ImageJ – Java image processing program

ImageJ is a public domain, Java-based image processing program. This utility can display, edit, analyze, process, save and print 8-bit, 16-bit and 32-bit images. It can read many image formats including TIFF, GIF, JPEG, BMP, DICOM, FITS and “raw”. It supports “stacks”, a series of images that share a single window.

It can calculate area and pixel value statistics of user-defined selections. It can measure distances and angles. It can create density histograms and line profile plots. It supports standard image processing functions such as contrast manipulation, sharpening, smoothing, edge detection and median filtering.

Spatial calibration is available to provide real world dimensional measurements in units such as millimeters. Density or gray scale calibration is also available.

Features include:

• Fast in operation.
• 8-bit grayscale or indexed color, 16-bit unsigned integer, 32-bit floating-point and RGB color
• Automate tasks and create custom tools using macros. Generate macro code using the command recorder and debug it using the macro debugger. More than 300 macros are available on the ImageJ Web site.
• Tools are provided for zooming (1:32 to 32:1) and scrolling images.
• Open and save all supported data types as TIFF (uncompressed) or as raw data. Open and save GIF, JPEG, BMP, PNG, PGM, FITS and ASCII. Open DICOM. Open TIFFs, GIFs, JPEGs, DICOMs and raw data using a URL. Open and save many other formats using plugins.
• Create rectangular, elliptical or irregular area selections. Create line and point selections. Edit selections and automatically create them using the wand tool. Draw, fill, clear, filter or measure selections. Save selections and transfer them to other images.
• Enhance images – Supports standard image processing functions such as logical and arithmetical operations between images, contrast manipulation, convolution, Fourier analysis, sharpening, smoothing, edge detection and median filtering on both 8-bit grayscale and RGB color images. Interactively adjust brightness and contrast of 8, 16 and 32-bit images.
• Perform geometric transformations such as scaling, rotation and flips.
• Crop, scale, resize and rotate. Flip vertically or horizontally.
• Analysis: Measure area, mean, standard deviation, min and max of selection or entire image. Measure lengths and angles. Use real world measurement units such as millimeters. Calibrate using density standards. Generate histograms and profile plots.
• Edit images.
• Color processing.
• Supports image stacks, a series of images that share a single window.
• Multithreaded.
• Plugins to extend functionality.

Website: imagej.net/ij
Support: Documentation, GitHub Code Repository
Developer: Wayne Rasband
License: No license – public domain

ImageJ is written in Java. Learn Java with our recommended free books and free tutorials.

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