Best Compression Methods for 'Specific' Games. Q&A

[Cesar82]

Originally Posted by hydefromt70s

I did some more tests today on "The Medium". My goal was to find the most efficient algorithm for test file which contains Zlib streams. The winner is XT xZlib (old xtool) - managed to inflate file from 968MB to 1250MB and with srep and lzma compression, final size went down to 283MB. That meets my expectation.

Now is the part where I don't understand things. If file contains Zlib streams (I did check in "Drop and Scan for Zlib" app so I'm sure of that) I was betting on XT2020 Zlib/reflate/preflate that one of them will be the most efficient pre-compressor and they didn't work at all! I thought that new version of xtool 2020 will be better than old one? What I don't understand here is why XT xZlib worked and XT2020 Zlib didn't? Are they not the same algorithms to deal with deflated streams?

Would highly appreciate if someone could explain this to me.

Maybe it's because old XTool includes reflate automatically if the reflate libraries (raw2hif_dll.dll and hif2raw_dll.dll) are next to xtool.exe
If they were with XTool, try removing raw2hif_dll.dll and hif2raw_dll.dll from the old Xtool, or use XTool 2020 with "zlib+reflate" methods to get an equivalent comparison.
If I reported wrong, please correct me.


Edit:
I did some tests:
sample: pakchunk0-WindowsNoEditor.pak (from game version GOG)
The results were practically the same.

XTool v0.3.9 (2020) (only zlibwapi.dll next to XTool.exe)
packcmd   = XTool.exe precomp -mzlib -c64mb -t100p --dbase - - <stdin> <stdout>
unpackcmd = XTool.exe decode -t100p - - <stdin> <stdout>

pack:
Compressed 1 file, 1,015,774,515 => 1,303,484,741 bytes. Ratio 128.32%
Compression time: cpu 1.03 sec/real 14.51 sec = 7%. Speed 70.00 mB/s

unpack:
Extracted 1 file, 1,303,484,741 => 1,015,774,515 bytes. Ratio 128.32%
Extraction time: cpu 1.84 sec/real 5.74 sec = 32%. Speed 177.02 mB/s

XTool v0.1.2 (OLD) (only zlibwapi.dll next to XTool.exe)
packcmd   = XTool.exe e:precomp:t75p,c128m:zlib - - <stdin> <stdout>
unpackcmd = XTool.exe d:precomp:t90p - - <stdin> <stdout>

pack:
Compressed 1 file, 1,015,774,515 => 1,303,386,164 bytes. Ratio 128.31%
Compression time: cpu 1.05 sec/real 28.62 sec = 4%. Speed 35.50 mB/s

unpack:
Extracted 1 file, 1,303,386,164 => 1,015,774,515 bytes. Ratio 128.31%
Extraction time: cpu 1.50 sec/real 5.83 sec = 26%. Speed 174.33 mB/s