Gsoc2008 Waveform Rewrite

Creating a new Waveform View handler for Mixxx (GSoC 2008 project)

• Student: Russell Ryan
• Mentor: Albert Santoni

Abstract

The current Mixxx waveform view is in need of a refresh. In its current state it is not flexible enough to support desirable new features, and it also causes performance issues that can cause skipping in the audio. Redesigning the waveform view will both provide Mixxx with a more feature-full waveform view and hopefully alleviate these performance issues.

The goal of the project is to rewrite the Mixxx waveform view. The new waveform view will support all the current features of the waveform view, and more. The new viewer will be designed to be flexible enough to support improvements and features that could come in the future.

Features of the waveform viewer include:

• A display of a waveform with time on the horizontal axis and amplitude on the vertical axis.
• A center 'mark' which indicates the current position of the player on the waveform.
• 'beat frames' which coordinate with Mixxx's beat detection algorithms to render markers on each detected beat in the waveform
• Coloring of the waveform based on the 'timbre' or sound feel of the waveform.
• Integration with the GUI (or vinyl control interfaces) to support dragging of the waveform back and forth
• Support for drag-and-dropping a song onto a 'virtual deck' to load the song into that deck
• Support for an arbitrary number of audio streams for which to display waveforms
• Support for markers or other meta-indicators to be set on the waveform to serve as visual feedback to the user. This will be useful for implementing features such as looping controls.

These features will be implemented over the course of the summer of 2008. Checkpoints and measurable progress indicators will be used to ensure development is on schedule.