Add documentation on how to fill a buffer with samples

[ScienceMarc]

// 1. Create an AudioBuffer
// (BTW, AudioBuffer is just a vector of vectors)

AudioFile::AudioBuffer buffer;

// 2. Set to (e.g.) two channels
buffer.resize (2);

// 3. Set number of samples per channel
buffer[0].resize (100000);
buffer[1].resize (100000);

// 4. do something here to fill the buffer with samples

// 5. Put into the AudioFile object
bool ok = audioFile.setAudioBuffer (buffer);

Step 4 is way too vague. How do I actually add samples?

[adamstark]

Hi Marc,

Thanks for getting in touch. I will perhaps update this for the next version, or maybe with some example code. But for now, here is what I would do at step 4 to fill a buffer with a sine wave... (i've added some extra variables for clarity):

int numChannels = 2;
int numSamplesPerChannel = 100000;
float sampleRate = 44100.f;
float frequency = 440;

for (int i = 0; i < numSamplesPerChannel; i++)
{
        float sample = sinf (2. * M_PI * ((float) i / sampleRate) * frequency) ;
        
        for (int channel = 0; channel < numChannels; channel++)
             buffer[channel][i] = sample * 0.5;
}

I haven't tested this - just wrote it here, but it should work. Hope this helps.

Adam

[ScienceMarc]

Thank you so much for your quick response. This worked.

[adamstark]

I've now added this to the main documentation in the new version