Features and Design Goals
Sonic Visualiser contains features for the following:
- Load audio files in WAV, Ogg and MP3 formats, and view
their waveforms.
- Look at audio visualisations such as spectrogram views, with
interactive adjustment of display parameters.
- Annotate audio data by adding labelled time points and defining
segments, point values and curves.
- Overlay annotations on top of one another with aligned
scales, and overlay annotations on top of waveform or
spectrogram views.
- View the same data at multiple time resolutions
simultaneously (for close-up and overview).
- Run feature-extraction plugins to calculate annotations
automatically, using algorithms such as beat trackers, pitch
detectors and so on.
- Import annotation layers from various text file formats.
- Import note data from MIDI files, view it alongside other
frequency scales, and play it with the original audio.
- Play back the audio plus synthesised annotations, taking
care to synchronise playback with display.
- Select areas of interest, optionally snapping to nearby
feature locations, and audition individual and comparative
selections in seamless loops.
- Time-stretch playback, slowing right down or speeding up
to a tiny fraction or huge multiple of the original speed
while retaining a synchronised display.
- Export audio regions and annotation layers to external files.
The design goals for Sonic Visualiser are:
- To provide the best available core
waveform and spectrogram audio visualisations for use with
substantial files of music audio data.
- To facilitate ready comparisons between different kinds of
data, for example by making it easy to overlay one set of data
on another, or display the same data in more than one way at the
same time.
- To be straightforward. The user interface should be simpler
to learn and to explain than the internal data structures. In
this respect, Sonic Visualiser aims to resemble a consumer
audio application.
- To be responsive, slick, and enjoyable. Even if you have to
wait for your results to be calculated, you should be able to do
something else with the audio data while you wait. Sonic
Visualiser is pervasively multithreaded, loves multiprocessor
and multicore systems, and can make good use of fast processors
with plenty of memory.
- To handle large data sets. The work Sonic Visualiser does
is intrinsically processor-hungry and (often) memory-hungry, but
the aim is to allow you to work with long audio files on
machines with modest CPU and memory where reasonable. (Disk
space is another matter. Sonic Visualiser eats that.)