JP2

File Format
Name	JP2
Ontology	Electronic File Formats Graphics JPEG 2000 JP2
Extension(s)	.jp2
MIME Type(s)	image/jp2
LoCFDD	fdd000143, others
PRONOM	x-fmt/392

JP2 is the baseline image file format defined by the JPEG 2000 standard. It encapsulates a JPEG 2000 codestream.

Identifiers

Format	PRONOM	LoCFDD
JP2	x-fmt/392	fdd000143
JP2, Lossless		fdd000167
JP2, Lossy		fdd000168
JP2, Profile 0		fdd000195
JP2, Profile 1		fdd000197
JP2, Profile 3		fdd000212
JP2, Profile 4		fdd000214
JP2, BIIF Profile		fdd000169
JP2, NDNP Profile		fdd000193

Identification

JP2 files begin with bytes 00 00 00 0c 6a 50 20 20 0d 0a 87 0a ?? ?? ?? ?? 66 74 79 70 6a 70 32 20.

Note that some Adobe applications (most notably Adobe Photoshop) produce JPX (JPEG 2000 Part 2) images that erroneously use the above byte sequence, which makes them (superficially) indistinguishable from JP2 images.

Specifications

• ISO/IEC 15444-1 Annex I: JP2 file format syntax
• ITU-T Rec. T.800 (not free to download)
• JPEG 2000 Committee Drafts → fcd15444-1.pdf
• Updated ICC profile support, bit depth and resolution clarifications - 2013 amendment to the filespec that extends support of ICC profiles and clarifies use of resolution fields in JP2
• Updated ICC profile support, bit depth and resolution clarifications - August 2011 draft of above amendment (freely available)
• BIIF Profile for JPEG 2000
• JPEG 2000 Profile for the National Digital Newspaper Program (NDNP Profile)

Software

See also JPEG 2000.

• Konvertor
• Jpylyzer: JP2 validator and property extractor

Note also that the jpylyzer manual includes a detailed breakdown of the JP2 format structure.

• Compute compression ratio for all JP2s in directory tree (shell script)
• RAIS Image Server: An IIIF-compliant, 100% open source tile server for JP2 images

Sample files

• Jp2k test corpus - annotated set of images, primarily intended to demonstrate specific preservation risks

• Jpylyzer test files - annotated set of images, primarily intended as test dataset in support of jpylyzer development. Includes many (deliberately) corrupted files.

• JPEG 2000 sample images - sample files for each format in the JPEG 2000 format family

• openjpeg-data - all files required to run the openjpeg test suite, includes many badly corrupted files

Related formats

• GeoJP2 is an extension of the JP2 format which allows one to include geospatial metadata in georeferenced JP2 images.

Links

• Wikipedia:JPEG 2000
• Is JPEG-2000 a Preservation Risk?
• JP2 entries in OPF File Format Risk Registry - describes some issues with (older versions of) the format spec and issues with specific implementations
• Six ways to decode a lossy JP2
• Example JP2 profiles (types of JP2s used by different institutions)
• Online demonstrator- shows quality differences between similarly-sized images in JPEG, JP2, WebP and BPG formats
• JP2 Format Preservation Assessment (British Library)
• Catching and potentially reporting apparent compressed bitstream errors
• JPEG2000 Is Slow … Or Is It?