Opening J2K files

Did your computer fail to open a J2K file? We explain what J2K files are and recommend software that we know can open or convert your J2K files.

What is a J2K file?

The .j2k file extension is a raster bitmap image file type that is used by Joint Photographic Experts Group (JPEG) 2000 files. The JPEG 2000 format uses wavelet-based image compression instead of the DCT (Discrete- Cosine- Transform) compression and stores metadata. The metadata or the description information of the .j2k file is coded in XML as compared to the standard .jpeg or .jpg format that are basically formatted with EXIF data.

JPEG 2000 files are saved with a .j2k extension but typically, they can also be in either JP2 or JPX extension. For Windows, JPEG 2000 files can be open using the most popular image viewers and editors like the ones pioneered by Adobe and Corel. Though they are still not as common as standard JPG files, J2K files can support 16-bit color, alpha transparency, and lossless compression.

For Mac users, they can view and/ or edit the .j2k files by utilizing the following software: ToyViewer, Lemkesoft GraphicConverter, Adobe Photoshop CC 2015, Adobe Photoshop Elements 14, and Apple QuickTime Player.

Try a universal file viewer

In addition to the products listed above, I would suggest that you try a universal file viewer like Free File Viewer. It can open over 200 different types of files - and very likely yours too! Download Free File Viewer.

By Prof. Jones (The File Expert)

Chief Content Editor and File Expert

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