Multi Channel File Mixing

Multiple-channel file mixing

OGG and FLAC files support up to eight channels. It would be interesting to extend Mixxx to allow DJs to work with these channels individually within a virtual deck so as to be able to create live remixes from stems. Doing this from a single multi-channel file greatly simplifies the workflow and eliminates synchronization problems.

Things that need to change for this to be implemented:

• FLAC and OGG SoundSources need to find out how many channels the loaded file offers, get meta-data for each (whether any are stereo pairs/other groups,) and report this information to their parent Deck.
• Decks need to:
• Ask for this information
• Manage the supplied number of channels
• Offer additional controls for each mono channel or channel group: Mute, Solo, Volume, and Pan controls
• CachingReader needs to be extended to support up to eight channels
• The GUI needs to:
• Include additional parallel summary waveforms for each mono channel or stereo pair
• Display Mute, Solo, Volume, and Pan controls as the Deck reports
• Overlap all (active) channels' waveforms in the detailed waveform display

SoundSource API changes

    int getNumberOfChannels(); // Number of mono channels in the loaded file
    QString[] getChannelNames(); // Name for each channel - from FLAC/OGG tags
    QList(int[]) getLinkedChannels(); // List of channel groups to treat as one unit (Stereo pairs, surround channels)