ImageJ is an open-source, Java-based image processing and display tool. It can read and write images in GIF, JPEG, BMP, PNG, PGM, FITS, ASCII and TIFF formats. Editing capabilities include image enhancement (e.g., smoothing, sharpening, edge detection, median filtering and thresholding), image manipulation (e.g., crop, scale, resize, rotate and flip) and even analyses (e.g., area measurement, mean brightness, standard deviation, min and max brightness and measurement of lengths and angles). A "macro" feature allows automation of processing tasks and a library of previously-created macros is available. Similarly, a library of "plugins" allows additional capabilities to be added.