# Library for Acoustic Signal Processing

Welcome to LASP: Library for Acoustic Signal Processing. LASP is a C++ library
with a Python interface which is supposed to acquire and process (multi) sensor data in real time on a PC and output results.

Current features that are implemented:
- Compile-time determination of the floating-point accuracy (32/64 bit)
- Fast convolution FIR filter implementation
- Sample rate decimation by an integer factor of 4.
- Octave filterbank FIR filters designed to comply with IEC 61260
  (1995).
- Averaged power spectra and power spectral density determination
  using Welch' method. Taper functions of Hann, Hamming, Bartlett and
  Blackman are provided.
- A thread-safe job queue including routines to create worker threads.
- Several linear algebra routines (wrappers around BLAS and LAPACK).
- A nice debug tracer implementation
- Third octave filter bank FIR filters designed to comply with IEC 61260
  (1995).
- Slow and fast time updates of (A/C/Z) weighted sound pressure levels

Future features (wish-list)
- Conventional and delay-and-sum beam-forming algorithms

For now, the source code is well-documented but it requires some
additional documentation (the math behind it). This will be published
in a sister repository (https://code.ascee.nl/ascee/lasp-doc).

If you have any question(s), please feel free to contact us: info@ascee.nl.

# Installation

## Dependencies

- `$ sudo apt install libopenblas-dev python3-pip python3-scipy libusb-dev libpulse-dev cmake-curses-gui python3-h5py`
- `$ pip3 install --user -r requirements.txt`


If building RtAudio with the ALSA backend, you will also require the following packages:

- libclalsadrv-dev

If building RtAudio with the Jack Audio Connection Kit (JACK) backend, you will also require the following packages:

- libjack-jackd2-dev

## Download & build

- `$ git clone --recursive https://code.ascee.nl/ASCEE/lasp.git`
- `$ cd lasp`

For a release build:

- `$ cmake .`

or optionally for a custom build:

- `$ ccmake .`

Configure and run:

- `$ make -j`

### Build documentation

`$ sudo apt install doxygen`

While still in lasp dir:

`$ doxygen`

This will build the documentation. It can be read by:

`$ <YOUR-BROWSER> doc/html/index.html`

## Install

For an editable install (while developing):

- `$ pip3 install --prefix=$HOME/.local -e .`

To install locally, for a fixed version:

- `$ pip3 install --prefix=$HOME/.local`

## Usage

- See examples directories for IPython notebooks.
- Please refer to the [documentation](https://lasp.ascee.nl/) for features.