AudioVisualizersData

Table of contents

1. Description
   1. Accessing the content of a dropped audio file
   2. Updating the content of a visualizer
      1. Quick Guide on juce::AudioBuffer<float>

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Description

The content of AudioVisualizersData placed in the tabs will be modifiable/accessible in the deploy() method using the audioVisualizersData instance.

You can update the content whenever the audio content changes. Moreover, when the user drops an audio file into the widget, the content of the audio visualizers will be provided to you in the deploy() method.

Accessing the content of a dropped audio file

The content of the dropped midi file, will be provided to you as a pair of juce::AudioBuffer and a double where the first corresponds to the audio data and the second to the sample rate.

As soon as an audio file is dropped on ANY of the visualizers, the deploy() method will be called with the new_audio_file_dropped_on_visualizers flag set to true. As such, check for this flag to be true, and then access the content of the dropped audio file:

    if (new_audio_file_dropped_on_visualizers) {
        auto ids = audioVisualizersData->get_visualizer_ids_with_user_dropped_new_audio();
        for (const auto& id : ids) {
            auto new_audios = audioVisualizersData->get_visualizer_data(id);
            if (new_audios != std::nullopt) {
                auto [audio, fs] = *new_audios;
                cout << "Audio File Dropped on Visualizer: " << id << endl;
                cout << "Audio File Length In Samples: " << audio.getNumSamples() << endl;
            }
        }
    }

Updating the content of a visualizer

You can update the content of a visualizer using the unique id of the visualizer specified in the settings.json file.

Make sure the audio data displayed is placed in a juce::AudioBuffer<float> instance.

    audioVisualizersData->clear_visualizer_data("AudioDisplay 1");
    float fs = 44100;
    audioVisualizersData->display_audio("AudioDisplay 1", audioBuffer, 44100.0f);

Quick Guide on juce::AudioBuffer<float>

In the following example, we will create a sine wave of 10 seconds duration

    # specify the sample rate
    float fs = 44100;
    
    # specify the duration of the audio in samples
    int duration_samples = int(fs * 10.0f);
    
    # create an empty audio buffer of 1 channel, 441000 samples (10 seconds) duration
    juce::AudioBuffer<float> audioBuffer(1, duration_samples);  
    
    // populate audioBuffer with 10 cycles of a sine wave
    for (int i = 0; i < duration_samples; i++) {
        audioBuffer.setSample(0, i, std::sin(i * 2 * M_PI / fs));
    }