Mp3 player & Oscilloscope ?!

General JUCE discussion
21

ok, thanks for the help.

22

Is the JUCE AudioVisualiser class what you're looking for?

http://www.juce.com/doc/classAudioVisualiserComponent

You can see it in action in the JUCE demo, I use it whenever I want to display an audio signal.

23

Yes, the AudioVisualiserComponent is a ready-to-use scrolling waveform display. This is something else than an oscilloscope. Sorry, there was apparently some confusion about the terminilogy here!

This is a scrolling waveform display:

This is an oscilloscope:

24

AudioVizualiser is used only for waveform audio and oscilloscope is something different.

Timur explained well the difference between them.

What I was looking for was an oscilloscope. 

Thanks. ;)

25

I also had trouble with audioDeviceIOCallback distorting the sound, but then I looked at AudioLiveScrollingDisplay.h in the Juce Demo and noticed that it is important to clear any unused channel data. So it works great now with this change:

      void audioDeviceIOCallback (const float** inputChannelData,
                                    int numInputChannels,
                                    float** outputChannelData,
                                    int numOutputChannels,
                                    int numSamples) override
{
    // show the waveform in the oscilloscpe
    audioOscilloscope.pushBuffer(*outputChannelData, numSamples);
    // We need to clear the output buffers before returning, in case they're full of junk..
    for (int j = 0; j < numOutputChannels; ++j)
    {
        if (float* outputChannel = outputChannelData[j])
        {
            zeromem (outputChannel, sizeof (float) * (size_t) numSamples);
        }
    }
}