Author Topic: Quick update on the state-of-the-art compression using ApLib  (Read 4040 times)

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Offline Urusergi

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Is there a link to the compressor and Z80 decompressor?
https://github.com/emmanuel-marty/apultra/releases
asm/z80 in Source Code (zip)

Offline reidrac

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Offline introspec

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Is aPack quicker than Exomizer? Significantly? Oh, I mean decrunching of course.  :)
If you use my "fast" decompressor from the first post in this thread (or slightly extended version from https://github.com/emmanuel-marty/apultra), you'll have twice the speed of the fastest decompressor for Exomizer.

Offline introspec

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Urusergi
Arnaud

I need relevant decompressor on PC for testing. Is there one?
I do not believe there is one to just compile and go. However, the transformation is trivial:
1. Reverse bytes of the input file.
2. Compress the resulting data using your current compressor.
3. Reverse bytes in your resulting compressed stream and save them as the output.

Offline Urusergi

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I do not believe there is one to just compile and go. However, the transformation is trivial:
1. Reverse bytes of the input file.
2. Compress the resulting data using your current compressor.
3. Reverse bytes in your resulting compressed stream and save them as the output.
I already knew that, but it's more comfortable to have the backward option inside the compressor.
Many years ago I did a program called reverse.exe  ;D

Offline introspec

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I think exomizer is today deprecated (slow compression, slow decompression, ratio similar to APultra)
I think this judgement is a bit harsh. In situations where compression ratio is critical, Exomizer still has something like 1.5% advantage and I already had several projects where this small difference resulted in several K of extra space (which was absolutely crucial for me). At the same time, I agree that once the decompression speed becomes ever so slightly important, ApLib has an edge and is very competitive today.
« Last Edit: 16:30, 13 May 20 by introspec »

Offline introspec

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I already knew that, but it's more comfortable to have the backward option inside the compressor.
Many years ago I did a program called reverse.exe  ;D
I had no doubt you knew; I replied to the author of the optimal compressor, just in case he does not know :)

Offline Urusergi

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I had no doubt you knew; I replied to the author of the optimal compressor, just in case he does not know :)
Ahh! ok  :-[

@Eugene85 In case you know z80 assembler:

https://cngsoft.livejournal.com/268202.html

with _aplib8flag=1
 
« Last Edit: 16:40, 13 May 20 by Urusergi »

Offline roudoudou

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I think this judgement is a bit harsh. In situations where compression ratio is critical, Exomizer still has something like 1.5% advantage and I already had several projects where this small difference resulted in several K of extra space (which was absolutely crucial for me). At the same time, I agree that once the decompression speed becomes ever so slightly important, ApLib has an edge and is very competitive today.
Dont misunderstand me,  i wont remove Exomizer from my tools. But most of the time, i wont even try to crunch with it, until i really need  top notch ultra 1% gain  8)
use RASM, the best assembler ever made :p

I will survive

Offline Eugene85

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Urusergi

Added "backward" option to oapack.

Offline Urusergi

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Urusergi

Added "backward" option to oapack.

Ohhh! thank you very much  :)

Offline introspec

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Please note that the latest release 1.3.1 of Apultra supports both backward compression and external dictionaries, see
https://github.com/emmanuel-marty/apultra/releases



I also updated small and fast decompressors to be a bit smaller and a bit faster, as well as added support for backward decompression. Have fun!

Offline genesis8

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Please note that the latest release 1.3.1 of Apultra supports both backward compression and external dictionaries, see
https://github.com/emmanuel-marty/apultra/releases
Latest release is 1.3.5
 
  • Compress another 10% faster compared to v1.3.4 (the compressed output is unchanged)
  • apultra v1.3.5 is 2X faster than v1.2.1 while compressing better
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