JP2
From The Glossary of Digital Photography
The filename extension for JPEG 2000, a compressed file format based on wavelets instead of the discrete cosine transforms technique used for JPEG. See also JPEG; JPEG 2000

ONLINE GLOSSARY OF DIGITAL PHOTOGRAPY
The filename extension for JPEG 2000, a compressed file format based on wavelets instead of the discrete cosine transforms technique used for JPEG. See also JPEG; JPEG 2000