[CDG5] Random questions

[Max Poliakovski]

>From my understanding, the bit-mapped compression allows for a bigger
alphabet than a 256 words table can hold. This means a greater flexibility
but a worse compression ratio. Instead of replacing each word with a table
index (which ideally yields a 2:1 compression), we add an extra byte for
each group of eight words indicating if a particular word is coded "as is"
(plain text) or as table index. The compression ratio in this case is left
as an exercise to the reader.

Non-bitmapped compression assumes that all words will be in the lookup
table that, in turn, seems to be pretty small for large resources. This
therefore makes me think that the bitmapped compression is used more
frequently than the non-bitmapped one.

My code doesn't currently support automatic mode/table switching but relies
on these parameters being supplied by user. Because we're speaking about
small changes, recompressing a particular resource under control of the
original parameters looks like the easiest solution...


Am Mi., 12. Dez. 2018 um 00:25 Uhr schrieb Elliot Nunn <
elliotnunn at fastmail.com>:

> Neat!
>
> What is the significance of isBitMapped?
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