HP Labs LOCO-I/JPEG-LS Home Page

JPEG-LS is the new lossless/near-lossless compression standard for continuous-tone images, ISO-14495-1/ITU-T.87. The standard is based on the LOCO-I algorithm (LOw COmplexity LOssless COmpression for Images) developed at Hewlett-Packard Laboratories.

References:

• M. Weinberger, G. Seroussi, G. Sapiro, "The LOCO-I Lossless Image Compression Algorithm: Principles and Standardization into JPEG-LS", Hewlett-Packard Laboratories Technical Report No. HPL-98-193R1, November 1998, revised October 1999.  IEEE Trans. Image Processing, Vol. 9, August 2000, pp.1309-1324.  PDF   Postscript 
• M. Weinberger, G. Seroussi, G. Sapiro, "LOCO-I: A Low Complexity, Context-Based, Lossless Image Compression Algorithm," Proc. IEEE Data Compression Conference, Snowbird, Utah, March-April 1996.

The term "near-lossless compression" refers to a lossy algorithm for which each reconstructed image sample differs from the corresponding original image sample by not more than a pre-specified value, the (usually small) "loss." Lossless compression corresponds to loss=0.

An earlier version of the standard draft can be found at the official JPEG Web site.

• Comparisons with the old lossless JPEG (Huffman and arithmetic), CALIC, FELICS, and PNG can be found in the full paper.

• JPEG-LS Public Domain Code  (JPEG-LS source code).
• LOCO on Mars!

For more details, contact loco@hpl.hp.com.

Last Updated: May 13, 2005