F/OSS and Visuals I: Image Tampering
In the age of Photoshop and other programs that allow easy image editing, one necessary digital literacy is the ability to discern whether an image might have been tampered with. Two examples of the usefulness of this literacy come from snopes.com, the popular urban legend web site maintained by Don and Barbara Mikkulsky. Mikkulsky (2007) debunked an e-mail chain containing a picture of a woman on Who Wants to be a Millionaire? guessing that an elephant was larger than the moon. Closer investigation revealed that the question had been digitally inserted into footage of the contestant struggling with a different question on the show. Mikkulsky (2005) debunks another image showing a boy crying in front of a tombstone on which the inscription reads “Santa Claus,” implying that the popular Christmas icon is dead. The same crying boy was later found on a billboard in Florida, showing that the Santa image had been manipulated. These are slightly pernicious examples of the use of image manipulation to deceive gullible people; future examples could be far more malicious.
What many users do not understand about digital images is that they are not static images, but rather mosaics, made up of a multitude of individual pixels that can be altered at will to make the image look entirely different. According to Doughty (1998), computer graphics are divided into raster images, which are drawn from individual pixels, and vector images, which are constructed mathematically from points and the paths between them. This distinction is important to students and professionals who work with images. Because vector graphics are constructed using a mathematical algorithm, they can be manipulated and resized without damaging the image, whereas raster images degrade when resized and look heavily pixelated.
The sophistication of present-day image editing programs means that Microsoft Paint, a rudimentary raster editor, is simply insufficient to teach students how to understand digital images. Adobe Photoshop is the industry standard for raster editors, and can be a powerful tool in helping students learn how to manipulate images, but it is also part of Adobe's Creative Suite, which is expensive; even on its own. GIMP, or the GNU Image Manipulation Program, is an open source raster editor that contains many of the same functions as Photoshop, Corel's Paintshop Pro, and other proprietary raster editors, according to GIMP Team (2009). With such similar features, GIMP could be used in classrooms to teach students the basics of raster graphics as well as pixel-level image manipulation, teaching them the understanding of how images can be altered as with the examples above. Additionally, Fossfor.us features a vector editor known as Inkscape, which provides similar functionality to Adobe's Illustrator program. Inkscape could be used to teach students about vector editing in a similar fashion. Teaching students how digital images work, and how to work with different types, empowers them to work comfortably with images in digital settings. Students with this comfort level can competently produce multimodal digital texts that engage readers on textual, visual, and even auditory levels.
Previous: Background III: F/OSS Resources and Composition Next: F/OSS and Visuals II: Visual Rhetoric