SalsaJ

SalsaJ is a software tool developed in Java in order to aid individuals open, view and edit astronomical images (FITS), as well as regular ones in popular formats such as GIF, JPG and BMP. It can also open images from a user-input URL.
The interface is fairly simple to use, regardless of your previous experience with computers. It contains a menu bar, several shortcut buttons and each opened image is displayed in a new window.
It is possible to undo actions, cut, copy, paste, clear and fill in elements, as well as repeat commands or revert to the original image. An image calculator is integrated, which enables you to perform different operations with two pictures, such as add, subtract, multiply, divide and show differences.
Similar single picture operations are also available, you can rotate, flip, duplicate, crop or scale pictures, and view information such as title, width and height (expressed in pixels), bits per pixel and display range.
This utility lets you use a surface plotter or curve fitter, view a graphical representation of tonal distribution in photos (histogram) and a calibration bar. Tweaking the brightness and contrast levels is also possible, as well as adding text and geometrical shapes (rectangle, oval, polygon etc.), and using a magnifying glass and a color picker.
Once all configurations have been set, you can print the resulted image or save it to the hard drive as TIFF, GIF, JPG, BMP, FITS, ZIP and RAW files.
All in all, SalsaJ is a useful piece of software when it comes to viewing and modifying astronomical and usual images, with many options to take advantage of. However, it might benefit from an update.