Board index » delphi » Re: Delphi version of LZO?

2006-05-26 09:32:30 PM
delphi178
Thx for the links. On Gemac seems to be producing cards for the Windows
platform. Have you personally tried any of them? Are they easy to program
for, in Delphi or C++?
Ray Mond
 

www.ddj.com/dept/cpp/184402606
It's called "Ross Data Compression (RDC)", doesn't mention LZ, but from
the source, it looks like a close LZ77 variant.
Eric
 

compression happens at both ends.
It's used for a DB middleware, as even though our data stream contains
very little "truly" redundant data, there is a lot of redundancy across
records, from batch numbers that share their first numbers to names
where you have variants of the same thing, like in "blue string, red
string, blue rope, red rope", etc.
Most of the time, a fast compressor is enough to cut the amount of data
to a fraction of the uncompressed size.
Eric
 

I'm using delphi's own zlib and I can achieve
compression rates of 30-40MB/sec and
decompression rates of 80-90MB/sec by
using fastest compressible option and
in-memory compress/decompress
(TMemoryStream).. This takes a bit of
memory but serves our purpose to
maximize network throughput..
Juhani Suhonen
"Eric Grange" <XXXX@XXXXX.COM>writes

while being 2-3 times slower (depending on the data being compressed).
You really need to bump up the compression level with ZLib to see a
difference, but then, the speed becomes very different too...
Eric