22 unstable releases (3 breaking)
1.1.0 |
|
---|---|
0.3.7 | Jul 20, 2024 |
0.3.4 | Nov 16, 2023 |
#22 in Games
465KB
2.5K
SLoC
Contains (Windows DLL, 170KB) py/szs.dll, (Windows DLL, 170KB) c#/bindings/szs.dll
szs
Lightweight crate for SZS ("Yaz0") compression/decompression used in the Nintendo GameCube/Wii games. The library provides C, C++, C#, and WIP Python bindings. YAY0 ("SZP") is supported, too.
Rust
The following snippet demonstrates how to compress a file as a SZS format using Rust:
let src_data: Vec<u8> = "Hello, World!".as_bytes().to_vec();
match szs::encode(&src_data, szs::EncodeAlgo::Nintendo) {
Ok(encoded_data) => {
println!("Encoded into {} bytes", encoded_data.len());
}
Err(err) => {
println!("Encoding failed: {}", err);
}
}
And similarly, to decompress:
match szs::decode(&encoded_data) {
Ok(decoded_data) => {
println!("Decoded {} bytes", decoded_data.len());
}
Err(err) => {
println!("Decoding failed: {}", err);
}
}
C# Bindings
The following C# bindings are provided:
public static void Main(string[] args)
{
byte[] data = ...;
szs.CompressionAlgorithm algorithm = szs.CompressionAlgorithm.Nintendo;
try
{
byte[] encodedData = szs.Encode(data, algorithm);
Console.WriteLine($"Encoded {encodedData.Length} bytes.");
}
catch (Exception e)
{
Console.WriteLine("Failed to compress: " + e.Message);
}
}
Warning: szs
has a portion implemented in C, which brings its own security considerations.
Algorithms
Algorithm | Use Case | Desc |
---|---|---|
EncodeAlgo::Nintendo |
Matching decomp projects | This is the Mario Kart Wii compression algorithm reverse-engineered. In practice it's a Boyer-moore-horspool search with a second opinion mechanism. |
EncodeAlgo::Mk8 |
General FAST preset. |
This is the Mario Kart 8 compression algorithm reverse-engineered. In practice it's a sliding Monte Carlo hash table. (Credit @aboood40091, @KillZGaming) |
EncodeAlgo::MkwSp |
MKW-SP | |
EncodeAlgo::CTGP |
CTGP work | CTGP (Reverse engineered. 1:1 matching) |
EncodeAlgo::WorstCaseEncoding |
INSTANT preset. |
Worst case |
EncodeAlgo::Haroohie |
Haroohie (credit @Gericom, adapted from MarioKartToolbox) | |
EncodeAlgo::CTLib |
CTLib (credit @narahiero, adapted from CTLib) | |
EncodeAlgo::LibYaz0 |
ULTRA preset. |
libyaz0 (Based on wszst. credit @aboood40091) |
Generally, the mk8
algorithm gets acceptable compression the fastest. For cases where filesize matters, lib-yaz0
ties wszst ultra
for the smallest filesizes, while being ~25% faster.
Comparison to Other Libraries:
-
- Performance:
EncodeAlgo::LibYaz0
offers superior compression and is approximately 6x faster on reference data compared toyaz0-rs
. - Note:
szs
has a portion implemented in C, which brings its own security considerations.
- Performance:
-
- Performance:
EncodeAlgo::MK8
matches the compression and speed ofoead
. - Size:
szs
is a lightweight few-kilobyte MIT licensed dependency, whileoead
is a larger multi-megabyte GPL licensed package.
- Performance:
-
- Performance:
EncodeAlgo::LibYaz0
provides equivalent compression towszst ultra
but is about 30% faster and not restricted by the GPL license.EncodeAlgo::MK8
outperformswszst fast
in compression and is 4-5 times faster.
- Performance:
Special Feature: Among the libraries listed, only szs
offers comprehensive support for the YAZ0
, YAZ1
, and YAY0
stream formats.
Benchmarks
Large file comparison
NSMBU 8-43 (63.9 MB decompressed)
Method | Time (Avg 3 runs) | Compression Rate | File Size |
---|---|---|---|
worst-case-encoding | 0.03s | 112.50% | 71.90 MB |
mk8 | 1.37s | 29.43% | 18.81 MB |
ct-lib | 3.01s | 29.74% | 19.01 MB |
haroohie | 5.79s | 29.74% | 19.01 MB |
ctgp | 9.23s | 40.91% | 26.14 MB |
lib-yaz0 | 16.09s | 29.32% | 18.74 MB |
mkw-sp | 36.77s | 29.74% | 19.01 MB |
mkw | 55.00s | 29.40% | 18.79 MB |
mkw (C++) | 63.34s | 29.40% | 18.79 MB |
Comparison with other libraries: | |||
oead default | 0.61s | 30.09% | 19.23 MB |
oead max level | 0.99s | 29.96% | 19.15 MB |
wszst fast | 1.77s | 35.62% | 22.76 MB |
wszst standard | 11.95s | 29.74% | 19.01 MB |
wszst ultra | 25.06s | 29.32% | 18.74 MB |
* Average of 3 runs; x64 Clang (17.0.6) build tested on an Intel i9-13900KF on Windows 11
Small file comparison
Task: Compress N64 Bowser Castle (Source filesize: 2,574,368)
Method | Time (Avg 3 runs) | Compression Rate | File Size |
---|---|---|---|
worst-case-encoding | 0.00s | 112.50% | 2.76 MB |
mk8 | 0.07s | 56.75% | 1.39 MB |
ct-lib | 0.19s | 57.24% | 1.41 MB |
ctgp | 0.21s | 71.41% | 1.75 MB |
haroohie | 0.31s | 57.23% | 1.41 MB |
lib-yaz0 | 1.09s | 56.65% | 1.39 MB |
mkw-sp | 1.47s | 57.23% | 1.41 MB |
mkw | 3.91s | 56.87% | 1.40 MB |
mkw (C++) | 4.27s | 56.87% | 1.40 MB |
Comparison with other libraries: | |||
oead default | 0.03s | 57.63% | 1.41 MB |
oead max level | 0.05s | 57.52% | 1.41 MB |
wszst (fast) | 0.197s (via shell) | 65.78% | 1.61MB |
wszst (standard) | 0.946 (via shell) | 57.23% | 1.40MB |
wszst (ultra) | 1.418s (via shell) | 56.65% | 1.38MB |
yaz0-rs | 4.88s (via shell) | 56.87% | 1.39MB |
* Average of 3 runs; x64 Clang (17.0.6) build tested on an Intel i9-13900KF on Windows 11
Generally, the mk8
algorithm gets acceptable compression the fastest. For cases where filesize matters, lib-yaz0
ties wszst ultra
for the smallest filesizes, while being ~25% faster.
(Windows) Performance Comparison: Clang vs. MSVC
On Windows, Microsoft's compiler (MSVC) appears to fall behind Clang for most algorithms by a non-trivial margin:
Method | Clang Time (s) | MSVC Time (s) | Performance Uplift (%) |
---|---|---|---|
lib-yaz0 | 15.24 | 19.08 | -25.20% |
mkw | 62.04 | 58.34 | 5.96% |
mkw-sp | 26.73 | 50.01 | -87.09% |
haroohie | 5.84 | 5.85 | -0.17% |
ct-lib | 2.91 | 2.81 | 3.44% |
mk8 | 1.34 | 1.62 | -20.90% |
ctgp | 5.22 | 5.88 | -12.64% |
* Average of 3 runs; x64 MSVC build tested on an Intel i9-13900KF on Windows 11
Average Performance Uplift: -19.51%
Recommendation
Based on the performance results, Clang is generally preferred. To set Clang as the compiler for szs
, run the following command before cargo build
:
SET CXX=clang
Additionally, using a compatible Clang/Rust version will allow for cross-language LTO optimizations.
Example (C Bindings)
#include "szs.h"
// Calculate the upper bound for encoding.
u32 max_size = riiszs_encoded_upper_bound(sizeof(data));
// Allocate a buffer based on the calculated upper bound.
void* encoded_buf = malloc(max_size);
if (!buf) {
fprintf(stderr, "Failed to allocate %u bytes.\n", max_size);
return -1;
}
// Boyer-Moore-horspool variant
u32 algorithm = RII_SZS_ENCODE_ALGO_NINTENDO;
u32 actual_len = 0;
const char* ec = riiszs_encode_algo_fast(encoded_buf, max_size, data, sizeof(data), &actual_len, algorithm);
if (ec != NULL) {
fprintf(stderr, "Failed to compress: %s\n", ec);
riiszs_free_error_message(ec);
return -1;
}
printf("Encoded %u bytes.\n", actual_len);
// Optionally: shrink the dst_data to the actual size.
encoded_buf = realloc(encoded_buf, actual_len);
C++ Wrapper on top of C Bindings
A CMake example is provided, too.
#include `szs.h`
// Boyer-Moore-horspool variant
szs::Algo algorithm = szs::Algo::Nintendo;
auto encoded = szs::encode(data, algorithm);
if (!encoded)
std::println(stderr, "Failed to compress: {}.", encoded.error()); {
return -1;
}
std::vector<u8> szs_data = *encoded;
std::println("Encoded {} bytes.", szs_data.size());
License
This library is published under the MIT license.