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 various 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

Adobe Photoshop

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 is a small, free image viewer available on the SCC. 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 available on the SCC and is a free package with similar functionality to Adobe Photoshop.