fix: stabilize native release builds across platforms

2026-03-04 15:44:28 +09:00
parent 17d44baa2f
commit 7b454e14ed
43 changed files with 10193 additions and 3 deletions
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+# Zune-JPEG
+
+A fast, correct and safe jpeg decoder in pure Rust.
+
+## Usage
+
+The library provides a simple-to-use API for jpeg decoding
+and an ability to add options to influence decoding.
+
+### Example
+
+```Rust
+// Import the library
+use zune_jpeg::JpegDecoder;
+use std::fs::read;
+
+fn main()->Result<(),DecoderErrors> {
+    // load some jpeg data
+    let data = read("cat.jpg").unwrap();
+    // create a decoder
+    let mut decoder = JpegDecoder::new(&data);
+    // decode the file
+    let pixels = decoder.decode()?;
+}
+```
+
+The decoder supports more manipulations via `DecoderOptions`,
+see additional documentation in the library.
+
+## Goals
+
+The implementation aims to have the following goals achieved,
+in order of importance
+
+1. Safety - Do not segfault on errors or invalid input. Panics are okay, but
+   should be fixed when reported. `unsafe` is only used for SIMD intrinsics,
+   and can be turned off entirely both at compile time and at runtime.
+2. Speed - Get the data as quickly as possible, which means
+    1. Platform intrinsics code where justifiable
+    2. Carefully written platform independent code that allows the
+       compiler to vectorize it.
+    3. Regression tests.
+    4. Watch the memory usage of the program
+3. Usability - Provide utility functions like different color conversions functions.
+
+## Non-Goals
+
+- Bit identical results with libjpeg/libjpeg-turbo will never be an aim of this library.
+  Jpeg is a lossy format with very few parts specified by the standard
+  (i.e it doesn't give a reference upsampling and color conversion algorithm)
+
+## Features
+
+- [x] A Pretty fast 8*8 integer IDCT.
+- [x] Fast Huffman Decoding
+- [x] Fast color convert functions.
+- [x] Support for extended colorspaces like GrayScale and RGBA
+- [X] Single-threaded decoding.
+- [X] Support for four component JPEGs, and esoteric color schemes like CYMK
+- [X] Support for `no_std`
+- [X] BGR/BGRA decoding support.
+
+## Crate Features
+
+| feature | on  | Capabilities                                                                                |
+|---------|-----|---------------------------------------------------------------------------------------------|
+| `x86`   | yes | Enables `x86` specific instructions, specifically `avx` and `sse` for accelerated decoding. |
+| `std`   | yes | Enable linking to the `std` crate                                                           |
+
+Note that the `x86` features are automatically disabled on platforms that aren't x86 during compile
+time hence there is no need to disable them explicitly if you are targeting such a platform.
+
+## Using in a `no_std` environment
+
+The crate can be used in a `no_std` environment with the `alloc` feature.
+
+But one is required to link to a working allocator for whatever environment the decoder
+will be running on
+
+## Debug vs release
+
+The decoder heavily relies on platform specific intrinsics, namely AVX2 and SSE to gain speed-ups in decoding,
+but they [perform poorly](https://godbolt.org/z/vPq57z13b) in debug builds. To get reasonable performance even
+when compiling your program in debug mode, add this to your `Cargo.toml`:
+
+```toml
+# `zune-jpeg` package will be always built with optimizations
+[profile.dev.package.zune-jpeg]
+opt-level = 3
+```
+
+## Benchmarks
+
+The library tries to be at fast as [libjpeg-turbo] while being as safe as possible.
+Platform specific intrinsics help get speed up intensive operations ensuring we can almost
+match [libjpeg-turbo] speeds but speeds are always +- 10 ms of this library.
+
+For more up-to-date benchmarks, see the online repo with
+benchmarks [here](https://etemesi254.github.io/assets/criterion/report/index.html)
+
+
+[libjpeg-turbo]:https://github.com/libjpeg-turbo/libjpeg-turbo/
+
+[image-rs/jpeg-decoder]:https://github.com/image-rs/jpeg-decoder/tree/master/src