Image processing Skills: none IT concepts: image processing program, operation, data type, image file type, data compression This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.

Image processing in context

Image processing in IT literacy context Internet concepts Applications Technology Implications for Individuals Organizations Society Internet skills Application development Content creation Text Images Audio Video

When data types went mainstream Decade Data Type 1950s Numeric 1960s Alphanumeric 1970s Text 1980s Images, speech 1990s Music, low-quality video 2000s High-quality video

Image processing in 1964 Ivan Sutherland operating Sketchpad, an early example of interactive, personal computing with a graphical user interface, but it ran on a multimillion dollar computer.

Alan Kay shows a video of Sketchpad http://www.youtube.com/watch?v=mOZqRJzE8xg&feature=related

Image processing examples

Subtle retouching of a photo Photographer and retoucher Michael Kubeisy believes the trick with Photoshop is knowing when to stop. Here are changes made on this image: 1 Her crow's feet were made softer with the healing brush, which seamlessly corrects imperfections by matching texture and lighting; 2 The whites of her eyes were brightened using the dodge tool; 3 Some flyaway strands hairs on the top of her head were removed; 4 Johnson's teeth were slightly whitened, again using the dodge tool; 5 Her skin was smoothed out and given a soft glow; 6 A blemish was removed from her collarbone; 7 Some lines around her neck were softened, and the carotid artery in her neck was erased. (Michael Kubeisy with Digital-Ops.) http://www.latimes.com/features/lifestyle/la-ig-photoshop2-2009aug02,0,3129812.story Crow's feet made softer Whites of her eyes brightened Flyaway strands hairs on the top of her head removed Teeth slightly whitened Skin smoothed out and given a soft glow Blemish removed from her collarbone Lines around her neck softened and the carotid artery in her neck erased

Not so subtle From worth1000.com

Abraham Lincoln’s head on John Calhoun’s body http://www.nytimes.com/slideshow/2009/08/23/weekinreview/20090823_FAKE_SS_index.html A Brief History of Photo Fakery You don’t need a computer, but it makes it a lot easier.

Image processing operations and programs

Word and image processing operations Text data Image data Select text Cut text Copy text Move text Delete text Change fonts Change text size Change text color Change footnote style Check spelling Compress a text file Etc. etc. Select a portion of the image Crop an image Copy a portion of an image Move a portion of an image Delete a portion of an image Resize an image Rotate an image Change image brightness Change image contrast Change colors Compress an image file Etc. etc. Can you think of other word and image processing operations?

Popular programs Word processing Image processing Adobe photoshop (proprietary, desktop) Paint.net (open source, desktop) Photoshop.com (network) Microsoft Word (proprietary, desktop) Open Office (open source, desktop) Google Docs (network) There are many other image processing programs, and they are often included with cameras. Can you think of other examples?

Which image processor should you use? Photoshop – used by most professional photographers and designers Paint.net – many features and is fine for this class and most work Gimp – open source program with the features of Photoshop Paint – is free with Windows, but is lame. Network image processors – not ready for prime time, but keep watching Any other that you have already and are familiar with To get these and others, see the resources section at: http://bpastudio.csudh.edu/fac/lpress/netapps/image/

Image processing file types

Flat versus photographic images Logos and other images with a limited color palette Photographic images with continuous tone variation Different file types for different types of image

Common Internet image file types .gif: Graphic Interchange Format, used for logos, cartoons, and other flat art with up to 256 different colors .png: Portable Network Graphics, gif replacement (more colors), cannot do animation .bmp: Microsoft Bitmap, an uncompressed format used for photographic images .jpeg (or .jpg): Joint Photographers Expert Group, a compressible format used for photographic images Compression – making the file smaller, but reducing image quality – more later.

Flat versus photographic images .png or .gif if animation or compatibility is an issue .jpg or .bmp if file size is not an issue

Processing different file types Nearly every image processing program can handle the common image file types. You can use your image processing program to convert from one type to another. See this article or Wikipedia for more information.