Screencapture/thumbnail from user submitted url

[eware3000]

If anyone can help that would be awesome.

Not sure if this is possible, but wanted to know if there is a way to do the following with php and also how to do it:
When a user submits their url (via a form), I want to be able to go and capture a screenshot of said url, thus creating a thumbnail image of it, then store in db for inclusion to a gallery - I know this can be done manually, but I see it easily getting to hard to manage for me.

Is this possible?

Thanks for any help.
phpStudent

[alimadzi]

Here you go...

http://blog.thepimp.net/index.php/post/2007/04/17/Screen-capture-with-PHP-and-GD

I haven't actually tried this, but it appears to work judging from the comments. Good luck!

[MarkR]

This is extremely difficult, you will run into many problems. You may think it's possible on win32 using the Internet explorer method described above - but I think you'll find that that doesn't give you enough control.

Some things to consider:
- Security considerations - will the browser you use execute Javascript or other things
- Popups, dialogue boxes - will dialogue boxes and popups cause your application to hang waiting for the browser to complete? WHat happens if the user enters a URL requiring HTTP authentication, with a redirect (or redirect loop), HTTPS, goes to a FTP site, redirects to a file: URL, has a dodgy SSL certificate, requires NTLM authentication, contains frames, contains an object which the browser would normally use a helper app to display etc?
- If you are capturing the physical (or virtual) screen of a real session, how are you going to stop two requests coming in at once? Are you going to queue the requests and use a daemon?
- How are you detecting / handling errors which happen?
- What is the resource usage of these embedded browsers? Will it hose your server?
- Do you support plugins (Flash, Java, active X etc)
- How do you detect when the page is fully loaded? What is "fully loaded" anyway? Do you have to wait for backgrounds to load, etc? (NB: In my implementation I found this to be a problem)

---

I wrote an implementation which used a XUL application running in Xulrunner (Mozilla) to create a socket server application which listened for requests from PHP. It sent the results back asynchronously into PHP (Via HTTP, base64 encoded PNGs I think), and PHP further processed them.

This was complicated but worked well.

There are a LOT of issues. You need to be really careful.

Whatever you do, you have to be very careful that the browser doesn't crash / hang / spit out a dialogue box.

I found that I had to override various XPCOM objects in Mozilla to prevent dialogue boxes which would otherwise impede progress. I don't know if you get that level of control in MSIE.

Mark

[Kudose]

Funny. I just did a basic implementation of something similar to this for personal use yesterday. It takes a URL captures it as current desktop resolution in full screen mode then resizes it to 600x450.

You need a "posts" directory one level below the script. This is for Windows btw.

<?php
function microtime_float()
{
    list($usec, $sec) = explode(" ", microtime());
    return ((float)$usec + (float)$sec);
}

$time_start = microtime_float();
$root_dir = dirname(__FILE__);
$img_dir = $root_dir.'\\posts';

if(isset($_POST)){
  $browser = new COM("InternetExplorer.Application");
  $handle = $browser->HWND;
  $browser->Visible = true;
  $browser->FullScreen = true;
  $browser->StatusBar = false;

  $site = $_POST['site'];

  $w = 600;
  $h = 400;

set_time_limit(60);
try {
  $browser->Navigate($site);
  while($browser->Busy) {
    com_message_pump(1000);
  }
  com_message_pump(1000);
  $im = imagegrabwindow($handle, 0);
  $time = time(0);
  imagepng($im, $img_dir.'\\'.$time.".png");
  imagedestroy($im);

  $source = imagecreatefrompng($img_dir.'\\'.$time.".png");
  $dest = imagecreate($w, $h);
  list($ow, $oh) = getimagesize($img_dir.'\\'.$time.".png");
  imagecopyresized($dest, $source, 0, 0, 0, 0, $w, $h, $ow, $oh);
  imagepng($dest, $img_dir.'\\'.$time.".png");
  imagedestroy($dest);
  imagedestroy($source);

  $msg = 'Success';
} catch(Exception $e){
  echo $e->getMessage();
}

  $browser->Quit();
}
?>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
  <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
  <title></title>
  </head>
  <body>
  <?php if(isset($_POST)) echo $msg.'<br /><br />'; ?>
    <form name="myForm" action="post.php" method="post">
      URL:&nbsp;<input type="text" name="site" value="http://" />
      <br /><br />
      <input type="submit" value="  Submit  " name="submitForm" />
    </form>
  </body>
</html>
<?php 
$time_end = microtime_float();
$time = $time_end - $time_start;
echo 'Took '.$time.' seconds.';
?>

[MarkR]

I'd like to point out to anyone reading this thread: The COM implementations mentioned in their current form are not suitable for a production site.

Firstly, it probably won't work if your web server runs as a service. Secondly, it won't work in a multiuser environment. Thirdly, it probably has serious performance and security problems.

Do NOT use such an implementation in a production environment without RIGOROUS testing- be very careful, you could easily break or compromise your server.

Mark

[Kudose]

Good to know.