么写，就很简单了，主要就是遍历document.getElementsByTagName('img')
------解决思路---------------------- 本帖最后由 xuzuning 于 2012-04-06 15:25:06 编辑
138个照片并发，是不是就消耗了138个连接数 对
是否需要修改php.ini，增加连接数 否，连接是向外的，如果要改，也是对方改
CPU和内存开销如何 这个不太好测试
又 ，关于使用 js 判断的问题，由于他们没有给出代码，无法测试
自己写了两个方案都不理想，也就作罢了
用JS并发和直接PHP并发，2者从资源消耗角度来比，哪个会更少 资源消耗角度来比 都一样，都要完整的加载图片
不过前者是消耗客户端资源，后者是消耗服务器端资源
另外浏览器的机制不很了解，是否真的是并发也未可知
------解决思路---------------------- 这段代码在我这里大约 1.8秒，不计算 file_get_html ( $url ) 时间
$res [] = $url ;//$temp;
这样就是网络地址了
他是保存为本地文件后用 getimagesize 获取尺寸的
他应该是通过 curl 并发的，这个机制我不太了解
------解决思路---------------------- 但是 if(in_array($absUrl, $visited))continue; 这行报错。 Warning: in_array() expects parameter 2 to be array, null。
他的代码中并没有你说的出错的代码
应该是 file_get_html 在报错吧
file_get_html 使用 file_get_contents 读取 url 成功率较低
经常要刷两三次才可独到数据
------解决思路---------------------- JS可以通过获取图片的头部信息，而直接获取到图片的高度，
这种方式比用图片加载完成以后在获取他的搞定效率至少快10倍以上，
之前记得有在一个播客里面看到过这么个帖子来着，
没收藏，这一时半会的找不到了，郁闷啊~
------解决思路---------------------- 刚注册了http://pinterest.com。 它的做法就是用客户端来加载
点击Add 选择Pin ，贴上网址 http://www.huffingtonpost.com/
在chrome的Network中可以看到有一个请求
GET /pin/create/find_images/?url=http%253A%2F%2Fwww.huffingtonpost.com HTTP/1.1 返回的信息是一个json对象：
images: [http://s.huffpost.com/images/v/logos/v4/homepage.gif?v9,…]<br />0: "http://s.huffpost.com/images/v/logos/v4/homepage.gif?v9"<br />1: "http://s.huffpost.com/images/v/logos/v4/tagline.gif"<br />2: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />3: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />4: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />5: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />6: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />7: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />8: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />9: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />10: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />11: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />12: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />13: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />14: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />15: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />16: "http://s.huffpost.com/images/splash/t_mini-a.png"<br />17: "http://i.huffpost.com/gen/560770/thumbs/r-GSA-LAS-VEGAS-VIDEO-huge.jpg"<br />18: "http://s.huffpost.com/images/webslice12x12.png"<br />19: "http://s.huffpost.com/images/v/blog_column.png"<br />20: "http://s.huffpost.com/contributors/gary-hart/headshot.jpg"<br />21: "http://www.huffingtonpost.com/images/trans.gif"<br />22: "http://www.huffingtonpost.com/images/trans.gif"<br />23: "http://www.huffingtonpost.com/images/trans.gif"<br />24: "http://images.huffingtonpost.com/2012-04-06-campbellguitar.jpg"<br />25: "http://www.huffingtonpost.com/images/trans.gif"<br />26: "http://www.huffingtonpost.com/images/trans.gif"<br />27: "http://www.huffingtonpost.com/images/trans.gif"<br />28: "http://www.huffingtonpost.com/images/trans.gif"<br />29: "http://www.huffingtonpost.com/images/trans.gif"<br />30: "http://www.huffingtonpost.com/images/trans.gif"<br />31: "http://images.huffingtonpost.com/2012-04-06-Screenshot20120406at7.09.17PM.jpg"<br />32: "http://www.huffingtonpost.com/images/trans.gif"<br />33: "http://www.huffingtonpost.com/images/trans.gif"<br />34: "http://www.huffingtonpost.com/images/trans.gif"<br />35: "http://www.huffingtonpost.com/images/trans.gif"<br />36: "http://www.huffingtonpost.com/images/trans.gif"<br />37: "http://www.huffingtonpost.com/images/trans.gif"<br />38: "http://www.huffingtonpost.com/images/trans.gif"<br />39: "http://www.huffingtonpost.com/images/trans.gif"<br />40: "http://www.huffingtonpost.com/images/trans.gif"<br />41: "http://www.huffingtonpost.com/images/trans.gif"<br />42: "http://www.huffingtonpost.com/images/trans.gif"<br />43: "http://www.huffingtonpost.com/images/trans.gif"<br />44: "http://www.huffingtonpost.com/images/trans.gif"<br />45: "http://www.huffingtonpost.com/images/trans.gif"<br />46: "http://www.huffingtonpost.com/images/trans.gif"<br />47: "http://www.huffingtonpost.com/images/trans.gif"<br />48: "http://www.huffingtonpost.com/images/trans.gif"<br />49: "http://www.huffingtonpost.com/images/trans.gif"<br />50: "http://www.huffingtonpost.com/images/trans.gif"<br />51: "http://www.huffingtonpost.com/images/trans.gif"<br />52: "http://www.huffingtonpost.com/images/trans.gif"<br />53: "http://www.huffingtonpost.com/images/trans.gif"<br />54: "http://www.huffingtonpost.com/images/trans.gif"<br />55: "http://www.huffingtonpost.com/images/trans.gif"<br />56: "http://www.huffingtonpost.com/images/trans.gif"<br />57: "http://www.huffingtonpost.com/images/trans.gif"<br />58: "http://www.huffingtonpost.com/images/trans.gif"<br />59: "http://www.huffingtonpost.com/images/trans.gif"<br />60: "http://www.huffingtonpost.com/images/trans.gif"<br />61: "http://www.huffingtonpost.com/images/trans.gif"<br />62: "http://www.huffingtonpost.com/images/trans.gif"<br />63: "http://www.huffingtonpost.com/images/trans.gif"<br />64: "http://www.huffingtonpost.com/images/trans.gif"<br />65: "http://www.huffingtonpost.com/images/trans.gif"<br />66: "http://www.huffingtonpost.com/images/trans.gif"<br />67: "http://www.huffingtonpost.com/images/trans.gif"<br />68: "http://www.huffingtonpost.com/images/trans.gif"<br />69: "http://www.huffingtonpost.com/images/trans.gif"<br />70: "http://www.huffingtonpost.com/images/trans.gif"<br />71: "http://www.huffingtonpost.com/images/trans.gif"<br />72: "http://www.huffingtonpost.com/images/trans.gif"<br />73: "http://www.huffingtonpost.com/images/trans.gif"<br />74: "http://www.huffingtonpost.com/images/trans.gif"<br />75: "http://s.huffpost.com/images/blank.gif"<br />76: "http://s.huffpost.com/images/blank.gif"<br />77: "http://s.huffpost.com/images/blank.gif"<br />78: "http://s.huffpost.com/images/blank.gif"<br />79: "http://s.huffpost.com/images/blank.gif"<br />80: "http://s.huffpost.com/images/blank.gif"<br />81: "http://s.huffpost.com/images/blank.gif"<br />82: "http://s.huffpost.com/images/facebook_promo_connect.png?3"<br />83: "http://s.huffpost.com/images/loader.gif"<br />84: "http://www.huffingtonpost.com/images/trans.gif"<br />85: "http://www.huffingtonpost.com/images/trans.gif"<br />86: "http://www.huffingtonpost.com/images/trans.gif"<br />87: "http://www.huffingtonpost.com/images/trans.gif"<br />88: "http://www.huffingtonpost.com/images/trans.gif"<br />89: "http://www.huffingtonpost.com/images/trans.gif"<br />90: "http://s.huffpost.com/contributors/gary-hart/headshot.jpg"<br />91: "http://s.huffpost.com/contributors/mike-campbell/headshot.jpg"<br />92: "http://s.huffpost.com/contributors/roma-downey/headshot.jpg"<br />93: "http://s.huffpost.com/contributors/gavin-newsom/headshot.jpg"<br />94: "http://s.huffpost.com/contributors/sarah-shourd/headshot.jpg"<br />95: "http://s.huffpost.com/contributors/jacqueline-novogratz/headshot.jpg"<br />96: "http://s.huffpost.com/contributors/peggy-drexler/headshot.jpg"<br />97: "http://s.huffpost.com/contributors/mohamed-a-elerian/headshot.jpg"<br />98: "http://s.huffpost.com/contributors/bill-mckibben/headshot.jpg"<br />99: "http://s.huffpost.com/contributors/marlo-thomas/headshot.jpg"<br />100: "http://www.huffingtonpost.com/images/v/something_to_say_button.png"<br />101: "http://www.huffingtonpost.com/images/trans.gif"<br />102: "http://www.huffingtonpost.com/images/trans.gif"<br />103: "http://www.huffingtonpost.com/images/trans.gif"<br />104: "http://www.huffingtonpost.com/images/trans.gif"<br />105: "http://www.huffingtonpost.com/images/trans.gif"<br />106: "http://www.huffingtonpost.com/images/trans.gif"<br />107: "http://www.huffingtonpost.com/images/trans.gif"<br />108: "http://www.huffingtonpost.com/images/trans.gif"<br />109: "http://www.huffingtonpost.com/images/trans.gif"<br />110: "http://www.huffingtonpost.com/images/trans.gif"<br />111: "http://www.huffingtonpost.com/images/trans.gif"<br />112: "http://www.huffingtonpost.com/images/trans.gif"<br />113: "http://www.huffingtonpost.com/images/trans.gif"<br />114: "http://www.huffingtonpost.com/images/trans.gif"<br />115: "http://www.huffingtonpost.com/images/trans.gif"<br />116: "http://www.huffingtonpost.com/images/trans.gif"<br />117: "http://www.huffingtonpost.com/images/trans.gif"<br />118: "http://www.huffingtonpost.com/images/trans.gif"<br />119: "http://www.huffingtonpost.com/images/trans.gif"<br />120: "http://www.huffingtonpost.com/images/trans.gif"<br />121: "http://www.huffingtonpost.com/images/trans.gif"<br />122: "http://www.huffingtonpost.com/images/trans.gif"<br />123: "http://www.huffingtonpost.com/images/trans.gif"<br />124: "http://www.huffingtonpost.com/images/trans.gif"<br />125: "http://www.huffingtonpost.com/images/trans.gif"<br />126: "http://www.huffingtonpost.com/images/trans.gif"<br />127: "http://www.huffingtonpost.com/images/trans.gif"<br />128: "http://www.huffingtonpost.com/images/trans.gif"<br />129: "http://www.huffingtonpost.com/images/trans.gif"<br />130: "http://www.huffingtonpost.com/images/trans.gif"<br />131: "http://www.huffingtonpost.com/images/trans.gif"<br />132: "http://www.huffingtonpost.com/images/trans.gif"<br />133: "http://www.huffingtonpost.com/images/trans.gif"<br />134: "http://b.scorecardresearch.com/p?c1=2&c2=6723616&c3=&c4=&c5=front&c6=&c15=&cj=1"<br />135: "http://www.huffingtonpost.com//secure-us.imrworldwide.com/cgi-bin/m?ci=us-703240h&cg=0&cc=1&ts=noscript"<br />136: "http://vertical-stats.huffpost.com/?-1&&"<br />137: "http://www.huffingtonpost.com//pixel.quantserve.com/pixel/p-6fTutip1SMLM2.gif?labels=Home"<br />images_count: 138<br />redirected: false<br />status: "success"<br />title: "Breaking News and Opinion on The Huffington Post"<br />type: "text/html; charset=utf-8" Copy after login
几乎是服务器返回的同时，浏览器开始加载图片。chrome监控如下。黄色的那个线表示提交url获取图片资源，后面的就都是加载图片了，加载的速度还是取决于我这儿的网络。
由于http://pinterest.com/的JS代码经过压缩，且使用了JQuery，所以找起来特别费劲。其实具体怎么干就很简单，谁都能想到。遍历json数据，创建img标签对象，设置src属性，保存对象。剩下的浏览器就会自己完成。
------解决思路----------------------
引用:
引用:
什么对象？
你是说服务器返回的image链接的数据吗？不用保存呀。收到ajax请求后解析返回数据就完了
另外，浏览器加载外部资源都是异步。也就是说，不管是不是用的JQuery，都是异步加载的，相互不会影响。和老大写的php端的差不多。
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
