Astronomy and Astrophysics – Astrophysics – Instrumentation and Methods for Astrophysics
Scientific paper
2011-08-19
Astron. Astrophys. 531 (2011) A98
Astronomy and Astrophysics
Astrophysics
Instrumentation and Methods for Astrophysics
13 pages, 8 figures, accepted for publication by A&A; We make our SZIP program that implements these compression algorithms av
Scientific paper
10.1051/0004-6361/201015728
Large data-sets defined on the sphere arise in many fields. In particular, recent and forthcoming observations of the anisotropies of the cosmic microwave background (CMB) made on the celestial sphere contain approximately three and fifty mega-pixels respectively. The compression of such data is therefore becoming increasingly important. We develop algorithms to compress data defined on the sphere. A Haar wavelet transform on the sphere is used as an energy compression stage to reduce the entropy of the data, followed by Huffman and run-length encoding stages. Lossless and lossy compression algorithms are developed. We evaluate compression performance on simulated CMB data, Earth topography data and environmental illumination maps used in computer graphics. The CMB data can be compressed to approximately 40% of its original size for essentially no loss to the cosmological information content of the data, and to approximately 20% if a small cosmological information loss is tolerated. For the topographic and illumination data compression ratios of approximately 40:1 can be achieved when a small degradation in quality is allowed. We make our SZIP program that implements these compression algorithms available publicly.
Eyers D. M.
McEwen Don J.
Wiaux Yves
No associations
LandOfFree
Data compression on the sphere does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Data compression on the sphere, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Data compression on the sphere will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-107950