PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2014-03-07 INTERCHANGE_FORMAT = ASCII NOTE = "Description file referenced by XRS JP2 PDS labels" END_OBJECT = TEXT END JPEG2000 Standard - XRS count-rate and abundance maps are stored in the JPEG2000 ISO/IEC Part 1 standard [1] format (http://www.jpeg.org/jpeg2000/), which was accepted as a PDS Standard in October 2005 [2]. The JPEG2000 standard offers benefits with distinct advantages for storage of and access to very large images. Advantages include excellent compression performance, multiple resolution levels from a single image data set, progressive decompression quality layers, lossless and lossy compression (XRS advanced products use lossless compression per the PDS Standard). The PDS Standard specifies that a JPEG2000 codestream will be stored in a "JP2" file as described by the JPEG2000 Part 1 standard [1]. This file format encapsulates one or more codestreams plus characterizing metadata in a contiguous sequence of binary data "boxes". The first two boxes of a JP2 file must be Signature and File Type specification boxes that uniquely identify the file as a JP2 file. This must be followed by a JP2 Header box that contains sub-boxes that characterize the Codestream box that follows with information such as the image dimensions, pixel datum precision, compression technique and color space mapping for image display purposes. The JP2 file may also contain additional boxes that contain UUID (universally unique identifier) signatures, URL (uniform resource locator) references, and XML (extended markup language) sequences that can be used as desired by the data provider. Each XRS JP2 product is associated with a PDS label that contains the map projection information and a description of the image that would result from uncompressing the JPEG2000 file. JPEG2000 Codestream - All of the information necessary to successfully decompress JPEG2000 image data are contained in the JPEG2000 Codestream box of the JP2 file. The flexibility of the format, however, allows for significant variability in how the codestream is structured which can have a significant impact on the performance of client software accessing the codestream during rendering operations. The JPEG2000 image coding techniques are sensitive to byte ordering (for multi-byte data) and signedness of the image data. XRS image data are MSB ordered and unsigned. JPEG2000 Software - Part 5 of the JPEG2000 offers reference software implementations of the Part 1 core-coding standard. The JasPer Project provides a C language API and demonstration applications (http://www.ece.uvic.ca/~mdadams/jasper/). JJ2000 (http://jj2000.epfl.ch/) provides pure Java classes. Both of these implementations are employed in two J2K plugins for the Image I/O Tools from Sun Microsystems' Java Advanced imaging (JAI). (http://java.sun.com/javase/6/docs/technotes/guides/imageio/) (http://java.sun.com/javase/technologies/desktop/media/jai/) Dr. David Taubman, one of the principle JPEG2000 standard developers, implemented the Kakadu software. Kakadu offers a full range of application utilities and highly optimized C++ classes (http://www.kakadusoftware.com/). The JP2_Info utility, in the Image_Tools package of the PIRL Java Packages (http://pirlwww.lpl.arizona.edu/software/PIRL_Java_Packages.shtml) provides a detailed report on the contents of a JP2 file. References - 1. JPEG 2000 image coding system: Core coding system, ISO/IEC 15444-1 September 15, 2004 2. Planetary Data System Data Standards Reference, Version 3.7, JPL D-7669, Part 2, March 20, 2006