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Images do not extract to epub OPF manifest - solved

  • 1.  Images do not extract to epub OPF manifest - solved

    Posted 06-04-2011 06:21
    Hi all,


    I have found the problem with image filenames not appearing
    in the OPF manifest.



    For each figure, I had one mediaobject containing two imageobjects:
    each imageobject had a role attribute to allow selection of the image for
    different output – one with role=”fo” and the other with
    role=”xhtml”. When I
    split each imageobject into its own mediaobject, the image filename appeared
    in
    the manifest. So when transforming to epub, the rule is: separate
    mediaobjects
    for each image in the XML.



    This is a trap: having multiple imageobjects in one
    mediaobject still produces valid XML. It also allows FO, XHTML and epub
    transformations without showing any errors. The images appear correctly in
    the
    resulting XHTML pages. I am sure you could create a valid epub like this
    too,
    but it would obviously be missing metadata.



    Maybe the epub transformation should fail if the DocBook
    markup does not satisfy the test of there being separate
    “mediaobject/imageobject/imagedata”
    for each image, because it would be missing metadata.



    Thanks,

    Dave Gardiner