Problems with single anonymous access aspx in Sharepoint 2010

I got a SharePoint Project which already works with开发者_如何学Go anonymous Access. Now I added an aspx-page which is used for streaming images. That aspx-page is added into a virtual directory Layouts\

Whenever I try to access that aspx-file Sharepoint does not allow anonymous access to that page even though all other pages viewable by the user work fine with anonymous access. Is there any way to change this behaviour?

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Two requirements must be met:

1. the page needs to inherit from the class UnsecuredLayoutsPageBase,
2. the property AllowAnonymousAccess needs to be overridden to return true.