In computer
software
Software is a set of computer programs and associated software documentation, documentation and data (computing), data. This is in contrast to Computer hardware, hardware, from which the system is built and which actually performs the work.
...
, Grok is a
library
A library is a collection of materials, books or media that are accessible for use and not just for display purposes. A library provides physical (hard copies) or digital access (soft copies) materials, and may be a physical location or a vi ...
to encode and decode images in the
JPEG 2000
JPEG 2000 (JP2) is an image compression standard and coding system. It was developed from 1997 to 2000 by a Joint Photographic Experts Group committee chaired by Touradj Ebrahimi (later the JPEG president), with the intention of superseding th ...
format. It fully implements Part 1 of the ISO/IEC 15444-1
technical standard
A technical standard is an established norm or requirement for a repeatable technical task which is applied to a common and repeated use of rules, conditions, guidelines or characteristics for products or related processes and production methods, ...
. It is designed for stability, high performance, and low memory usage. Grok is
free and open-source software
Free and open-source software (FOSS) is a term used to refer to groups of software consisting of both free software and open-source software where anyone is freely licensed to use, copy, study, and change the software in any way, and the source ...
released under the
GNU Affero General Public License
The GNU Affero General Public License (GNU AGPL) is a free, copyleft license published by the Free Software Foundation in November 2007, and based on the GNU General Public License, version 3 and the Affero General Public License.
The Free Sof ...
(AGPL) version 3.
Features
# High performance - grk_decompress is currently over 1/2 the speed of Kakadu, one of the leading commercial JPEG 2000 libraries
# Fast sub-tile decode
# Supports decoding to stdout for png, jpeg, bmp, pnm, and raw output formats
# Supports TLM code stream marker for fast single-tile and sub-tile decoding of large tiled images
# Supports PLT code stream marker for fast sub-tile decoding of large single-tile images
# Full support for ICC profiles and other meta-data such as XML, IPTC and XMP
# Supports new Part 15 of the standard, aka High Throughput JPEG 2000, which promises up to a 10x speed up over the original Part 1 of the JPEG 2000 standard
Integration
Grok has been integrated into a number of other open source projects, including:
Cantaloupeimage server
IIPSrvimage server
Horosmedical image viewer
References
Further reading
* "JPEG2000 Image Compression Fundamentals, Standards and Practice", by David S. Taubman, Michael W. Marcellin.
*
*
External links
*
User guide
See also
*
OpenJPEG
OpenJPEG is an open-source library to encode and decode JPEG 2000 images. As of version 2.1 released in April 2014, it is officially conformant with the JPEG 2000 Part-1 standard. It was subsequently adopted by ImageMagick instead of JasPer in 6.8. ...
*
Kakadu
JPEG
C++ libraries
Graphics libraries
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