There is only one file type that uses the .LJP extension:
Lossless JPEG Image
JPEG image used by Nero MediaHub, a multimedia file browsing and organizing program that is part of the Nero Multimedia Suite; stores a .JPG image in a lossless format, which is uncommon for JPEG images, but nonetheless is supported by the JPEG standard.
The lossless JPEG format is not supported by many image viewers.
Updated: December 7, 2010