whisper-cpp-plus-sys

Pinned to whisper.cpp v1.8.3 (fork: rmorse/whisper.cpp, branch: stream-pcm)

Low-level FFI bindings to whisper.cpp for Rust.

This is the foundation crate for whisper-cpp-plus. For a safe, high-level API, use whisper-cpp-plus instead.

Features

Feature	Description
`quantization`	Model quantization support
`cuda`	NVIDIA GPU acceleration (requires CUDA toolkit)
`metal`	Apple Metal acceleration (macOS)
`openblas`	OpenBLAS acceleration (Linux)

Build

The build script (build.rs) compiles whisper.cpp from source via the cmake crate, or links a prebuilt library if available. CMake is invoked automatically — GPU features like CUDA "just work" with the toolkit installed.

Variable	Description
`WHISPER_PREBUILT_PATH`	Path to prebuilt static libs (skips cmake build)
`WHISPER_NO_AVX`	Disable AVX/AVX2 instructions
`CUDA_PATH`	CUDA toolkit root (checked first for `cuda` feature)
`CUDA_HOME`	CUDA toolkit root (fallback)
`CMAKE_*`	Passed through to CMake (e.g. `CMAKE_CUDA_ARCHITECTURES`)

Platform requirements

All: CMake 3.14+
Windows: Visual Studio 2019+ (MSVC)
Linux: GCC 9+ or Clang 11+, build-essential
macOS: Xcode command line tools (Accelerate linked automatically)

Usage

All functions are unsafe. Key rules:

whisper_context must outlive all whisper_state instances
Each thread needs its own whisper_state
Copy strings from result pointers before freeing state
Free states before context

use whisper_cpp_plus_sys::*;
use std::ffi::CString;

unsafe {
    let params = whisper_context_default_params();
    let path = CString::new("model.bin").unwrap();
    let ctx = whisper_init_from_file_with_params(path.as_ptr(), params);
    assert!(!ctx.is_null());

    let state = whisper_init_state(ctx);
    // ... transcribe ...
    whisper_free_state(state);
    whisper_free(ctx);
}

License