A few days ago a discussion in the Freak Show podcast pointed to an interesting BBC research project to render audio waveforms in the browser.
We now added a new output file format (Waveform Data File), which is generated by the open source tool audiowaveform and can be used to display interactive audio waveform data using the Peaks.js java script library. Here is an example screenshot:

(image from BBC R&D blog)

The tool includes features to zoom in waveforms, to mark segments in audio files (could be interesting for chapter marks) and can be easily integrated ...