Class AudioBus

include/LabSound/core/AudioBus.h:22–148

An AudioBus represents a collection of one or more AudioChannels. The data layout is "planar" as opposed to "interleaved". An AudioBus with one channel is mono, an AudioBus with two channels is stereo, etc.

// The data layout is "planar" as opposed to "interleaved".
// An AudioBus with one channel is mono, an AudioBus with two channels is stereo, etc.
class AudioBus
{
    AudioBus(const AudioBus &);  // noncopyable

public:
    // Can define non-standard layouts here:
    enum
    {
        LayoutCanonical = 0
    };

    // allocate indicates whether or not to initially have the AudioChannels created with managed storage.
    // Normal usage is to pass true here, in which case the AudioChannels will memory-manage their own storage.
    // If allocate is false then setChannelMemory() has to be called later on for each channel before the AudioBus is useable...
    AudioBus(int numberOfChannels, int length, bool allocate = true);

    // Tells the given channel to use an externally allocated buffer.
    void setChannelMemory(int channelIndex, float * storage, int length);

    // Channels
    int numberOfChannels() const { return static_cast<int>(m_channels.size()); }

    // Use this when looping over channels
    AudioChannel * channel(int channel) { return m_channels[channel].get(); }

    const AudioChannel * channel(int channel) const
    {
        return const_cast<AudioBus *>(this)->m_channels[channel].get();
    }

    // use this when accessing channels semantically
    AudioChannel * channelByType(Channel type);
    const AudioChannel * channelByType(Channel type) const;

    // Number of sample-frames
    int length() const { return m_length; }

    // resizeSmaller() can only be called with a new length <= the current length.
    // The data stored in the bus will remain undisturbed.
    void resizeSmaller(int newLength);

    // Sample-rate : 0.0 if unknown or "don't care"
    float sampleRate() const { return m_sampleRate; }
    void setSampleRate(float sampleRate) { m_sampleRate = sampleRate; }

    // Zeroes all channels.
    void zero();

    // Clears the silent flag on all channels.
    void clearSilentFlag();

    // Returns true if the silent bit is set on all channels.
    bool isSilent() const;
    
    // Returns true if all channels hold zeros.
    // meant for debugging as it scans the data.
    bool isZero() const;