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This element is optional but there are applications that can leverage this element in metadata so IdP operators are encouraged to provide a link to a logo that meets the following requirements. For example, a discovery service may use a visual cue (i.e., a logo) instead of or in addition to the Display Name.
The logo must be specified using an HTTPS URL. The host in the URL must reside in a domain owned by the IdP. These are the only strict requirements of a logo URL in metadata.
The actual size of the logo may vary. You will be asked to enter the actual width and height of the logo (in pixels). The application will select your logo (or not) based on the actual width and height entered into metadata.
Usable Generally useful logos are thought to have the following characteristics:
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- the logo should have a transparent background
- the logo should have a landscape orientation (width > height)
- an aspect ratio between 4:3 and 16:9 is considered optimal
- the logo should have a minimum width of 100 pixels
- the logo should have a minimum height of 75 pixels
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