panwave

A zero-dependency library for computing, decomposing, and reconstructing signals via wavelet packet trees.

Why panwave

Panwave is adapted from the wavelet packet tree component of a hobby project named PAN built way back in 2008. For the tenth anniversary of the project, panwave was split out into its own library and re-implemented in c++17. Panwave is the PAN wavelet (PanWave) component.

Using panwave

Panwave offers a simple interface for performing wavelet packet tree operations.

std::vector<double> signal = {0,1,2,3,4,5,6,7,8,9,10,11,12};
std::vector<double> reconstructed_signal;
reconstructed_signal.resize(signal.size());

// Load well-known wavelet coefficients.
Wavelet wavelet;
Wavelet::GetWaveletCoefficients(&wavelet, Wavelet::WaveletType::Daubechies, 4);

// Construct wavelet packet tree of height = 3.
// This tree has 4 wavelet levels, and 4 leaves.
WaveletPacketTree tree(3, &wavelet);
tree.SetRootSignal(signal);
tree.Decompose();

// Reconstruct signal one wavelet level at a time.
for (size_t i = 0; i < tree.GetWaveletLevelCount(); i++) {
    tree.Reconstruct(i);
    auto& root_signal = tree.GetRootSignal();
    
    // Add the coefficients of wavelet level i to the reconstructed signal.
    std::transform(reconstructed_signal.cbegin(), reconstructed_signal.cend(), root_signal.cbegin(), reconstructed_signal.begin(), std::plus<>());
}

// signal == reconstructed_signal

Building panwave

You can build panwave on any platform with a compiler which supports c++17 language standards mode. The library is designed to be portable and easy to add to your project. We do not release binaries here, but panwave compiles into a static library which can be added as a dependency. Add the panwave cmake file to your build system and you should be ready to use panwave.

Tested build configurations

Windows 10

• CMake 3.17.0
• Visual Studio 2019 16.11.23

Ubuntu 20.04

• CMake 3.16.3
• Clang 10.0.0

Testing panwave

The library ships with a simple test program in the panwave/test folder.

> git clone https://github.com/boingoing/panwave/panwave.git
> mkdir panwave/build
> cd panwave/build
> cmake ..
> make
> ./panwave_test

Documentation

https://boingoing.github.io/panwave/html/annotated.html