Re: [mkgmap-dev] [mkgmap-svn] Commit r572: MDR16 is some kind of codebook.

2021-12-18 Thread Gerd Petermann
Hi Ticker, maybe the table allows to decode the strings faster or someone very unexperienced invented the code or it's intended obfuscation or Garmin took an algo that was meant for something else and what we see is partly ignored. Gerd Von: mkgmap-dev

Re: [mkgmap-dev] [mkgmap-svn] Commit r572: MDR16 is some kind of codebook.

2021-12-18 Thread Ticker Berkin
Hi Gerd I'm amazed at how they've made something that could be simple and expressed with a few byte of control, around 140 bits for tree structure and 80 or so bytes of characters so big and complex! Maybe the few (5) layers closest to the root somehow hard coded. Where a node has a sub-tree on

Re: [mkgmap-dev] [mkgmap-svn] Commit r572: MDR16 is some kind of codebook.

2021-12-18 Thread Gerd Petermann
Hi Ticker, sorry, my last post turned out to be wrong. The byte at offset 2 must have a different meaning. The previously posted mdr16 for benelux has a value of 2 but 4 bytes for the "struct", while the hungary map has a value of 2 and only 3 bytes for struct. Maybe the value for 3 / 4 can be