4 ms·

Thanks, FastBit looks quite interesting, but the site is so... academic. So much great research is lurking behind "unassuming" web presences. 'Someone should do

by jmah 15y ago

Thanks, FastBit looks quite interesting, but the site is so... academic. So much great research is lurking behind "unassuming" web presences. 'Someone should do something!' https://sdm.lbl.gov/fastbit/ https://sdm.lbl.gov/fastbit/

siganakis 15y ago
It is also worth noting that some of the technology underpinning FastBit is actually patented (the Word Aligned Hybrid method of run length encoding). http://www.freepatentsonline.com/6831575.html http://www.freepatentsonline.com/6831575.html Basically the patent covers the method of run length encoding. Each bitmap is stored as an array of words (32/64 bit ints), with each word being either a "fill word" telling it that the next x words are all 0/1 or a "literal word" containing an actual sequence of 0's and 1's. Its a pretty sorry state of affairs when core, relatively simple data structures are patentable. Imagine if someone had patented the linked-list or binary search tree! Interestingly, FastBit (which uses this IP) is released under the LGPL [Edit: improved clarity]
- AlisdairO 15y ago
  It is frustrating :-(. The earlier (and inferior) byte aligned bitmap compression is patent free, as I recall.
- justincormack 15y ago
  That, er, seems obvious, and I would have thought has prior art...
  - jorgeleo 15y ago
    In the US prios art does not count anymore. There are papers since the 60s about bitmap indices, but now is first to file not first to invent... Politics screw us up again
    - mcherm 15y ago
      Legally, prior art still invalidates a patent. But that only matters if you can afford to litigate.
      - jorgeleo 15y ago
        Link to proof this? I am very curious...
- nivertech 15y ago
  This is so obvious, that I'm sure there is a prior art. I used similar RLE encoding for image compression tens of years ago.