There are a very large number of applications, free and commercial, for manipulating image files. The four below are a mix of free and commercial, Windows/Mac and Linux based, and simple and complex. For most tasks, you will only need to use one of these packages, but each has its own advantages and disadvantages.

ImageMagick

ImageMagick is not just one tool but rather a suite of freely available command-line tools for creating, editing and manipulating raster image files. ImageMagick tools can translate, flip, mirror, rotate, scale, shear, and transform images, adjust image colors, apply special effects, or draw text, lines, polygons, ellipses, and B├ęzier curves. The suite is available for Windows, Linux, Mac OS, and Unix, and they are installed locally on the Shared Computing Cluster (SCC).

Examples:
Add a blue border around image
convert -border 10x10 -bordercolor "#6699ff" fan.png fan2.png
Add a caption/attribution
convert -font helvetica -fill red -pointsize 14 -draw 'text 446,404 "sondak@bu.edu"' fan2.png fan3.png

Multi-colored fan 1 Multi-colored fan 2 Multi-colored fan 3

Adobe Photoshop

Photoshop window

Adobe Photoshop is a commercial package available primarily for Windows and Mac OS. We do not have this installed on our systems but it is an extremely popular and powerful package for working with image files. A large range of image formats is supported and the program has a full and involved GUI to access the many features.

XV

XV image viewer

XV is a small, free image viewer. Although mostly a viewing problem, it can also be used to crop, resize, and convert images from one file format to another.

The GIMP

The GIMP is a free package with similar functionality to Adobe Photoshop and is available on the SCC, it is accessible by default, not requiring a module.