NOTE: This is a port of libspecbleach to WebAssembly/JavaScript, not the original libspecbleach!
NOTE 2: This package is under the GNU GENERAL PUBLIC LICENSE. It is not under the GNU LESSER General Public License. If you want a version under a more permissive license, you will have to negotiate with the authors of FFTW and/or libspecbleach. This is just a port!
libspecbleach.js
Load libspecbleach-<version>.js
. If you're loading from a directory other than
.
, then first create a global variable LibSpecBleach
and set its base
field to the directory you're loading it from. You can also set the nowasm
and/or nosimd
fields of LibSpecBleach
to prevent loading these features.
After loading libspecbleach.js
, LibSpecBleach.LibSpecBleach
is a factory
function that returns a promise that resolves to an instance of the SpecBleach
library.
The result of LibSpecBleach.LibSpecBleach()
can be used exactly like the C
libspecbleach
library. Use specbleach.calloc_f32(size)
to allocate a
Float32Array
in the context of the LibSpecBleach instance; it returns an
array with the pointer (needed for C function calls) and the Float32Array
.
Make sure to use specbleach.free
to free it when you're done. Otherwise, the
library is identical to the original libspecbleach, except (a) functions that
take SpecBleachParameter
s instead have versions suffixed with _js
that
take SpecBleachParameter *
s, and (b) the specbleach_
prefix is removed
from all functions, except for specbleach_free
.
Alternatively, libspecbleach.js has an object oriented API.
See examples/denoise_demo.js
and examples/adenoise_demo.js
for examples of
the C API. See examples/denoise_demo_oo.js
and examples/adenoise_demo_oo.js
for examples of the OO API.
The remainder of this document is the original libspecbleach's README, and is not JavaScript-specific.
libspecbleach
C library for audio noise reduction and other spectral effects
Background
This library is based on the algorithms that were used in noise-repellent. These were extracted into a this standalone library to remove the lv2 dependency. It was design to be extensible and modular. It uses the concept of a spectral processor which itself uses a short time Fourier transform (STFT) to process the audio. There are two initial processors in place, one which uses the adaptive part of noise repellent and one that uses the manual capturing profile based denoising. The library could be extended with more spectral processors using any STFT-based algorithm such as de-crackle, de-click and other audio restoration algorithms.
De-noise algorithms
There several techniques implemented in the library that are being used in the denoisers, such as masking thresholds estimation, onset detectors, etc. All these are being used in conjunction to improve the very basic spectral substraction algorithm. Most of the papers used are listed in the wiki of the project. Also a block diagram is provided to explain the reduction architecture.
Build
If you wish to compile yourself and install the library you will need the a C compiling toolchain, Meson build system, ninja compiler, git and fftw3 library.
Installation:
git clone https://github.com/lucianodato/noise-repellent.git
cd noise-repellent
meson build --buildtype=release --prefix=/usr --libdir=lib (your-os-appropriate-location-fullpath)
meson compile -C build -v
sudo meson install -C build
Example
Simple console apps examples are provided to demonstrate how to use the library. It needs libsndfile to compile successfully. You can use them as follows:
Adaptive noise learn
adenoise_demo <input file name> <output file name>
Manual noise learn
denoise_demo <input file name> <output file name>
It will recognize any libsndfile supported format.