System - Content Optimizer

Compatible Joomla: 3.0
Extension Type: plugin

User rating: 5 / 5
1000 total downloads
1000 last week

System - Content Optimizer

Optimizes images on content pages by caching, optimizing, and resizing them. It makes images look better and saves bandwidth!

Feature Info

Image support

This is intended for:

  • People who don’t know how to, or want to scale images on pages by hand.
  • People that don’t know how to convert from formats.

Rather than waste space this plug-in re-sizes, and optimizes all images!


Flowers.jpg - 3300px × 5100px at 3,333.2 KB

But you only want to display the image at 480px × 742px. That’s 3mb for each download! And browsers like IE make the images look ugly when scaled! If you are paying for bandwidth, or on a low bandwidth server, this can be a real pain!

Your options?

  1. Resize your images before you upload them all. (But others must have to know how to do this, and it takes time, and even more if you have many sizes of the same image.)
  2. Use this plug-in, and save yourself time!

Even if you use option 1, you should use this plug-in because it stops mistakes.

Flowers.jpg 3300px × 5100px at 3,333.2 KB:

After installing plug-in:

/plugins/content/contentoptimizer/Flowers.jpg is 480px × 742px at 51.75 KB:

This is all automatic now! Saving you time and money! This plug-in is a must have! More feature to come in the future! (Read about the alpha version)

Image Example

This is a demo that should work on a default install of Joomla 1.5

Editor settings: (You can use any editor of your choice. We do not provide an editor but Joomla comes with one by default.)



Html Tag:



Before Content Optmizer:



Note the Size of File and that is says "scaled to ..." under Image Dimensions.


After Content Optmizer:


Notice now the decresse is Size of File and no scaling it taking effect. You should not see "scaled to" if the plugin is activate, and the file should now be stored under /plugins/content/contentoptmizer.


-Disk write access for plugins/content/contentoptimizer/ (There will be database storage for the Alpha version)
-GD version 2+
-XMLReader is included and enabled as of PHP 5.1.0 by default.
-Your memory_limit must be high enough for your images to be processed. (Or the will be skiped)

Know working server providers

  • Godaddy Webhosting

(Contact if you wish to add your hosting provider to the list)

Version Info

Version 1.5.1.x

  • Image is re-sampled for matching height, width, and global quality.
  • Supports GIF,JPG, PNG (others may be suppoted)
  • Updates the resample images if you upload a replacement.
  • Global quality option for bandwidth low sites.

Gif notes:
If GIF support is enabled (by default) gif images are resampled, and animation is lost (GD has no support for animations). GIF images are saved, as PNG for finer alpha detail.

JavaScript and Styles are only supported in next 1.5.x Alpha

Version 1.5.2.x Alpha

  • Javascript is put in .JS files with hash
  • Styles are put in .CSS files with hash


I get a blank white page with content optimizer installed.

You need to activate error reporting in the Joomla backend to find out why. Most servers disable error by default and serve out a blank white page. To activate error reporting go into your backend and set Error Reporting to Maximum.


Then read trough Common Errors to find a solution.

Why do you use XMLreader insted of DOM?

The Document Object Model (DOM) is a part of almost all PHP distributions. But DOM is much slower then XMLreader. XMLreader is based off of libxml, and has had much more optimization (Since it is the "The XML library for Gnome")

Common Errors

Please contact if you need help with errors.

Some of my images convert but others don't

This is usually caused by PHP limiting the memmory avalible. It skips images that require to much memory to process.

Most often, the problem is that the memory_limit parameter in php.ini is set to something very conservative, like 8M (eight megabytes). Increase that setting and restart the web server.


See the PHP manual memory limit


Unable to load XMLReader

Warning: Content Optimizer: Unable to load the required class XMLReader! in /home/joomla/public_html/plugins/content/contentoptimizer.php on line 56

If you recive this error you have to install a version of PHP 5.1.x or above.

Also some PHP distributions come with XMLReader striped out, so you need to install a required package:


yum install -y php-xml && /sbin/service httpd restart

Why do I get "Fatal error: Allowed memory size of XXXXXX bytes exhausted"?

Most often, the problem is that the memory_limit parameter in php.ini is set to something very conservative, like 8M (eight megabytes). Increase that setting and restart the web server.

Of course, opening truly huge images can cause real memory problems, if several are open at once. 8,000 pixels times 8,000 pixels times four bytes for truecolor equals a walloping 256 megabytes.

See the PHP manual memory limit


Details From Version: Trunk r202