File Formats Blog

The results of a University of Connecticut study on how libraries are using JPEG2000 format are available online. Thanks to Digitization 101 for the link.

Labels: JPEG2000

The Joint Photographic Experts Group (JPEG) has issued a press release on developments from the 47th WG1 meeting in San Francisco. Here are a few highlights:

• JPEG XR (formerly Microsoft HD Photo) has advanced toward becoming an international standard.
• There is lots of new stuff and more solid versions of existing stuff in JPEG2000, including specifications for security, access by mobile and wireless devices, inclusion of OCR results in image files, and 3-D data.
• Work is starting on a color version of JBIG2, even though the "B" in JBIG stands for "bitonal."

All of this taken together gives a certain feeling of feature bloat.

Labels: conferences, JBIG, JPEG, JPEG2000

From Taubman and Marcellin, JPEG2000: Image Compression Fundamentals, Standards and Practice: "Such a compression system is said to be 'idempotent' because the operations of compression and decompression may be repeated indefinitely without effecting the result produced by their first application."

Of course, an idempotent operation should "effect" the same result every time it is applied. But I guess it's tough finding proofreaders to whom that sentence is anything but technobabble.

Labels: humor, JPEG2000

Live-blogging this isn't. I didn't get a chance to post from London, and then I spent the next week having fun around Germany. But here are some notes on what happened, with emphasis on file format and metadata issues.

Participants got a nice thick book of proceedings to take home, providing more information than the twenty-minute presentations did. I think the presentations should have gotten half an hour each, even though that would have meant fewer of them.

Trends in archives and libraries are toward JPEG2000 as an image storage format, even though it has to be converted before browsers can use it. Oya Rieger, talking about digitization of books, cited the smaller file size compared to JPEG, and the support of archival features such as incorporation of metadata into the file.

PREMIS is gaining traction as a format for preservation metadata. For instance, the British Library is using PREMIS 1.1, along with METS and MODS, for an eJournal archiving project. The article is available on the D-Lib site.

Stephen Abrams gave a presentation on JHOVE2, which is still in the design and prototyping stages. It's getting obvious from various discussions that the problems in JHOVE are becoming more of a concern. JHOVE2 will only partially replace JHOVE, since budgetary considerations limit the number of format modules planned. It will separate identification from validation; this means that if a file is a slightly flawed TIFF, it will tell you rather than just saying it's a "bitstream." It will also add assessment, which I don't fully understand, but will incorporate locally defined acceptability criteria. I think this means that if you can deal with certain common but minor deviations from a format specification, you can tell JHOVE2 that such files are acceptable.

JHOVE2 will get away from the one file, one object idea. In its model, a file may contain more than one document, or a document may be spread across multiple files. It was also mentioned that there will be API-level support for the edited of objects, but third parties will have to supply any editors. If my notes are complete, JHOVE will support JPEG2000, TIFF, WAVE, SGML, UTF-8, XML, PDF, shapefile, and ICC profiles. AIFF, GIF, HTML, and JPEG won't be supported. (GIF surprises me a bit; it's so simple that I'm sure someone will write a JHOVE2 module for it.)

JHOVE2 will use SourceForge for distribution and issue tracking, as JHOVE now does (though JHOVE is just a spare-time project without support right now). There's a public information site on JHOVE2 available right now, so far without a lot of content. The paper on JHOVE2 presented in the conference proceedings is available online.

Labels: conferences, JHOVE, JPEG2000, metadata