Esempio n. 1
0
/* extract log scaled, mel-shaped, frequency bins */
float *
recur_extract_log_freq_bins(RecurAudioBinner *ab, float *data){
  /* XXX assumes ab->value_size is 2 */
  const float *windowed_data = recur_apply_window(ab, data, data);
  gst_fft_f32_fft(ab->fft,
      windowed_data,
      ab->freq_data
  );
  return recur_bin_complex(ab, ab->freq_data);
}
void FFTFrame::doFFT(const float* data)
{
    gst_fft_f32_fft(m_fft, data, m_complexData);

    // Scale the frequency domain data to match vecLib's scale factor
    // on the Mac. FIXME: if we change the definition of FFTFrame to
    // eliminate this scale factor then this code will need to change.
    // Also, if this loop turns out to be hot then we should use SSE
    // or other intrinsics to accelerate it.
    float scaleFactor = 2;

    float* imagData = m_imagData.data();
    float* realData = m_realData.data();
    for (unsigned i = 0; i < unpackedFFTDataSize(m_FFTSize); ++i) {
        imagData[i] = m_complexData[i].i * scaleFactor;
        realData[i] = m_complexData[i].r * scaleFactor;
    }
}
static void
gst_spectrum_run_fft (GstSpectrum * spectrum, GstSpectrumChannel * cd,
    guint input_pos)
{
  guint i;
  guint bands = spectrum->bands;
  guint nfft = 2 * bands - 2;
  gint threshold = spectrum->threshold;
  gfloat *input = cd->input;
  gfloat *input_tmp = cd->input_tmp;
  gfloat *spect_magnitude = cd->spect_magnitude;
  gfloat *spect_phase = cd->spect_phase;
  GstFFTF32Complex *freqdata = cd->freqdata;
  GstFFTF32 *fft_ctx = cd->fft_ctx;

  for (i = 0; i < nfft; i++)
    input_tmp[i] = input[(input_pos + i) % nfft];

  gst_fft_f32_window (fft_ctx, input_tmp, GST_FFT_WINDOW_HAMMING);

  gst_fft_f32_fft (fft_ctx, input_tmp, freqdata);

  if (spectrum->message_magnitude) {
    gdouble val;
    /* Calculate magnitude in db */
    for (i = 0; i < bands; i++) {
      val = freqdata[i].r * freqdata[i].r;
      val += freqdata[i].i * freqdata[i].i;
      val /= nfft * nfft;
      val = 10.0 * log10 (val);
      if (val < threshold)
        val = threshold;
      spect_magnitude[i] += val;
    }
  }

  if (spectrum->message_phase) {
    /* Calculate phase */
    for (i = 0; i < bands; i++)
      spect_phase[i] += atan2 (freqdata[i].i, freqdata[i].r);
  }
}
static void
bp_vis_pcm_handoff (GstElement *sink, GstBuffer *buffer, GstPad *pad, gpointer userdata)
{
    BansheePlayer *player = (BansheePlayer*)userdata;
    GstStructure *structure;
    gint channels, wanted_size;
    gfloat *data;
    BansheePlayerVisDataCallback vis_data_cb;
    
    g_return_if_fail (IS_BANSHEE_PLAYER (player));
    
    vis_data_cb = player->vis_data_cb;

    if (vis_data_cb == NULL) {
        return;
    }

    if (player->vis_thawing) {
        // Flush our buffers out.
        gst_adapter_clear (player->vis_buffer);
        memset (player->vis_fft_sample_buffer, 0, sizeof(gfloat) * SLICE_SIZE);

        player->vis_thawing = FALSE;
    }
    
    structure = gst_caps_get_structure (gst_buffer_get_caps (buffer), 0);
    gst_structure_get_int (structure, "channels", &channels);
    
    wanted_size = channels * SLICE_SIZE * sizeof (gfloat);

    gst_adapter_push (player->vis_buffer, gst_buffer_copy (buffer));
    
    while ((data = (gfloat *)gst_adapter_peek (player->vis_buffer, wanted_size)) != NULL) {
        gfloat *deinterlaced = g_malloc (wanted_size);
        gfloat *specbuf = g_new (gfloat, SLICE_SIZE * 2);

        gint i, j;

        memcpy (specbuf, player->vis_fft_sample_buffer, SLICE_SIZE * sizeof(gfloat));
        
        for (i = 0; i < SLICE_SIZE; i++) {
            gfloat avg = 0.0f;

            for (j = 0; j < channels; j++) {
                gfloat sample = data[i * channels + j];

                deinterlaced[j * SLICE_SIZE + i] = sample;
                avg += sample;
            }

            avg /= channels;
            specbuf[i + SLICE_SIZE] = avg;
        }

        memcpy (player->vis_fft_sample_buffer, &specbuf[SLICE_SIZE], SLICE_SIZE * sizeof(gfloat));

        gst_fft_f32_window (player->vis_fft, specbuf, GST_FFT_WINDOW_HAMMING);
        gst_fft_f32_fft (player->vis_fft, specbuf, player->vis_fft_buffer);

        for (i = 0; i < SLICE_SIZE; i++) {
            gfloat val;

            GstFFTF32Complex cplx = player->vis_fft_buffer[i];

            val = cplx.r * cplx.r + cplx.i * cplx.i;
            val /= SLICE_SIZE * SLICE_SIZE;
            val = 10.0f * log10f(val);

            val = (val + 60.0f) / 60.0f;
            if (val < 0.0f)
                val = 0.0f;

            specbuf[i] = val;
        }

        vis_data_cb (player, channels, SLICE_SIZE, deinterlaced, SLICE_SIZE, specbuf);
        
        g_free (deinterlaced);
        g_free (specbuf);

        gst_adapter_flush (player->vis_buffer, wanted_size);
    }
}