This is a lightweight extension for the well known phpThumb library. There are a lot of extensions out there providing a lot more functionality but they can be total overkill for just creating some thumbnails and saving them to disk. If you just want a simple wrapper for phpThumb then this extension is the right one.
In your main.php
'phpThumb'=>array( 'class'=>'ext.EPhpThumb.EPhpThumb', 'options'=>array(optional phpThumb specific options are added here) ),
$thumb=Yii::app()->phpThumb->create('../images/myImage.jpg'); $thumb->resize(100,100); $thumb->save('../images/thumb.jpg');
For more information visit the phpThumb documentation.