On 27/12/2012 18:52, Kevin M Randall wrote:
It seems to me that the concept of manifestation is no less important when considering online resources. And they are certainly not always “exactly the same files”. For things such as electronic journals, there can be very significant differences between manifestations (the one found on the publisher’s web site vs. Ebsco vs. Gale, etc.). And then there are also ebooks, where you have versions for Kindle, for Nook, etc. Sound files can be in various formats and at different bit rates. Graphic files can be in different formats and resolutions. Many books, films, sound recordings, etc. have been digitally converted and remastered multiple times, and there are very real differences between the versions–differences which can be significant, perhaps even critical, to the user. Compared to the print world, one could argue that we are dealing with a greater number of manifestations, and there will always be a need to distinguish between them, on both the managerial side (e.g. selection and acquisition) and the user side (obtaining files whose formats and features meet the user’s needs).
This is a good point, but what I meant is that there is a difference between a file and how it is rendered on a particular machine. This can be seen clearly with XML and XSLT, where the XML file is unique and static, while the XSLT renders it into any kind of format that you want. Therefore, a single XML file can be rendered as HTML, RDF, PDF, TXT, or almost any way that you want. To see a simple working example, look at http://www.w3schools.com/xsl/tryxslt.asp?xmlfile=cdcatalog&xsltfile=cdcatalog, where you can see how the XML on the left side can be rendered in all kinds of ways by the XSLT on the right side to create the final product below. Change the part in the right-hand side
to something like
<td><xsl:value-of select=”<td><xsl:value-of select=”title”/></td>”/></td>
to see how the final product can be changed very easily. There are a lot more possibilities than this very simple example but it shows a bit how it can work. This process can even produce sound files and probably much more in the future. I know that some newspapers and magazines work with XML so that they only need to generate one file of “content” and other files will generate the printed version vs. the online version. This saves them a lot of work.
This demonstrates the problems of cataloging based on manifestations. If you have cataloged several thousand HTML manifestation records, and the owners of the XML add only a single XSLT that creates PDFs (or MOBI, or EPUB), the cataloger would have to create several thousand records for each manifestation of each PDF or EPUB or whatever. Such a situation is obviously unworkable and why I said that people are actually looking at the same file (XML).
This also obviously has consequences for the “item” in the WEMI, and why I think the entire FRBR structure is based on physical materials and not particularly applicable to online documents, which are much more flexible than anything we have seen before.