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JPEG 2000 (Joint Photographic Experts Group 2000, .jp2, .j2c)

JPEG 2000 is a wavelet-based image compression standard. It was created by the Joint Photographic Experts Group committee in the year 2000 with the intention of superseding their original discrete cosine transform-based JPEG standard (created about 1991). The standardized filename extension is .jp2 for ISO/IEC 15444-1 conforming files and .jpx for the extended part-2 specifications, published as ISO/IEC 15444-2, while the MIME type is image/jp2.

JPEG 2000 requires far greater decompression time than JPEG and allows more sophisticated progressive downloads, yet averages similar compression rates. JPEG 2000 becomes increasingly blurred with higher compression ratios rather than generating JPEG's "blocking and ringing" artifacts, complicating direct comparison of their respective compression rates.

Part of JPEG 2000 has been published as an ISO standard, ISO/IEC 15444-1:2000. As of 2007, JPEG 2000 is not widely supported in web browsers, and hence is not generally used on the World Wide Web. Even though provisions have been made to integrate all kinds of external meta-data, there is currently no accepted way to embed Exif data (although a JPEG 2000 "JpgTiffExif->JP2" UUID box to store EXIF information has been proposed, and is implemented by ExifTool version 6.92 or later).

Motion JPEG 2000

Motion JPEG 2000 (often referenced as MJ2 or MJP2) is the leading digital film standard currently supported by Digital Cinema Initiatives (a consortium of most major studios and vendors) for the storage, distribution and exhibition of motion pictures. It also is under consideration as a digital archival format by the Library of Congress. It is an open ISO standard and an advanced update to MJPEG (or MJ), which was based on the legacy JPEG format. Unlike common video codecs, such as MPEG-4, WMV, and DivX, MJ2 does not employ temporal or inter-frame compression. Instead, each frame is an independent entity encoded by either a lossy or lossless variant of JPEG 2000. Its physical structure does not depend on time ordering, but it does employ a separate profile to complement the data. For audio, it supports LPCM encoding, as well as various MPEG-4 variants, as "raw" or complement data.

Source: en.wikipedia.org