Hacking ROM Hack LZ77 and Huffman Compression tools

TwoSpikedHands

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Does anyone happen to know of any tools that can compress data in a 1-1 ratio with the GBA? So far I have been using these tools by CUE (which are AMAZING) - but if I decompress data then recompress it (without modifying it) the data somehow is not exactly the same

Here's a bit of context:

Below on the left is some data that was decompressed using ONLY huffman algo
Below on the right is data that was decompressed with both huffman, then lz77, unmodified, then recompressed using lz77

COMPARISON.png



To my knowledge this should be the exact same data since the decompressed data using the same huffman and lz77 compression tools looks exactly the same as it does in game:

COMPARISON2.png


There's likely something I'm overlooking at the moment, does anyone happen to know what I'm missing? I know for a fact that the decompression tools are working perfectly, it just appears that when I try to re-compress that same exact data is when I start to get issues... I don't know a whole lot about what I'm doing but I've tried quite a few things, including compressing it back with each and every single parameter possible within the command - but nothing is able to replicate the same exact data back. It's always SIMILAR, but the re-compressed data is never the same, and is typically longer than the original huffman decompressed data

A link to the tool I am using to compress/decompress is here:
https://www.romhacking.net/utilities/826/
 
Last edited by TwoSpikedHands,

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    I really would like to make a hack that I would enjoy playing, and maybe other people would too. swapping to the EU version would also mean my US friends could not legally play it
  • TwoSpikedHands @ TwoSpikedHands:
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    I appreciate the insight!
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