Thursday, April 19, 2012

Capture image with imagegrabscreen and Wamp


I'm trying to capture a local web page with imagegrabscreen but I only get a black screenshot. I tried almost every solution from questions here on SO and others sites and nothing works.



I'm using and done the following:



  • Windows 7 64bit

  • Wamp 2.2a 64bit

  • PHP 5.3.8

  • gd2 (version: "bundled 2.0.34 compatible") is installed and enabled.

  • Allowed the apache service to interact with the desktop.

  • I don't have a secondary display or anything.




<?php
$im = imagegrabscreen();
imagepng($im, "myscreenshot.png");
imagedestroy($im);
?>



And all I get is a black image 1024x768 png.


Source: Tips4all

3 comments:

  1. You can do it. I did this. I didn't use WAMP. I used everything separate. I have all PHP, MySQL and Apache setup.

    Here are the steps.


    Stop the Apache server service. You can do this by invoking

    NET STOP Apache2.2


    or you can open the services.msc then stop it.
    Copy the Apache2.2 folder out of C:\. Put it somewhere where you have full access. Like Documents or in other drive. I put it in K:. To be sure you have full access,


    Recursively get ownership of the Apache directory.
    Make sure You have Full control marked tick on security tab of the Apache2.2 folder.
    This new Apache's configuration file httpd.conf will contain a lot of hardcoded paths. Like C:\apache software foundation\apache2.2. Just replace those with your new path. In my case it was K:\Apache2.2.

    At this moment your Apache Server Service should be stopped. So 80 port will not be blocked. And you'll have your own Apache at your own territory (directory).
    Open a console window and go to your Apache home where htdocs folder resides along with some other folders using cd
    Run bin\httpd.exe. This means you are running Apache. You have full access to your desktop. You can do anything, so do httpd.exe
    Open your web page. With following code.

    <?php
    header("Content-type: image/png");
    $im = imagegrabscreen();
    imagepng($im);
    imagedestroy($im);
    exit(0);
    ?>

    You'll see the image.

    ReplyDelete
  2. This is from a comment on the php.net manual page for imagegrabscreen(); try it and see if it fixes the issue, it sounds like what you're running into:


    For this to work your Apache service must be set to 'Allow service to interact with desktop' otherwise you will just get a blank image.


    To actually make the change:


    Run the command services.msc as Admin.
    Find the Apache service in the list, right click and select Properties
    Click the Log On tab
    Change the service to use a local system account if it isn't already
    Check the box that says Allow this service to interact with the desktop.
    Restart the Apache service.

    ReplyDelete
  3. If you are having trouble with imagegrabscreen() you may want to try a windows command line tool to capture the screen like boxcutter. Then use the PHP exec() function to call it. ex:

    <?php

    $exec = exec('boxcutter -f image.png'); // -f is full screen option

    ReplyDelete