Digital Images for the Information Professional

Citation

Calvert, P. (2009), "Digital Images for the Information Professional", The Electronic Library, Vol. 27 No. 4, pp. 737-739. https://doi.org/10.1108/02640470910979688

This is an excellent book. It is one of the best books in information management I have read for many years. My only concern is that its content appears from its title to be very narrow and almost esoteric, and that could harm its sales. What needs to be emphasised, however, is that the use of digital images is now mainstream in information management and all who work in libraries, galleries, museums and archives need the ability to recognise file types, manipulate images and add metadata to images. This might be for web pages, or in a digital library. There are now numerous ways we use digital images, so this book ought to be widely read and I highly recommend it.

After a short introduction there are seven main chapters. The chapter 2 is a history of digital images from the age of the telegraph up to about 2005 and it is useful because it gives some context for what follows. Chapter 3 is called “Digital image fundamentals” and that's exactly what the reader will find. Topics as basic as pixels, resolution, bit depth, image size and compression are all explained in some detail so that even someone such as his reviewer, who thought he knew most of this stuff, still learned a good deal. Knowledge of matters such as resolution and compression are essential for simple tasks such as posting images to web pages, and there is a lot more to even these basics than one first thinks. One topic that is of significance, though rarely explained as clearly as it is here, is the difference between bitmap and vector images.

The chapter 4 on image file formats is crammed full of information. An image file is more than just a set of pixel colour data, and knowing what else is in the file is necessary, for example, when exchanging image files across a network. It is also vital to understand how format conversion works and as this is something even beginners need to know, it is good that Melissa M. Terras has given such a clear explanation of what is involved and what quality loss you can expect in different circumstances. There is plenty of detail in the section on individual graphic formats, and again, here was some information that was totally new to me. This chapter closes with a section on imaging guidelines and standards.

Chapter 5 is called “Digital images and memory institutions”. The initial focus is on the “why” of digitisation in library, archives, museums and galleries. There follows a fairly lengthy history of digitisation, which again gives context. Next is a section headed “current issues in digitization”, which takes it for granted that memory institutions can and will digitize, so the focus must shift to doing it better and that, very largely, means finding out how users use digital images and how retrieval can be improved. It could be done by using Web 2.0 applications, but beyond prototype image tagging available on some web sites there is not really a lot happening. The chapter closes with some discussion of recent advanced technologies for image capture and image processing. Making better use of non‐destructive methods of image capture is still high on the list of desired technologies.

The subject of the chapter 6 is rather unexpected, being the management of personal digital image collections, but as the author points out, the vast number of images now being shared via channels such as Flick'r and Slide means that consideration must be given to how this wealth of material is organised and retrieved. Information managers need to learn how personal collections are maintained and used, for “the behaviour formed by users outside institutional environments will inform their behaviour and use of digital images provided by memory institutions” (p. 159). Users of Flick'r will expect a digital library to work in the same way.

The chapter on image metadata is thorough and even someone not interested in the technology of digital images must surely want to know how to describe images for storage and retrieval. Here, are descriptions of image metadata schemes such as DC, Exif, DIG35 and so on. The author discusses how to choose a metadata scheme for a digitization project and which controlled vocabulary might work best for each circumstance. The use of folksonomies is also discussed, as might be expected.

The chapter 7 examines some of the key current issues in digital imaging: particularly colour control, image quality, truth and imaging and copyright. None are easy, though as the first two have technological solutions they seem easier, whereas the finding moral clarity needed for telling the truth and using a sense of fair play is apparently more difficult for us humans to master.

This is a complete work. It covers all aspects of the subject relevant to the target readership, gives clarity to complex matters, includes all recent scholarship including a very long bibliography, and has a solid structure and a good index. All in all, this is a book that every information manager should read and I heartily congratulate Melissa M. Terras for her work and Ashgate for publishing it.