Sonogram

Create a sonogram* from an wave form, or importing a .wav file.

The spectrogram can be saved as a .png file, a .csv file, or stored in memory. An example command line application is included that converts .wav files to .png spectrograms.

Example output .png:

*Note: sonogram, spectrograph, spectrogram, or power spectral density plots are common names of similar things.

Build and run the command line appplication

cargo build --release --bin sonogram --features=build-binary

./target/release/sonogram --wav samples/trumpet.wav --png output.png

Saving to a .png file

let waveform: Vec<i16> = vec![/* ... some data ... */];

// Build the model
let spectrograph = SpecOptionsBuilder::new(2048)
  .load_data_from_memory(waveform)
  .build().unwrap();

// Compute the spectrogram giving the number of bins and the window overlap.
spectrograph.compute();

// Specify a colour gradient to use (note you can create custom ones)
let mut gradient = ColourGradient::create(ColourTheme::from(args.gradient));

// Save the spectrogram to PNG.
let png_file = std::path::Path::new("path/to/file.png");
spectrograph.to_png(&png_file, 
            FrequencyScale::Linear,
            &mut gradient,
            512,    // Width
            512,    // Height
        ).unwrap();

Customise the colour gradient

For .png images you can customise the colour gradient:

let mut gradient = ColourGradient::new();
gradient.add_colour(RGBAColour::new(0, 0, 0, 255));     // Black
gradient.add_colour(RGBAColour::new(55, 0, 110, 255));  // Purple
gradient.add_colour(RGBAColour::new(0, 0, 180, 255));   // Blue
gradient.add_colour(RGBAColour::new(0, 255, 255, 255)); // Cyan
gradient.add_colour(RGBAColour::new(0, 255, 0, 255));   // Green
spec_builder.set_gradient(gradient);

Or use a built-in colour gradient theme:

let mut gradient = ColourGradient::rainbow_theme();
spec_builder.set_gradient(gradient);

License

This source is released under the GPLv3 license. Read the LICENSE file for legal information.