public void InverseFft(Gst.FFT.FFTF32Complex freqdata, float timedata)
{
IntPtr native_freqdata = GLib.Marshaller.StructureToPtrAlloc(freqdata);
gst_fft_f32_inverse_fft(Handle, native_freqdata, timedata);
Marshal.FreeHGlobal(native_freqdata);
}
private void PCMHandoff(object o, GLib.SignalArgs args)
{
byte[] data;
uint wanted_size;
if (OnDataAvailable == null)
{
return;
}
if (vis_thawing)
{
// Flush our buffers out.
vis_buffer.Clear();
System.Array.Clear(vis_fft_sample_buffer, 0, vis_fft_sample_buffer.Length);
vis_thawing = false;
}
Caps caps = ((Gst.Pad)args.Args [1]).CurrentCaps;
Structure structure = caps [0];
int channels = (int)structure.GetValue("channels").Val;
wanted_size = (uint)(channels * SLICE_SIZE * sizeof(float));
//TODO see if buffer need a copy or not
//but copy is no available in gst# ;(
vis_buffer.Push((Gst.Buffer)args.Args[0]);
int i, j;
while ((data = vis_buffer.Map()) != null)
{
float[] buff = new float[data.Length];
float[] deinterlaced = new float [channels * SLICE_SIZE];
float[] specbuf = new float [SLICE_SIZE * 2];
System.Array.Copy(specbuf, vis_fft_sample_buffer, SLICE_SIZE);
for (i = 0; i < SLICE_SIZE; i++)
{
float avg = 0.0f;
for (j = 0; j < channels; j++)
{
float sample = buff[i * channels + j];
deinterlaced[j * SLICE_SIZE + i] = sample;
avg += sample;
}
avg /= channels;
specbuf[i + SLICE_SIZE] = avg;
}
System.Array.Copy(vis_fft_sample_buffer, 0, specbuf, SLICE_SIZE, SLICE_SIZE);
vis_fft.Window(specbuf, Gst.FFT.FFTWindow.Hamming);
vis_fft.Fft(specbuf, vis_fft_buffer);
for (i = 0; i < SLICE_SIZE; i++)
{
float val;
Gst.FFT.FFTF32Complex cplx = vis_fft_buffer[i];
val = cplx.R * cplx.R + cplx.I * cplx.I;
val /= SLICE_SIZE * SLICE_SIZE;
val = (float)(10.0f * System.Math.Log10((double)val));
val = (val + 60.0f) / 60.0f;
if (val < 0.0f)
{
val = 0.0f;
}
specbuf[i] = val;
}
float [] flat = new float[channels * SLICE_SIZE];
System.Array.Copy(deinterlaced, flat, flat.Length);
float [][] cbd = new float[channels][];
for (int k = 0; k < channels; k++)
{
float [] channel = new float[SLICE_SIZE];
System.Array.Copy(flat, k * SLICE_SIZE, channel, 0, SLICE_SIZE);
cbd [k] = channel;
}
float [] spec = new float [SLICE_SIZE];
System.Array.Copy(specbuf, spec, SLICE_SIZE);
try {
OnDataAvailable(cbd, new float[][] { spec });
} catch (System.Exception e) {
Log.Error("Uncaught exception during visualization data post.", e);
}
vis_buffer.Flush((uint)wanted_size);
}
}
