nsmbw-compress

Tool for encoding and decoding various different compression formats supported by New Super Mario Bros. Wii and other games using the same libraries.

Here's a list of the supported formats:

Format	Extension	Description	Encode	Decode	Known Uses
lz	.LZ	Lempel-Ziv	Yes	Yes	New Super Mario Bros. Wii
huff	.HUFF	Huffman	Yes	Yes
rl	.RL	Run-length	Yes	Yes
lh	.LH	LZ + Huffman	Yes	Yes	Mario Sports Mix
lrc	.LRC	LZ + Range Coder	No	Yes
filter-diff	.DIFF	Differential Filter	Yes	Yes
szs	.szs	SZS/Yaz0	Yes	Yes	Many first-party Nintendo games
ash	.ash	ASH0 (LZ + Huffman)	Yes	Yes	Wii Menu
asr	.asr	ASR0 (LZ + Range Coder)	Yes	Yes	Super Mario Advance 4

Usage

Usage: nsmbw-compress [options] <input> [-o output]
Options:
  -h, --help      Show this help message and exit
  -o, --output    <path> Specify the output file name
  -t, --type      <type> Specify the compression type (see supported types below)
  -x, --uncomp    Decompress the input file instead of compressing
  -l, --lz-mode   <0, 1*, auto> Specify the LZ compression mode
  -b, --huff-size <4, 8, auto*> Specify the bit size for Huffman compression
  -r, --asr-mode  <0, 1, auto*> Specify the mode for ASR compression
  -d, --diff-size <8*, 16> Specify the element size for filter-diff encoding
      --test      Run internal tests and exit
  -v, --verbose   Print verbose output
Supported types for compression:
  lz huff rl lh diff szs ash asr 
Supported types for decompression:
  lz huff rl lh lrc diff szs ash asr

Comparisons

Here is a comparison between compressed sizes of nsmbw-compress, the internal ntcompress tool used by Nintendo, and Cue's Nintendo DS/GBA Compressors for LZ specifically.

The file used here is Kinopio.arc from New Super Mario Bros. Wii, which has an uncompressed size of 381536 bytes. The following table compares the size in bytes of the output of each format:

Format	nsmbw-compress	ntcompress	Cue (lzx)
lz	205415	207455 (+2040)	207177 (+1762)
lz (old-lz11)	212769	214638 (+1869)	N/A
huff (4-bit)	345836	345836 (+0)	N/A
huff (8-bit)	316208	316208 (+0)	N/A
rl	345406	345406 (+0)	N/A
lh	158713	166692 (+7979)	N/A

In the single-file test, the output of nsmbw-compress is either identical to or smaller than the output of ntcompress in every supported format, with the greatest savings exhibited in LH.

The following table compares the szs format specifically, which was not supported by ntcompress, between nsmbw-compress and Wiimm's SZS Tool (wszst).

Format	nsmbw-compress	wszst --compr 10	wszst --compr 120
szs	205480	205620 (+140)	205344 (-136)

Wiimm's tool overtakes nsmbw-compress by a fair margin when using the time-consuming backtracking option (specifically --compr 120 in this test). I don't intend to create my own full backtracking alternative, so wszst is still preferred if you need the best possible compression.

Building

Run the following in the repository root:

mkdir build
cd build
cmake ..
cmake --build .

Or simply run your preferred compiler with *.c in the repository root.