Play-along click beat on recordings

[alastair]

If we want to have a click track on recordings we need to decide how to do this. Because of browser limitations around audio latency, it might be better to render audio tracks offline and stream the click or clickless version depending on what people want. This requires being able to play a new track from partway through, and stopping downloading the other track.

First version of this will use clicks from @ajaysmurthy's manual annotations of http://compmusic.upf.edu/carnatic-rhythm-dataset

[ajaysmurthy]

There can be different types of clicks (depending on the rhythmic event) So it is definitely better to render offline and stream the click or clickless version as required.

[alastair]

An idea, I wonder if we can use ogg/vorbis and have multiple streams inside the container. This means we'd only need to download one file. I'm not sure about the support for this in file creation or reading. We'll need to look into it.

[alastair]

Browsers don't support multiple streams (yet - it's being discussed in firefox). An option be to use the web audio api (in firefox and chrome) to get access to the audio stream and overlay the clicks on top of this. Internet Explorer won't get the audio api until IE11, released later this year. So we'd either still need to render tracks offline, or ask people to upgrade.