在露天图像上getimagesize

i'm working on a front display for an alfresco filled with pictures.

i'm building my pictures url like this :

http://myHost.com:8080/share/proxy/alfresco-noauth/api/node/content/workspace/SpacesStore/bf0a8b21-b8d9-487d-a529-dee8c49d7c6f/filetitle.jpg?alf_ticket=myTicket

where myHost is the server and myTicket is the ticket generated at this url :

http://myHost.com:8080/alfresco/service/api/login?u=login&pw=password

Picture is displaying correctly with this url, but i want to use phpthumb to resize it, and when i try to use it on my picture, i get an http 500 error on the script and the following log :

PHP Warning:  getimagesize(http://myHost.com:8080/share/proxy/alfresco-noauth/api/node/content/workspace/SpacesStore/bf0a8b21-b8d9-487d-a529-dee8c49d7c6f/filetitle.jpg?alf_ticket=myTicket): failed to open stream: HTTP request failed! HTTP/1.1 401 Non-Autorisé

I shouldn't hit the authentification, since my link has a valid ticket (I don't hit authentification when i display normally my picture)

Like Jeff states, Alfresco already creates thumbnails. So you can probably use:

http://myHost.com:8080/alfresco/service/api/node/workspace/SpacesStore/bf0a8b21-b8d9-487d-a529-dee8c49d7c6f/content/thumbnails/doclib?c=queue&ph=true&alf_ticket=myTicket

Desc from alfresco/templates/webscripts/org/alfresco/repository/thumbnail/thumbnail.get.desc.xml

  <url>/api/node/{store_type}/{store_id}/{id}/content{property}/thumbnails/{thumbnailname}?c={queueforcecreate?}&amp;ph={placeholder?}</url>  
  <url>/api/path/{store_type}/{store_id}/{id}/content{property}/thumbnails/{thumbnailname}?c={queueforcecreate?}&amp;ph={placeholder?}</url>
  <url>/api/node/{store_type}/{store_id}/{id}/content{property}/thumbnails/{thumbnailname}/{filename}?c={queueforcecreate?}&amp;ph={placeholder?}</url>  
  <url>/api/path/{store_type}/{store_id}/{id}/content{property}/thumbnails/{thumbnailname}/{filename}?c={queueforcecreate?}&amp;ph={placeholder?}</url>