Gsoc2019Ideas

Student Project Ideas for Google Summer of Code 2019

This page lists the suggested projects for students working on Mixxx as part of Google Summer of Code 2019. Each of these projects represents something that we think would make a really big difference to our users and that we as a development team are really excited about. If you are interested in applying to GSoC, read GSoC Advice before applying or getting involved.

A GSoC application that simply repeats the project description will NOT be accepted. We expect you to think about the feature and how it aligns with Mixxx's goals, describe potential use cases and propose a plan for implementing a solution. Only students that are active members of the Mixxx community are accepted. If this is not the case yet, just say hello at https://mixxx.zulipchat.com and discuss your Ideas and use cases with us.

Measures, Downbeats, Bars and Phrases

Mixxx uses information about the tempo and location of beats for many features including sync, looping, and quantize cue points.

For a smooth transition between tracks it is also required to sync the bars, the first beat in a measure. Currently the DJ counts the beats 1 2 3 4 and places the CUE at such a beat 1 (downbeat) of the incoming track by listening to the track in headphones. Now he can count the playing track and hit play at beat 1. Mixxx can help and adjust this exactly to the desired beat, but unfortunately not more. See: video tutorial

Most tracks have a 4/4 measure but Mixxx should also allow less common measures like 3/4 or 7/8. This would be major benefit compared to other DJ software that assumes that all music has a 4/4 measure, which is incorrect for lots of music. Currently Mixxx is not aware of bars and measures. It is a part of the project to place bars on the auto detected beat grids by a new editor and visualize them on the waveform.

The project might be extended towards a sync feature using this new info or into a feature that auto detect bars and phases.

Changing Tempo Tracks

Currently, Mixxx assumes either that tracks have a constant tempo for their entire duration or always changing tempo. The first option works nice for most electronic tracks, because it creates a reliable beat grid, even if some beats are not detected. It fails for hand made track where a drummer has no crystal clock in his head. In this case the second approach works better. But if you try to sync an other track to the hand made track it is yowling because it tries to exactly follow the drummer.

In this project you should find an approach that is able to iron out a small beat jitter of hand made tracks, but follow major tempo changes. It should be also be aware of breaks and britches and other difficult to detect elements.

One way to approach this would be to mark sections with changing tempos by special markers. For example, this video tutorial demonstrates how Serato DJ handles this.

A proposal for this project should allow for handling tracks that change time signatures.

The analyzer that Mixxx uses provides the exact locations of each beat. This might be used to automatically guess whether to treat a part of a track as a constant tempo or changing tempo.

A strong application will list some specific tracks with changing tempos that will be used for testing the new features. These should include both tracks played by live musicians and tracks produced on a grid in a computer. Also, the application should propose how the new information available in the beat grid could be edited by users in a fast, intuitive way. Students with backgrounds in music theory and/or playing percussion instruments are encouraged to apply for this project, but these are not requirements and we welcome your application if you do not have that experience.