audio_waveform-ruby
The audio_waveform-ruby gem provides a Ruby API for access to audio waveform data files generated by the audiowaveform program.
Refer to the audiowaveform documentation for more information and this page for file format details.
Installation
To install:
$ gem install audio_waveform-ruby
or, if using bundler, add this line to your application's Gemfile:
gem 'audio_waveform-ruby', :require => 'audio_waveform'
or, to use the latest code from the GitHub repository:
gem 'audio_waveform-ruby', :require => 'audio_waveform',
:git => 'https://github.com/bbc/audio_waveform-ruby.git'
and run
$ bundle install
Usage
To use this Gem in your program, add:
require 'audio_waveform'
Then, to load and use data from an existing waveform data file:
waveform = AudioWaveform::WaveformDataFile.new(filename: "test.dat")
puts waveform.sample_rate # Returns audio sample rate, in Hz
puts waveform.bits # Returns resolution of waveform data points
puts waveform.samples_per_pixel # Returns waveform zoom level, in samples per pixel
puts waveform.size # Returns number of waveform data points
(0...waveform.size).each do |i|
puts waveform.min_sample(i) # Returns waveform minimum at index i
puts waveform.max_sample(i) # Returns waveform maximum at index i
end
To generate a binary representation of a waveform data file:
waveform = AudioWaveform::WaveformDataFile.new(filename: "test.dat")
data = waveform.to_binary
To save waveform data as a file in binary format:
waveform = AudioWaveform::WaveformDataFile.new(filename: "test.dat")
waveform.save_as_binary("output.dat")
To generate a JSON representation of a waveform data file:
waveform = AudioWaveform::WaveformDataFile.new(filename: "test.dat")
waveform.to_json
To save waveform data as a file in JSON format:
waveform = AudioWaveform::WaveformDataFile.new(filename: "test.dat")
waveform.save_as_json("output.json")
To create a new waveform data file:
waveform = AudioWaveform::WaveformDataFile.new(
sample_rate: 44100,
samples_per_pixel: 512,
bits: 8
)
waveform.append(-10, 10)
.append(-11, 11)
.append(-3, 3)
# etc
License
See COPYING for details.
Contributing
If you have a feature request or want to report a bug, we'd be happy to hear from you. Please either raise an issue, or fork the project and send us a pull request.
Authors
This software was written by Chris Needham, chris.needham at bbc.co.uk.
Copyright
Copyright 2020 British Broadcasting Corporation