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Plugin API/Filter Reference/login head

The "login_head" filter can be used to filter the logo image in wordpress login page. By default this logo is of wordpress.

A plugin can register as a content filter with the code:

add_filter("login_head","custom_function_name");

Where "custom_function_name" is the function WordPress will call when the content is being retrieved.

You can use this as a plugin if you wish to apply this filter to your WPMU blog network or

if you wish to distribute your theme with your logo then you can also use this in your WordPress theme's function.php

Example

In the below example the default logo is changed to custom logo. 

function custom_logo(){
    echo '<style type="text/css">
	h1 a {background-image:url(http://domain.com/your-logo.png) !important; margin:0 auto;}
	</style>';
}
add_filter('login_head', 'custom_logo');
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