As some of you have seen, I made the mistake of posting notes for Week 5... Oops. Here are my notes for Week 4.
Wikipedia article on Compression:
Data compression is a fascinating topic for me. I think it is particularly relevant in the context of some discussions that have occurred in and around LIS2000 regarding the digitization of printed materials. Many of us wonder at the effects that the digitization of books will have on the reader's ability to interact with them, but we've already got a good model for predicting certain effects: .mp3 representation of recorded artifacts. If you go to youtube and search for your favorite song, there's a good chance you'll come up with a file that has a fair amount of 'glassiness' to it, which sounds like a flanger and is usually most noticeable on hihats/cymbals and soprano/alto/high-bari backing vocals. (You usually won't run into this if you watch the official music video for a track, but it's very common among videos or tracks that were posted by amateur enthusiasts.) Near as I can tell, this doesn't bother most people; however, it's just about my biggest pet-peeve. The process of digitization and the use of lossy compression to reduce file size risks the quality of the artifact being digitized. If such quality loss is commonplace and often acceptable in digital music files, it makes sense to me that similar/analogous quality loss will be present in digital print material once it reaches the popularity that audio .mp3s already have... That worries me. To the bibliophile, part of the beauty of the reading experience might have much to do with the intricacies of an antique font, or with the fineness of the paper/binding, or even simply the feel of the page on his/her fingers-- much in the same way that the audiophile might find the most pleasure in a listening experience that is born of a four-tube, analog compressor (different than the type of compression we're talking about in this class) complete with subtle tape hiss in the high midrange and the soft anomalous transients that only occur with analog equipment. The audiophile can still listen to music on .mp3s, and the bibliophile can still read books, but the experience is qualitatively (and possible significantly) changed. It might be more convenient, it might even be necessary, but it's just not as good.
On another note, I found the numeric representation of lossy vs. lossless compression to be a very helpful visual aid, but one that is difficult to envision in terms of more complicated multimedia materials. I also found it particularly interesting to think that the digital representation of an artifact that does not show a pattern cannot be compressed. After having read that, it made perfect sense, but it's not something I'd thought of before.
Data Compression Basics Article:
I think the best point made in this article is that lossy compression preserves information, but not data. In order for this point to make sense, one must assume that the people viewing/listening to an uncompressed file will all necessarily get the same information from it. It's true that the range of human perception can be well represented by a bell curve, with most all of our perception abilities accounted for within the first two standard deviations from the mean. But, from a somewhat pedantic, purist viewpoint, it may well be the case that for some with unusual sensitivity, the most relevant/meaningful information might be conveyed by data lost during the compression process.
Digitizing Pittsburgh:
I think this is an example of a digitization project that was carried out very well. The images appear to be very high quality, and I wasn't surprised to read of the lengths the team went to in order to ensure reliability and interoperability among the differing institutions' metadata.
Youtube and Libraries:
The link on Courseweb wouldn't work for me, so I thought I'd post one that worked: here it is.
I thought the best part of this article is something it implies, as opposed to something it explicitly stated: new media and modes of media dissemination can play a vital role in the future of libraries and the way that patrons can interact with their library, be it a local public library, a university library, etc.. In order for the library as a concept to stay afloat, those of us working in and for them will need to keep abreast of social technologies in order to exploit them effectively.
Thanks for pointing out the downfalls of compression (especially lossy compression)- getting it in terms of sound quality hits home. I've definitely experienced that loss of quality, and it is certainly something to consider when we allow for compression- we need to make sure to stay focused on our ultimate goals and not allow the allure of saved space to lure us in!
ReplyDeleteThe kind of data-loss you're talking about here is indeed important. Part of me remains very concerned about losing things like sound quality or the feel of the page, for example. But I also wonder if the digital versions also play into things like outreach -- kind of like the youtube article: the youtube videos aren't intended to replace a visit to the library (or to its website) but rather to show people what is available and, maybe, how to use it. Online collections of pictures can be a kind of sample or introduction that helps people learn what is available -- so they can come in and handle the 'real thing' if they want. Granted, not always the case, or maybe even not often, since the original isn't always in a condition to be saved. But it strikes me as an important element of the digital collection -- and one that helps to mitigate some of the lossy v. lossless concerns.
ReplyDeleteI agree with your statement that the quality of items being digitized is compromised with the use of lossy compression. It is worrisome, but I think (and hope!) that the experience of holding and reading a book in one’s hands will always top that of using a Kindle or other reader. It may be a necessity at times though, for example, the archive I work in does not allow books for pleasure in the reading rooms, only those that are related to your research. The only way around this is to store your books on a Kindle if you wish to read while waiting for your pull. I’m actually surprised that a larger number of people don’t do this! I’ve only seen a few so far.
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