Help with phpThumb settings - any docs out there?

Can anyone direct me to information which explains what the modx settings in the phpThumb section do? In particular those relating to Hotlinking and Offsite Linking:

phpThumb Hotlinking Disabled : phpthumb_nohotlink_enabled
phpThumb Hotlinking Erase Image : phpthumb_nohotlink_erase_image
phpThumb Hotlinking Not Allowed Message : phpthumb_nohotlink_text_message
phpThumb Hotlinking Valid Domains : phpthumb_nohotlink_valid_domains
phpThumb Offsite Linking Disabled : phpthumb_nooffsitelink_enabled
phpThumb Offsite Linking Erase Image : phpthumb_nooffsitelink_erase_image
phpThumb Offsite Linking Require Referrer : phpthumb_nooffsitelink_require_refer
phpThumb Offsite Linking Not Allowed Message : phpthumb_nooffsitelink_text_message
phpThumb Offsite Linking Valid Domains : phpthumb_nooffsitelink_valid_domains

I am setting up a twitter feed, using the JSONDerulo addon. The docs for that state:

PHPThumbOf settings
Ensure you have the following in the "phpthumb_nohotlink_valid_domains" section:
Twitter profile avatars: *.twimg.com"

I presume this refers to the phpThumb settings, but I cannot find any reference to explain what this or related settings (above) actually mean or do.

In particular, I need to be aware of any security risks of changing any of these settings.

Thanks.


Revo 2.3.5
phpThumbOf installed

Check the docs for the phpThumb library. http://phpthumb.sourceforge.net/

Install pThumb instead of phpThumbOf, it's backwards-compatible to phpThumbOf but much better. You also have the option of using Ryan's Resizer library instead of phpThumb if you don't really need all of the features of phpThumb.

Ah great, thanks Susan.