I hope to show that you can reduce the size of images without any visible loss of quality. If the images are going into Powerpoint files, that will greatly reduce the file size and make them easier to work with. If the images are going on the web, the page will then load much quicker.
The presentation introduces the terminology of image processing, how you generate digital images, how the data is stored, some of the different formats (bmp, gif, tiff, jpeg, etc) and what format is appropriate for what application. It does not cover specific image processing programs, but I will say something about how to reduce the filesize without making the image look terrible.
Digital images may come from
- Digital camera - we have a Canon PowerShot S3 IS
in the department.
It may be borrowed, or I can take
photos for you.
See http://www.howstuffworks.com/digital-camera.htm for more information on how digital cameras work and some pointers on what to look for when buying one.
- Captured from video
- Scanned photographs
- Scanned line drawings - the public use
scanner is attached to a PC in the lower PC suite
See http://www.scantips.com for tips on scanning
- Drawn on the computer - in a package such as AutoCAD
- Grabbed from web pages - if you right click on an image on a web page, it brings up a menu. One option is to save the image to disk. (Copyright rules apply to images taken from the web as they would if you took an illustration from a book)
- Clip art
Software for image processing
Digital images may be used in
- Microsoft Office Picture Manager - this is part of MS Office and is on all the public PCs (PhotoEditor in older versions of Office)
- Adobe Photoshop Lite - PC with scanner and photocard reader, lower PC suite
- PaintShop Pro - PCs, 30 day trial version free
- NIH Image - Macs and PCs, free
image processing and analysis program
- Graphic Converter - shareware for Macs (Shareware means you can download it from the web and try it out, but then you're supposed to pay for it)