gstreamer/gst/spectrum/gstspectrum.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 *               <2006> Stefan Kost <ensonic@users.sf.net>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */
/**
 * SECTION:element-spectrum
 *
 * <refsect2>
 * The Spectrum element analyzes the frequency spectrum of an audio signal.
 * If <link linkend="GstSpectrum--message">message property</link> is #TRUE it
 * sends analysis results as application message named
 * <classname>&quot;spectrum&quot;</classname> after each interval of time given
 * by the <link linkend="GstSpectrum--interval">interval property</link>.
 * The message's structure contains two fields:
 * <itemizedlist>
 * <listitem>
 *   <para>
 *   #GstClockTime
 *   <classname>&quot;endtime&quot;</classname>:
 *   the end time of the buffer that triggered the message
 *   </para>
 * </listitem>
 * <listitem>
 *   <para>
 *   #GstValueList of #guchar
 *   <classname>&quot;spectrum&quot;</classname>:
 *   the level for each frequency band. A value of 0 maps to the
 *   db value given by the
 *   <link linkend="GstSpectrum--threshold">threshold property.</link>.
 *   </para>
 * </listitem>
 *
 * This element cannot be used with the gst-launch command in a sensible way.
 * The included demo shows how to use it in an application.
 *
 * Last reviewed on 2006-05-21 (0.10.3)
 * </refsect2>
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <gst/audio/audio.h>
#include "gstspectrum.h"

GST_DEBUG_CATEGORY_STATIC (gst_spectrum_debug);
#define GST_CAT_DEFAULT gst_spectrum_debug

/* elementfactory information */
static const GstElementDetails gst_spectrum_details =
GST_ELEMENT_DETAILS ("Spectrum analyzer",
    "Filter/Analyzer/Audio",
    "Run an FFT on the audio signal, output spectrum data",
    "Erik Walthinsen <omega@cse.ogi.edu>, "
    "Stefan Kost <ensonic@users.sf.net>");

static GstStaticPadTemplate sink_template_factory =
GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("audio/x-raw-int, "
        "rate = (int) [ 1, MAX ], "
        "channels = (int) [1, MAX], "
        "endianness = (int) BYTE_ORDER, "
        "width = (int) 16, " "depth = (int) 16, " "signed = (boolean) true")
    );

static GstStaticPadTemplate src_template_factory =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("audio/x-raw-int, "
        "rate = (int) [ 1, MAX ], "
        "channels = (int) [1, MAX], "
        "endianness = (int) BYTE_ORDER, "
        "width = (int) 16, " "depth = (int) 16, " "signed = (boolean) true")
    );

/* Spectrum properties */
#define DEFAULT_SIGNAL_SPECTRUM		TRUE
#define DEFAULT_SIGNAL_INTERVAL		(GST_SECOND / 10)
#define DEFAULT_BANDS			128
#define DEFAULT_THRESHOLD		-60

#define SPECTRUM_WINDOW_BASE 9
#define SPECTRUM_WINDOW_LEN (1 << (SPECTRUM_WINDOW_BASE+1))

enum
{
  PROP_0,
  PROP_SIGNAL_SPECTRUM,
  PROP_SIGNAL_INTERVAL,
  PROP_BANDS,
  PROP_THRESHOLD
};

GST_BOILERPLATE (GstSpectrum, gst_spectrum, GstBaseTransform,
    GST_TYPE_BASE_TRANSFORM);

static void gst_spectrum_dispose (GObject * object);
static void gst_spectrum_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_spectrum_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);
static gboolean gst_spectrum_set_caps (GstBaseTransform * trans, GstCaps * in,
    GstCaps * out);
static gboolean gst_spectrum_start (GstBaseTransform * trans);
static gboolean gst_spectrum_stop (GstBaseTransform * trans);
static gboolean gst_spectrum_event (GstBaseTransform * trans, GstEvent * event);
static GstFlowReturn gst_spectrum_transform_ip (GstBaseTransform * trans,
    GstBuffer * in);


#define fixed short
extern int gst_spectrum_fix_fft (fixed fr[], fixed fi[], int m, int inverse);
extern void gst_spectrum_fix_loud (fixed loud[], fixed fr[], fixed fi[], int n,
    int scale_shift);
extern void gst_spectrum_window (fixed fr[], int n);

static void
gst_spectrum_base_init (gpointer g_class)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&sink_template_factory));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&src_template_factory));
  gst_element_class_set_details (element_class, &gst_spectrum_details);
}

static void
gst_spectrum_class_init (GstSpectrumClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstBaseTransformClass *trans_class = GST_BASE_TRANSFORM_CLASS (klass);

  gobject_class->set_property = gst_spectrum_set_property;
  gobject_class->get_property = gst_spectrum_get_property;
  gobject_class->dispose = gst_spectrum_dispose;

  trans_class->set_caps = GST_DEBUG_FUNCPTR (gst_spectrum_set_caps);
  trans_class->start = GST_DEBUG_FUNCPTR (gst_spectrum_start);
  trans_class->stop = GST_DEBUG_FUNCPTR (gst_spectrum_stop);
  trans_class->event = GST_DEBUG_FUNCPTR (gst_spectrum_event);
  trans_class->transform_ip = GST_DEBUG_FUNCPTR (gst_spectrum_transform_ip);
  trans_class->passthrough_on_same_caps = TRUE;

  g_object_class_install_property (gobject_class, PROP_SIGNAL_SPECTRUM,
      g_param_spec_boolean ("message", "Message",
          "Post a level message for each passed interval",
          DEFAULT_SIGNAL_SPECTRUM, G_PARAM_READWRITE));

  g_object_class_install_property (gobject_class, PROP_SIGNAL_INTERVAL,
      g_param_spec_uint64 ("interval", "Interval",
          "Interval of time between message posts (in nanoseconds)",
          1, G_MAXUINT64, DEFAULT_SIGNAL_INTERVAL, G_PARAM_READWRITE));

  g_object_class_install_property (gobject_class, PROP_BANDS,
      g_param_spec_uint ("bands", "Bands", "number of frequency bands",
          0, G_MAXUINT, DEFAULT_BANDS, G_PARAM_READWRITE));

  g_object_class_install_property (gobject_class, PROP_THRESHOLD,
      g_param_spec_int ("threshold", "Threshold",
          "db threshold for result, maps to 0", G_MININT, 0, DEFAULT_THRESHOLD,
          G_PARAM_READWRITE));

  GST_DEBUG_CATEGORY_INIT (gst_spectrum_debug, "spectrum", 0,
      "audio spectrum analyser element");
}

static void
gst_spectrum_init (GstSpectrum * spectrum, GstSpectrumClass * g_class)
{
  spectrum->adapter = gst_adapter_new ();

  spectrum->message = DEFAULT_SIGNAL_SPECTRUM;
  spectrum->interval = DEFAULT_SIGNAL_INTERVAL;
  spectrum->bands = DEFAULT_BANDS;
  spectrum->threshold = DEFAULT_THRESHOLD;

  spectrum->loud = g_malloc (SPECTRUM_WINDOW_LEN * sizeof (gint16));
  spectrum->im = g_malloc0 (SPECTRUM_WINDOW_LEN * sizeof (gint16));
  spectrum->re = g_malloc0 (SPECTRUM_WINDOW_LEN * sizeof (gint16));
  spectrum->spect = g_malloc (spectrum->bands * sizeof (guchar));
}

static void
gst_spectrum_dispose (GObject * object)
{
  GstSpectrum *spectrum = GST_SPECTRUM (object);

  if (spectrum->adapter) {
    g_object_unref (spectrum->adapter);
    spectrum->adapter = NULL;
  }

  g_free (spectrum->re);
  g_free (spectrum->im);
  g_free (spectrum->loud);
  g_free (spectrum->spect);

  spectrum->re = NULL;
  spectrum->im = NULL;
  spectrum->loud = NULL;
  spectrum->spect = NULL;

  G_OBJECT_CLASS (parent_class)->dispose (object);
}

static void
gst_spectrum_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstSpectrum *filter = GST_SPECTRUM (object);

  switch (prop_id) {
    case PROP_SIGNAL_SPECTRUM:
      filter->message = g_value_get_boolean (value);
      break;
    case PROP_SIGNAL_INTERVAL:
      filter->interval = g_value_get_uint64 (value);
      break;
    case PROP_BANDS:
      GST_BASE_TRANSFORM_LOCK (filter);
      filter->bands = g_value_get_uint (value);
      g_free (filter->spect);
      filter->spect = g_malloc (filter->bands * sizeof (guchar));
      GST_BASE_TRANSFORM_UNLOCK (filter);
      GST_DEBUG_OBJECT (filter, "reallocation, spect = %p, bands =%d ",
          filter->spect, filter->bands);
      break;
    case PROP_THRESHOLD:
      filter->threshold = g_value_get_int (value);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_spectrum_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  GstSpectrum *filter = GST_SPECTRUM (object);

  switch (prop_id) {
    case PROP_SIGNAL_SPECTRUM:
      g_value_set_boolean (value, filter->message);
      break;
    case PROP_SIGNAL_INTERVAL:
      g_value_set_uint64 (value, filter->interval);
      break;
    case PROP_BANDS:
      g_value_set_uint (value, filter->bands);
      break;
    case PROP_THRESHOLD:
      g_value_set_int (value, filter->threshold);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static gboolean
gst_spectrum_set_caps (GstBaseTransform * trans, GstCaps * in, GstCaps * out)
{
  GstSpectrum *filter = GST_SPECTRUM (trans);
  GstStructure *structure;

  structure = gst_caps_get_structure (in, 0);
  gst_structure_get_int (structure, "rate", &filter->rate);
  gst_structure_get_int (structure, "channels", &filter->channels);

  return TRUE;
}

static gboolean
gst_spectrum_start (GstBaseTransform * trans)
{
  GstSpectrum *filter = GST_SPECTRUM (trans);

  filter->num_frames = 0;
  gst_segment_init (&filter->segment, GST_FORMAT_UNDEFINED);

  return TRUE;
}

static gboolean
gst_spectrum_stop (GstBaseTransform * trans)
{
  GstSpectrum *filter = GST_SPECTRUM (trans);

  gst_adapter_clear (filter->adapter);

  return TRUE;
}

static gboolean
gst_spectrum_event (GstBaseTransform * trans, GstEvent * event)
{
  GstSpectrum *filter = GST_SPECTRUM (trans);

  switch (GST_EVENT_TYPE (event)) {
    case GST_EVENT_FLUSH_STOP:
    case GST_EVENT_EOS:
      gst_adapter_clear (filter->adapter);
      break;
    case GST_EVENT_NEWSEGMENT:{
      GstFormat format;
      gdouble rate, arate;
      gint64 start, stop, time;
      gboolean update;

      /* the newsegment values are used to clip the input samples
       * and to convert the incomming timestamps to running time */
      gst_event_parse_new_segment_full (event, &update, &rate, &arate, &format,
          &start, &stop, &time);

      /* now configure the values */
      gst_segment_set_newsegment_full (&filter->segment, update,
          rate, arate, format, start, stop, time);
      break;
    }
    default:
      break;
  }

  return TRUE;
}

static GstMessage *
gst_spectrum_message_new (GstSpectrum * spectrum, GstClockTime endtime)
{
  GstStructure *s;
  GValue v = { 0, };
  GValue *l;
  guint i;
  guchar *spect = spectrum->spect;

  GST_DEBUG_OBJECT (spectrum, "preparing message, spect = %p, bands =%d ",
      spect, spectrum->bands);

  s = gst_structure_new ("spectrum", "endtime", GST_TYPE_CLOCK_TIME,
      endtime, NULL);

  g_value_init (&v, GST_TYPE_LIST);
  /* will copy-by-value */
  gst_structure_set_value (s, "spectrum", &v);
  g_value_unset (&v);

  g_value_init (&v, G_TYPE_UCHAR);
  l = (GValue *) gst_structure_get_value (s, "spectrum");
  for (i = 0; i < spectrum->bands; i++) {
    g_value_set_uchar (&v, spect[i]);
    gst_value_list_append_value (l, &v);        /* copies by value */
  }
  g_value_unset (&v);

  return gst_message_new_element (GST_OBJECT (spectrum), s);
}

static GstFlowReturn
gst_spectrum_transform_ip (GstBaseTransform * trans, GstBuffer * in)
{
  GstSpectrum *spectrum = GST_SPECTRUM (trans);
  gint wanted;
  gint i, j, k;
  gint32 acc;
  gfloat pos, step;
  guchar *spect = spectrum->spect;

  GstClockTime endtime =
      gst_segment_to_running_time (&spectrum->segment, GST_FORMAT_TIME,
      GST_BUFFER_TIMESTAMP (in));
  GstClockTime blktime =
      GST_FRAMES_TO_CLOCK_TIME (SPECTRUM_WINDOW_LEN, spectrum->rate);

  GST_LOG_OBJECT (spectrum, "input size: %d bytes", GST_BUFFER_SIZE (in));

  gst_adapter_push (spectrum->adapter, gst_buffer_ref (in));
  /* required number of bytes */
  wanted = spectrum->channels * SPECTRUM_WINDOW_LEN * sizeof (gint16);
  /* FIXME: 4.0 was 2.0 before, but that include the mirrored spectrum */
  step = (gfloat) SPECTRUM_WINDOW_LEN / (spectrum->bands * 4.0);

  while (gst_adapter_available (spectrum->adapter) >= wanted) {
    const gint16 *samples;

    samples = (const gint16 *) gst_adapter_peek (spectrum->adapter, wanted);

    /* the current fft code is gint16 based, so supporting other formats would
     * not really benefit now */
    for (i = 0, j = 0; i < SPECTRUM_WINDOW_LEN; i++) {
      /* convert to mono */
      for (k = 0, acc = 0; k < spectrum->channels; k++)
        acc += samples[j++];
      spectrum->re[i] = (gint16) (acc / spectrum->channels);
    }

    gst_spectrum_window (spectrum->re, SPECTRUM_WINDOW_LEN);
    gst_spectrum_fix_fft (spectrum->re, spectrum->im, SPECTRUM_WINDOW_BASE,
        FALSE);
    gst_spectrum_fix_loud (spectrum->loud, spectrum->re, spectrum->im,
        SPECTRUM_WINDOW_LEN, 0);

    /* resample to requested number of bands */
    for (i = 0, pos = 0.0; i < spectrum->bands; i++, pos += step) {
      if (spectrum->loud[(gint) pos] > spectrum->threshold) {
        spect[i] = spectrum->loud[(gint) pos] - spectrum->threshold;
        /*
           if (spect[i] > 15);
           spect[i] = 15;
         */
      } else
        /* treat as silence */
        spect[i] = 0;
    }

    spectrum->num_frames += SPECTRUM_WINDOW_LEN;
    endtime += blktime;
    /* do we need to message ? */
    if (spectrum->num_frames >=
        GST_CLOCK_TIME_TO_FRAMES (spectrum->interval, spectrum->rate)) {
      if (spectrum->message) {
        GstMessage *m = gst_spectrum_message_new (spectrum, endtime);

        gst_element_post_message (GST_ELEMENT (spectrum), m);
      }
      spectrum->num_frames = 0;
    }

    gst_adapter_flush (spectrum->adapter, wanted);
  }

  return GST_FLOW_OK;
}

static gboolean
plugin_init (GstPlugin * plugin)
{
  return gst_element_register (plugin, "spectrum", GST_RANK_NONE,
      GST_TYPE_SPECTRUM);
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    "spectrum",
    "Run an FFT on the audio signal, output spectrum data",
    plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)