Struct Spectrogram

pub struct Spectrogram { /* private fields */ }

Implementations

impl Spectrogram

pub fn from_raw<T: NumCast + Copy>( buf: &[T], width: usize, height: usize, ) -> Result<Spectrogram, SonogramError>

Create a new Spectrogram from a raw buffer. It must of the correct size (width * height). But can be of any numeric type that can be converted to f32.

Arguments

• buf - The raw buffer of data to create the spectrogram from, real numbers only.
• width - The width of the spectrogram.
• height - The height of the spectrogram.

pub fn to_png( &mut self, fname: &Path, freq_scale: FrequencyScale, gradient: &mut ColourGradient, w_img: usize, h_img: usize, ) -> Result<(), Error>

Save the calculated spectrogram as a PNG image.

Arguments

• fname - The path to the PNG to save to the filesystem.
• freq_scale - The type of frequency scale to use for the spectrogram.
• gradient - The colour gradient to use for the spectrogram.
• w_img - The output image width.
• h_img - The output image height.

pub fn to_png_in_memory( &mut self, freq_scale: FrequencyScale, gradient: &mut ColourGradient, w_img: usize, h_img: usize, ) -> Result<Vec<u8>, Error>

Create the spectrogram in memory as a PNG.

Arguments

• freq_scale - The type of frequency scale to use for the spectrogram.
• gradient - The colour gradient to use for the spectrogram.
• w_img - The output image width.
• h_img - The output image height.

pub fn to_rgba_in_memory( &mut self, freq_scale: FrequencyScale, gradient: &mut ColourGradient, w_img: usize, h_img: usize, ) -> Vec<u8>

Create the spectrogram in memory as raw RGBA format.

Arguments

• freq_scale - The type of frequency scale to use for the spectrogram.
• gradient - The colour gradient to use for the spectrogram.
• w_img - The output image width.
• h_img - The output image height.

pub fn to_csv( &mut self, fname: &Path, freq_scale: FrequencyScale, cols: usize, rows: usize, ) -> Result<(), Error>

Save the calculated spectrogram as a CSV file.

Arguments

• fname - The path to the CSV to save to the filesystem.
• freq_scale - The type of frequency scale to use for the spectrogram.
• cols - The number of columns.
• rows - The number of rows.

pub fn to_buffer( &self, freq_scale: FrequencyScale, img_width: usize, img_height: usize, ) -> Vec<f32>

Map the spectrogram to the output buffer. Essentially scales the frequency to map to the vertical axis (y-axis) of the output and scale the x-axis to match the output. It will also convert the spectrogram to dB.

Arguments

• freq_scale - The type of frequency scale to use for the spectrogram.
• img_width - The output image width.
• img_height - The output image height.

pub fn get_min_max(&self) -> (f32, f32)

Get the minimum and maximum values from the current spectrogram.

pub fn shape(&self) -> (usize, usize)

Get the width and height of the spectrogram.

pub fn row_iter<'a>( &'a self, row_idx: usize, ) -> impl Iterator<Item = &'a f32> + 'a

Get an iterator over the spectrogram data by row index.