There is minor update to LZO, a portable lossless data compression library written in ANSI C. It offers pretty fast compression and very fast decompression.

This update makes some minor changes to a major upgrade released on May 30th, 2005. For a complete changelog, click here.

NewsForge is running an article on the LZW mess created by the Unisys patent and the scene almost an year after the patent expired.

A comp.compression post by someone called Goldy (Kyle) brings foward an interesting method for publically demonstrating any new compression algorithms without risking reverse engineering.

The previously accepted method used two physically seperate computers with compression done on one, decompression done on other and data tranferred b/w the two using media like floppy/cd. It required the inventor and evaluator to be present in same physical room, the computers to be provided by evaluator (to rule out previous tampering) and then be destroyed or given to inventor (to rule out possibility of reverse engineering).

New method is much more efficient and can work online, and is thus better suited for public demonstration.

Here it is…

Step 1) Allow the public to download a “decompressor” program. The decompressor should not make any network connections of any kind.

Step 2) Allow the public to upload a file to a server to be compressed.

Step 3) The server compresses the file and generates a compressed file on server which can be downloaded and given to decompressor program. (All submitted files for testing can be made accessible to the public on this web page, so everyone can see what everyone else has submitted to be tested, and check it themselves, but this part is not necessary)

Step 4) Run the decompressor program on the downloaded compressed file get the output file. Preferrably on a different computer which has no traces of original file.

Step 5) Transfer both files (Original and the one generated by decompressor) on same computer and compare the two files with DIFF or something similar to see if they match.

As the compressor never leaves the hands of original inventor, he can relax that it cant be reverse engineered

Although this method was presented in context of randam data compressors (uh!) it can ofcourse be used for evaluating or demonstrating any research breakthrough in data-compression.

Update: As many compression algorithms can be reverse engineered (atleast to a large extent) even if only decompressor is available, this method is restricted to only those cases where inventor feels that he can safely release the decompressor.

You can check this comp.compression thread for details on a bug in David’s VH2 coder which is now fixed.

Update: More information here.

Even though there is too much buzz around MPEG-4, EE Times has a news article on why MPEG-2 might still continue to grow till 2009.

In a press release, The Open Geospatial Consortium Inc. (OGC) invites public comment on a candidate specification that will soon be presented for approval by OGC members as an OpenGIS(R) Implementation Specification. The OGC Document, “GML in JPEG 2000 for Geographic Imagery (GMLJP2) Implementation Specification,” is available for downloading from https://portal.opengeospatial.org/files/?artifact_id=11418. Comments can be submitted to gmljp2-rfc@opengeospatial.org for a thirty-day period ending July 27; Comments received will be consolidated and reviewed by OGC members for incorporation into the document.

The Geography Markup Language (GML) is an XML grammar for the encoding of geographic information including geographic features, coverages, observations, topology, geometry, coordinate reference systems, units of measure, time, and value objects. JPEG 2000 is a wavelet based encoding for imagery that provides the ability to include XML data for description of the image within the JPEG 2000 data file. The “GML in JPEG 2000 for Geographic Imagery (GMLJP2) Implementation Specification” defines the OGC standard method of using GML within JPEG 2000 images for geographic imagery.

OGC is an international industry consortium of more than 280 companies, government agencies and universities participating in a consensus process to develop publicly available interface specifications. OpenGIS(R) Specifications support interoperable solutions that “geo-enable” the Web, wireless and location-based services, and mainstream IT. The specifications empower technology developers to make complex spatial information and services accessible and useful with all kinds of applications. Visit the OGC website at http://www.opengeospatial.org.

The folks at CMP publish lots of well known trade magazines, such as EE Times. I get promotional mailings from them, and this one is kind of interesting. It’s offering a free net seminar on video coding, with the following blurb:

Not all codecs are created equal in terms of the tradeoffs they make between compression rates, encode/decode processing requirements and key system factors such as latency. This Net Seminar will provide a brief introduction to how video compression is achieved and insight into why advanced video codecs and specific profiles within these codecs are better suited for certain applications. Codecs discussed will include H.264 (aka MPEG-4 AVC), VC-1 (aka Windows Media Video 9), MPEG, and others.

Discussion topics will include: Microsoft’s VC1 versus H.264 — is there any difference from a DSP system point of view? Why does encoding require so much more processing power than decoding? How do resolution and frame rates factor in? Why are some codecs better suited for certain applications? What are the advantages of alternative video codecs from DivX, On2, and Real Networks. Can DSPs handle any codec, or do some require more computing power than DSP can provide? How does an engineer obtain codec software to work with a given processor?

I think TI is sponsoring the event, which means they don’t really care what codec you use as long as you are using a TI DSP to do the work. If you’re interesting in jumping in, you might be able to register via this friends and colleagues URL that came with the email.

This article illustrates how difficult archiving is vs. just ‘backing up’ data. From the 38 million email messages created by the Clinton administration to proprietary data sets created by NASA, the National Archives and Records Administration is expecting to have as much a 347 petabytes to deal with by 2022. Are we destined for a “digital dark age”?”

This is the text from a slashdot post. Surly worth reading.

MP3 files are very sensitive. Just a single modified byte can make the whole file unreadable for several MP3 player. Thus it’s not hard that an accident or bug in a mp3 editor corrupts a file. With MP3 Repair Tool you might be able to listen to that song again.

I havent tried this tool myself but the sales-pitch sure is impressive. Get more information and a download link here.

Intel now runs the Intel Science Talent Search, the high school science competition that has a long history in the US. Lots of illustrious scientists have participated in this program over the years, and the roster includes winners of all sorts of other prizes. One of the finalists this year was Sisi Monica Chen from Duluth GA (yes, that Duluth GA!) Ms. Chen’s project was an analysis of the least number of 1’s needed to express any integer. I’d love to see a copy of the paper online, but all we have right now is this PDF press release.