Other functions

xxf:decode-iso9075-14()

xxf:decode-iso9075-14($value as xs:string) as xs:string

The xxf:decode-iso9075-14() function decodes a string according to ISO 9075-14:2003.

xxf:doc-base64()

xxf:doc-base64($href as xs:string) as xs:string

The xxf:doc-base64() function reads a resource identified by the given URL, and returns the content of the file as a Base64-encoded string. It is a dynamic XPath error if the resource cannot be read.

xxf:doc-base64-available()

xxf:doc-base64-available($href as xs:string) as xs:boolean

The xxf:doc-base64-available() function reads a resource identified by the given URL. It returns true() if the file can be read, false() otherwise.

xxf:encode-iso9075-14()

xxf:encode-iso9075-14($value as xs:string) as xs:string

The xxf:encode-iso9075-14() function encodes a string according to ISO 9075-14:2003. The purpose is to escape any character which is not valid in an XML name.

xxf:image-metadata()

[SINCE Orbeon Forms 4.4]

xxf:image-metadata($content as xs:anyURI, $name as xs:string) as xs:item?

Access basic image metadata.

The function returns the empty sequence if the URL is empty or the metadata requested is not found.

• $content: URL pointing to an image

• $name: metadata property name

  • width: image width in pixels, returns an xs:integer if found

  • height: image height in pixels, returns an xs:integer if found

  • mediatype: image mediatype based on the content, returns an xs:string of image/jpeg, image/png, image/gif or image/bmp (the formats universally supported by browsers) if found

NOTE: The function dereferences the content of the URL when called. Accesses to local files are likely to be faster than remote files.

The following example validates that the image is within 10% of a 1x1 aspect ratio:

<xf:bind
  ref="uploaded-image"
  constraint="
    abs(
        xs:decimal(xxf:image-metadata(., 'width')) div
        xs:decimal(xxf:image-metadata(., 'height')) - 1.0
    ) le 0.1"/>