gstreamer/ext/mad/gstmad.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 *
 * 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.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>
#include "gstmad.h"

#define GST_TYPE_MAD \
  (gst_mad_get_type())
#define GST_MAD(obj) \
  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_MAD,GstMad))
#define GST_MAD_CLASS(klass) \
  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_MAD,GstMad))
#define GST_IS_MAD(obj) \
  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_MAD))
#define GST_IS_MAD_CLASS(obj) \
  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_MAD))


typedef struct _GstMad GstMad;
typedef struct _GstMadClass GstMadClass;

struct _GstMad
{
  GstElement element;

  /* pads */
  GstPad *sinkpad, *srcpad;

  /* state */
  struct mad_stream stream;
  struct mad_frame frame;
  struct mad_synth synth;
  guchar *tempbuffer;           /* temporary buffer to serve to mad */
  glong tempsize;               /* running count of temp buffer size */
  GstClockTime last_ts;
  guint64 base_byte_offset;
  guint64 bytes_consumed;       /* since the base_byte_offset */
  guint64 total_samples;        /* the number of samples since the sync point */

  gboolean in_error;            /* set when mad's in an error state */
  gboolean restart;
  guint64 segment_start;

  /* info */
  struct mad_header header;
  gboolean new_header;
  guint framecount;
  gint vbr_average;             /* average bitrate */
  guint64 vbr_rate;             /* average * framecount */

  gboolean half;
  gboolean ignore_crc;

  GstTagList *tags;

  /* negotiated format */
  gint rate;
  gint channels;

  gboolean caps_set;            /* used to keep track of whether to change/update caps */
  GstIndex *index;
  gint index_id;

  gboolean check_for_xing;
};

struct _GstMadClass
{
  GstElementClass parent_class;
};

/* elementfactory information */
static GstElementDetails gst_mad_details =
GST_ELEMENT_DETAILS ("mad mp3 decoder",
    "Codec/Decoder/Audio",
    "Uses mad code to decode mp3 streams",
    "Wim Taymans <wim.taymans@chello.be>");


/* Mad signals and args */
enum
{
  /* FILL ME */
  LAST_SIGNAL
};

enum
{
  ARG_0,
  ARG_HALF,
  ARG_IGNORE_CRC,
  ARG_METADATA,
  ARG_STREAMINFO
      /* FILL ME */
};

GST_DEBUG_CATEGORY_STATIC (mad_debug);
#define GST_CAT_DEFAULT mad_debug

static GstStaticPadTemplate mad_src_template_factory =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("audio/x-raw-int, "
        "endianness = (int) " G_STRINGIFY (G_BYTE_ORDER) ", "
        "signed = (boolean) true, "
        "width = (int) 16, "
        "depth = (int) 16, "
        "rate = (int) [ 11025, 48000 ], " "channels = (int) [ 1, 2 ]")
    );

static GstStaticPadTemplate mad_sink_template_factory =
GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("audio/mpeg, "
        "mpegversion = (int) 1, " "layer = (int) [ 1, 3 ]")
    );

static void gst_mad_base_init (gpointer g_class);
static void gst_mad_class_init (GstMadClass * klass);
static void gst_mad_init (GstMad * mad);
static void gst_mad_dispose (GObject * object);

static void gst_mad_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_mad_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);

static gboolean gst_mad_src_event (GstPad * pad, GstEvent * event);
static const GstFormat *gst_mad_get_formats (GstPad * pad);
static const GstEventMask *gst_mad_get_event_masks (GstPad * pad);
static const GstQueryType *gst_mad_get_query_types (GstPad * pad);

static gboolean gst_mad_src_query (GstPad * pad, GstQueryType type,
    GstFormat * format, gint64 * value);
static gboolean gst_mad_convert_sink (GstPad * pad, GstFormat src_format,
    gint64 src_value, GstFormat * dest_format, gint64 * dest_value);
static gboolean gst_mad_convert_src (GstPad * pad, GstFormat src_format,
    gint64 src_value, GstFormat * dest_format, gint64 * dest_value);

static void gst_mad_chain (GstPad * pad, GstData * _data);

static GstElementStateReturn gst_mad_change_state (GstElement * element);

static void gst_mad_set_index (GstElement * element, GstIndex * index);
static GstIndex *gst_mad_get_index (GstElement * element);


static GstElementClass *parent_class = NULL;

/* static guint gst_mad_signals[LAST_SIGNAL] = { 0 }; */

GType
gst_mad_get_type (void)
{
  static GType mad_type = 0;

  if (!mad_type) {
    static const GTypeInfo mad_info = {
      sizeof (GstMadClass),
      gst_mad_base_init,
      NULL,
      (GClassInitFunc) gst_mad_class_init,
      NULL,
      NULL,
      sizeof (GstMad),
      0,
      (GInstanceInitFunc) gst_mad_init,
    };

    mad_type =
        g_type_register_static (GST_TYPE_ELEMENT, "GstMad", &mad_info, 0);
  }
  GST_DEBUG_CATEGORY_INIT (mad_debug, "mad", 0, "mad mp3 decoding");
  return mad_type;
}

#define GST_TYPE_MAD_LAYER (gst_mad_layer_get_type())
G_GNUC_UNUSED static GType
gst_mad_layer_get_type (void)
{
  static GType mad_layer_type = 0;
  static GEnumValue mad_layer[] = {
    {0, "0", "Unknown"},
    {MAD_LAYER_I, "1", "I"},
    {MAD_LAYER_II, "2", "II"},
    {MAD_LAYER_III, "3", "III"},
    {0, NULL, NULL},
  };

  if (!mad_layer_type) {
    mad_layer_type = g_enum_register_static ("GstMadLayer", mad_layer);
  }
  return mad_layer_type;
}

#define GST_TYPE_MAD_MODE (gst_mad_mode_get_type())
G_GNUC_UNUSED static GType
gst_mad_mode_get_type (void)
{
  static GType mad_mode_type = 0;
  static GEnumValue mad_mode[] = {
    {-1, "-1", "Unknown"},
    {MAD_MODE_SINGLE_CHANNEL, "0", "Single Channel"},
    {MAD_MODE_DUAL_CHANNEL, "1", "Dual Channel"},
    {MAD_MODE_JOINT_STEREO, "2", "Joint Stereo"},
    {MAD_MODE_STEREO, "3", "Stereo"},
    {0, NULL, NULL},
  };

  if (!mad_mode_type) {
    mad_mode_type = g_enum_register_static ("GstMadMode", mad_mode);
  }
  return mad_mode_type;
}

#define GST_TYPE_MAD_EMPHASIS (gst_mad_emphasis_get_type())
G_GNUC_UNUSED static GType
gst_mad_emphasis_get_type (void)
{
  static GType mad_emphasis_type = 0;
  static GEnumValue mad_emphasis[] = {
    {-1, "-1", "Unknown"},
    {MAD_EMPHASIS_NONE, "0", "None"},
    {MAD_EMPHASIS_50_15_US, "1", "50/15 Microseconds"},
    {MAD_EMPHASIS_CCITT_J_17, "2", "CCITT J.17"},
    {MAD_EMPHASIS_RESERVED, "3", "Reserved"},
    {0, NULL, NULL},
  };

  if (!mad_emphasis_type) {
    mad_emphasis_type = g_enum_register_static ("GstMadEmphasis", mad_emphasis);
  }
  return mad_emphasis_type;
}

static void
gst_mad_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 (&mad_sink_template_factory));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&mad_src_template_factory));
  gst_element_class_set_details (element_class, &gst_mad_details);
}
static void
gst_mad_class_init (GstMadClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;

  parent_class = g_type_class_ref (GST_TYPE_ELEMENT);

  gobject_class->set_property = gst_mad_set_property;
  gobject_class->get_property = gst_mad_get_property;
  gobject_class->dispose = gst_mad_dispose;

  gstelement_class->change_state = gst_mad_change_state;
  gstelement_class->set_index = gst_mad_set_index;
  gstelement_class->get_index = gst_mad_get_index;

  /* init properties */
  /* currently, string representations are used, we might want to change that */
  /* FIXME: descriptions need to be more technical,
   * default values and ranges need to be selected right */
  g_object_class_install_property (gobject_class, ARG_HALF,
      g_param_spec_boolean ("half", "Half", "Generate PCM at 1/2 sample rate",
          FALSE, G_PARAM_READWRITE));
  g_object_class_install_property (gobject_class, ARG_IGNORE_CRC,
      g_param_spec_boolean ("ignore_crc", "Ignore CRC", "Ignore CRC errors",
          TRUE, G_PARAM_READWRITE));

  /* register tags */
#define GST_TAG_LAYER    "layer"
#define GST_TAG_MODE     "mode"
#define GST_TAG_EMPHASIS "emphasis"

  gst_tag_register (GST_TAG_LAYER, GST_TAG_FLAG_ENCODED, G_TYPE_UINT,
      "layer", "MPEG audio layer", NULL);
  gst_tag_register (GST_TAG_MODE, GST_TAG_FLAG_ENCODED, G_TYPE_STRING,
      "mode", "MPEG audio channel mode", NULL);
  gst_tag_register (GST_TAG_EMPHASIS, GST_TAG_FLAG_ENCODED, G_TYPE_STRING,
      "emphasis", "MPEG audio emphasis", NULL);
}

static void
gst_mad_init (GstMad * mad)
{
  /* create the sink and src pads */
  mad->sinkpad =
      gst_pad_new_from_template (gst_static_pad_template_get
      (&mad_sink_template_factory), "sink");
  gst_element_add_pad (GST_ELEMENT (mad), mad->sinkpad);
  gst_pad_set_chain_function (mad->sinkpad, GST_DEBUG_FUNCPTR (gst_mad_chain));
  gst_pad_set_convert_function (mad->sinkpad,
      GST_DEBUG_FUNCPTR (gst_mad_convert_sink));
  gst_pad_set_formats_function (mad->sinkpad,
      GST_DEBUG_FUNCPTR (gst_mad_get_formats));

  mad->srcpad =
      gst_pad_new_from_template (gst_static_pad_template_get
      (&mad_src_template_factory), "src");
  gst_element_add_pad (GST_ELEMENT (mad), mad->srcpad);
  gst_pad_set_event_function (mad->srcpad,
      GST_DEBUG_FUNCPTR (gst_mad_src_event));
  gst_pad_set_event_mask_function (mad->srcpad,
      GST_DEBUG_FUNCPTR (gst_mad_get_event_masks));
  gst_pad_set_query_function (mad->srcpad,
      GST_DEBUG_FUNCPTR (gst_mad_src_query));
  gst_pad_set_query_type_function (mad->srcpad,
      GST_DEBUG_FUNCPTR (gst_mad_get_query_types));
  gst_pad_set_convert_function (mad->srcpad,
      GST_DEBUG_FUNCPTR (gst_mad_convert_src));
  gst_pad_set_formats_function (mad->srcpad,
      GST_DEBUG_FUNCPTR (gst_mad_get_formats));
  gst_pad_use_explicit_caps (mad->srcpad);

  mad->tempbuffer = g_malloc (MAD_BUFFER_MDLEN * 3);
  mad->tempsize = 0;
  mad->base_byte_offset = 0;
  mad->bytes_consumed = 0;
  mad->total_samples = 0;
  mad->new_header = TRUE;
  mad->framecount = 0;
  mad->vbr_average = 0;
  mad->vbr_rate = 0;
  mad->restart = FALSE;
  mad->segment_start = 0;
  mad->header.mode = -1;
  mad->header.emphasis = -1;
  mad->tags = NULL;

  mad->half = FALSE;
  mad->ignore_crc = TRUE;
  mad->check_for_xing = TRUE;
  GST_FLAG_SET (mad, GST_ELEMENT_EVENT_AWARE);
}

static void
gst_mad_dispose (GObject * object)
{
  GstMad *mad = GST_MAD (object);

  gst_mad_set_index (GST_ELEMENT (object), NULL);

  G_OBJECT_CLASS (parent_class)->dispose (object);

  g_free (mad->tempbuffer);
}

static void
gst_mad_set_index (GstElement * element, GstIndex * index)
{
  GstMad *mad = GST_MAD (element);

  mad->index = index;

  if (index)
    gst_index_get_writer_id (index, GST_OBJECT (element), &mad->index_id);
}

static GstIndex *
gst_mad_get_index (GstElement * element)
{
  GstMad *mad = GST_MAD (element);

  return mad->index;
}

static const GstFormat *
gst_mad_get_formats (GstPad * pad)
{
  static const GstFormat src_formats[] = {
    GST_FORMAT_BYTES,
    GST_FORMAT_DEFAULT,
    GST_FORMAT_TIME,
    0
  };
  static const GstFormat sink_formats[] = {
    GST_FORMAT_BYTES,
    GST_FORMAT_TIME,
    0
  };

  return (GST_PAD_IS_SRC (pad) ? src_formats : sink_formats);
}

static const GstEventMask *
gst_mad_get_event_masks (GstPad * pad)
{
  static const GstEventMask gst_mad_src_event_masks[] = {
    {GST_EVENT_SEEK, GST_SEEK_METHOD_SET | GST_SEEK_FLAG_FLUSH},
    {0,}
  };

  return gst_mad_src_event_masks;
}

static gboolean
gst_mad_convert_sink (GstPad * pad, GstFormat src_format, gint64 src_value,
    GstFormat * dest_format, gint64 * dest_value)
{
  gboolean res = TRUE;
  GstMad *mad;

  mad = GST_MAD (gst_pad_get_parent (pad));

  if (mad->vbr_average == 0)
    return FALSE;

  switch (src_format) {
    case GST_FORMAT_BYTES:
      switch (*dest_format) {
        case GST_FORMAT_TIME:
          /* multiply by 8 because vbr is in bits/second */
          *dest_value = src_value * 8 * GST_SECOND / mad->vbr_average;
          break;
        default:
          res = FALSE;
      }
      break;
    case GST_FORMAT_TIME:
      switch (*dest_format) {
        case GST_FORMAT_BYTES:
          /* multiply by 8 because vbr is in bits/second */
          *dest_value = src_value * mad->vbr_average / (8 * GST_SECOND);
          break;
        default:
          res = FALSE;
      }
      break;
    default:
      res = FALSE;
  }
  return res;
}

static gboolean
gst_mad_convert_src (GstPad * pad, GstFormat src_format, gint64 src_value,
    GstFormat * dest_format, gint64 * dest_value)
{
  gboolean res = TRUE;
  guint scale = 1;
  gint bytes_per_sample;
  GstMad *mad;

  mad = GST_MAD (gst_pad_get_parent (pad));

  bytes_per_sample = MAD_NCHANNELS (&mad->frame.header) << 1;

  switch (src_format) {
    case GST_FORMAT_BYTES:
      switch (*dest_format) {
        case GST_FORMAT_DEFAULT:
          if (bytes_per_sample == 0)
            return FALSE;
          *dest_value = src_value / bytes_per_sample;
          break;
        case GST_FORMAT_TIME:
        {
          gint byterate = bytes_per_sample * mad->frame.header.samplerate;

          if (byterate == 0)
            return FALSE;
          *dest_value = src_value * GST_SECOND / byterate;
          break;
        }
        default:
          res = FALSE;
      }
      break;
    case GST_FORMAT_DEFAULT:
      switch (*dest_format) {
        case GST_FORMAT_BYTES:
          *dest_value = src_value * bytes_per_sample;
          break;
        case GST_FORMAT_TIME:
          if (mad->frame.header.samplerate == 0)
            return FALSE;
          *dest_value = src_value * GST_SECOND / mad->frame.header.samplerate;
          break;
        default:
          res = FALSE;
      }
      break;
    case GST_FORMAT_TIME:
      switch (*dest_format) {
        case GST_FORMAT_BYTES:
          scale = bytes_per_sample;
          /* fallthrough */
        case GST_FORMAT_DEFAULT:
          *dest_value =
              src_value * scale * mad->frame.header.samplerate / GST_SECOND;
          break;
        default:
          res = FALSE;
      }
      break;
    default:
      res = FALSE;
  }
  return res;
}

static const GstQueryType *
gst_mad_get_query_types (GstPad * pad)
{
  static const GstQueryType gst_mad_src_query_types[] = {
    GST_QUERY_TOTAL,
    GST_QUERY_POSITION,
    0
  };

  return gst_mad_src_query_types;
}

static gboolean
gst_mad_src_query (GstPad * pad, GstQueryType type,
    GstFormat * format, gint64 * value)
{
  gboolean res = TRUE;
  GstMad *mad;

  mad = GST_MAD (gst_pad_get_parent (pad));

  switch (type) {
    case GST_QUERY_TOTAL:
    {
      switch (*format) {
        case GST_FORMAT_BYTES:
        case GST_FORMAT_DEFAULT:
        case GST_FORMAT_TIME:
        {
          gint64 peer_value;
          const GstFormat *peer_formats;

          res = FALSE;

          peer_formats = gst_pad_get_formats (GST_PAD_PEER (mad->sinkpad));

          while (peer_formats && *peer_formats && !res) {

            GstFormat peer_format = *peer_formats;

            /* do the probe */
            if (gst_pad_query (GST_PAD_PEER (mad->sinkpad), GST_QUERY_TOTAL,
                    &peer_format, &peer_value)) {
              GstFormat conv_format;

              /* convert to TIME */
              conv_format = GST_FORMAT_TIME;
              res = gst_pad_convert (mad->sinkpad,
                  peer_format, peer_value, &conv_format, value);
              /* and to final format */
              res &= gst_pad_convert (pad,
                  GST_FORMAT_TIME, *value, format, value);
            }
            peer_formats++;
          }
          break;
        }
        default:
          res = FALSE;
          break;
      }
      break;
    }
    case GST_QUERY_POSITION:
      switch (*format) {
        default:
        {
          /* we only know about our samples, convert to requested format */
          res &= gst_pad_convert (pad,
              GST_FORMAT_DEFAULT, mad->total_samples, format, value);
          break;
        }
      }
      break;
    default:
      res = FALSE;
      break;
  }
  return res;
}

static gboolean
index_seek (GstMad * mad, GstPad * pad, GstEvent * event)
{
  /* since we know the exact byteoffset of the frame,
     make sure to try bytes first */

  const GstFormat try_all_formats[] = {
    GST_FORMAT_BYTES,
    GST_FORMAT_TIME,
    0
  };
  const GstFormat *try_formats = try_all_formats;
  const GstFormat *peer_formats;

  GstIndexEntry *entry = gst_index_get_assoc_entry (mad->index, mad->index_id,
      GST_INDEX_LOOKUP_BEFORE, 0,
      GST_EVENT_SEEK_FORMAT (event),
      GST_EVENT_SEEK_OFFSET (event));

  GST_DEBUG ("index seek");

  if (!entry)
    return FALSE;

  peer_formats = gst_pad_get_formats (GST_PAD_PEER (mad->sinkpad));

  while (gst_formats_contains (peer_formats, *try_formats)) {
    gint64 value;
    GstEvent *seek_event;

    if (gst_index_entry_assoc_map (entry, *try_formats, &value)) {
      /* lookup succeeded, create the seek */

      GST_DEBUG ("index %s %" G_GINT64_FORMAT
          " -> %s %" G_GINT64_FORMAT,
          gst_format_get_details (GST_EVENT_SEEK_FORMAT (event))->nick,
          GST_EVENT_SEEK_OFFSET (event),
          gst_format_get_details (*try_formats)->nick, value);

      seek_event = gst_event_new_seek (*try_formats |
          GST_SEEK_METHOD_SET | GST_SEEK_FLAG_FLUSH, value);

      if (gst_pad_send_event (GST_PAD_PEER (mad->sinkpad), seek_event)) {
        /* seek worked, we're done, loop will exit */
        mad->restart = TRUE;
        g_assert (GST_EVENT_SEEK_FORMAT (event) == GST_FORMAT_TIME);
        mad->segment_start = GST_EVENT_SEEK_OFFSET (event);
        return TRUE;
      }
    }
    try_formats++;
  }

  return FALSE;
}

static gboolean
normal_seek (GstMad * mad, GstPad * pad, GstEvent * event)
{
  gint64 src_offset;
  gboolean flush;
  GstFormat format;
  const GstFormat *peer_formats;
  gboolean res;

  GST_DEBUG ("normal seek");

  format = GST_FORMAT_TIME;

  /* first bring the src_format to TIME */
  if (!gst_pad_convert (pad,
          GST_EVENT_SEEK_FORMAT (event), GST_EVENT_SEEK_OFFSET (event),
          &format, &src_offset)) {
    /* didn't work, probably unsupported seek format then */
    return FALSE;
  }

  GST_DEBUG ("seek to time %" GST_TIME_FORMAT, GST_TIME_ARGS (src_offset));
  /* shave off the flush flag, we'll need it later */
  flush = GST_EVENT_SEEK_FLAGS (event) & GST_SEEK_FLAG_FLUSH;

  /* assume the worst */
  res = FALSE;

  peer_formats = gst_pad_get_formats (GST_PAD_PEER (mad->sinkpad));

  /* while we did not exhaust our seek formats without result */
  while (peer_formats && *peer_formats && !res) {
    gint64 desired_offset;

    format = *peer_formats;

    /* try to convert requested format to one we can seek with on the sinkpad */
    if (gst_pad_convert (mad->sinkpad, GST_FORMAT_TIME, src_offset,
            &format, &desired_offset)) {
      GstEvent *seek_event;

      /* conversion succeeded, create the seek */
      seek_event = gst_event_new_seek (format | GST_SEEK_METHOD_SET | flush,
          desired_offset);
      /* do the seek */
      if (gst_pad_send_event (GST_PAD_PEER (mad->sinkpad), seek_event)) {
        /* seek worked, we're done, loop will exit */
        res = TRUE;
      }
    }
    /* at this point, either the seek worked or res == FALSE */
    if (res)
      /* we need to break out of the processing loop on flush */
      mad->restart = flush;

    peer_formats++;
  }

  return res;
}

static gboolean
gst_mad_src_event (GstPad * pad, GstEvent * event)
{
  gboolean res = TRUE;
  GstMad *mad;

  mad = GST_MAD (gst_pad_get_parent (pad));

  switch (GST_EVENT_TYPE (event)) {
    case GST_EVENT_SEEK_SEGMENT:
      GST_DEBUG ("forwarding seek event to sink pad");
      gst_event_ref (event);
      if (gst_pad_send_event (GST_PAD_PEER (mad->sinkpad), event)) {
        /* seek worked, we're done, loop will exit */
        res = TRUE;
      }
      break;
      /* the all-formats seek logic */
    case GST_EVENT_SEEK:
      if (mad->index)
        res = index_seek (mad, pad, event);
      else
        res = normal_seek (mad, pad, event);
      break;

    default:
      res = FALSE;
      break;
  }

  gst_event_unref (event);
  return res;
}

static inline signed int
scale (mad_fixed_t sample)
{
  /* round */
  sample += (1L << (MAD_F_FRACBITS - 16));

  /* clip */
  if (sample >= MAD_F_ONE)
    sample = MAD_F_ONE - 1;
  else if (sample < -MAD_F_ONE)
    sample = -MAD_F_ONE;

  /* quantize */
  return sample >> (MAD_F_FRACBITS + 1 - 16);
}

/* do we need this function? */
static void
gst_mad_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstMad *mad;

  g_return_if_fail (GST_IS_MAD (object));

  mad = GST_MAD (object);

  switch (prop_id) {
    case ARG_HALF:
      mad->half = g_value_get_boolean (value);
      break;
    case ARG_IGNORE_CRC:
      mad->ignore_crc = g_value_get_boolean (value);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}
static void
gst_mad_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  GstMad *mad;

  g_return_if_fail (GST_IS_MAD (object));

  mad = GST_MAD (object);

  switch (prop_id) {
    case ARG_HALF:
      g_value_set_boolean (value, mad->half);
      break;
    case ARG_IGNORE_CRC:
      g_value_set_boolean (value, mad->ignore_crc);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_mad_update_info (GstMad * mad)
{
  gint abr = mad->vbr_average;
  struct mad_header *header = &mad->frame.header;
  gboolean changed = FALSE;

#define CHECK_HEADER(h1,str)					\
G_STMT_START{							\
  if (mad->header.h1 != header->h1 || mad->new_header) {	\
    mad->header.h1 = header->h1;				\
     changed = TRUE;						\
  };								\
} G_STMT_END

  /* update average bitrate */
  if (mad->new_header) {
    mad->framecount = 1;
    mad->vbr_rate = header->bitrate;
    abr = 0;
  } else {
    mad->framecount++;
    mad->vbr_rate += header->bitrate;
  }
  mad->vbr_average = (gint) (mad->vbr_rate / mad->framecount);

  CHECK_HEADER (layer, "layer");
  CHECK_HEADER (mode, "mode");
  CHECK_HEADER (emphasis, "emphasis");

  if (header->bitrate != mad->header.bitrate || mad->new_header) {
    mad->header.bitrate = header->bitrate;
  }
  mad->new_header = FALSE;

  if (changed) {
    GstTagList *list;
    GEnumValue *mode;
    GEnumValue *emphasis;

    mode =
        g_enum_get_value (g_type_class_ref (GST_TYPE_MAD_MODE),
        mad->header.mode);
    emphasis =
        g_enum_get_value (g_type_class_ref (GST_TYPE_MAD_EMPHASIS),
        mad->header.emphasis);
    list = gst_tag_list_new ();
    gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
        GST_TAG_LAYER, mad->header.layer,
        GST_TAG_MODE, mode->value_nick,
        GST_TAG_EMPHASIS, emphasis->value_nick, NULL);
    gst_element_found_tags (GST_ELEMENT (mad), list);
    gst_tag_list_free (list);
  }
#undef CHECK_HEADER

}

static void
gst_mad_handle_event (GstPad * pad, GstBuffer * buffer)
{
  GstEvent *event = GST_EVENT (buffer);
  GstMad *mad = GST_MAD (gst_pad_get_parent (pad));

  GST_DEBUG ("handling event %d", GST_EVENT_TYPE (event));
  switch (GST_EVENT_TYPE (event)) {
    case GST_EVENT_DISCONTINUOUS:
    {
      gint n = GST_EVENT_DISCONT_OFFSET_LEN (event);
      gint i;

      mad->total_samples = 0;

      for (i = 0; i < n; i++) {
        const GstFormat *formats;

        formats = gst_pad_get_formats (pad);

        if (gst_formats_contains (formats, GST_EVENT_DISCONT_OFFSET (event,
                    i).format)) {
          gint64 value = GST_EVENT_DISCONT_OFFSET (event, i).value;
          gint64 time;
          GstFormat format;
          GstEvent *discont;

          /* see how long the input bytes take */
          if (GST_EVENT_DISCONT_OFFSET (event, i).format != GST_FORMAT_TIME) {
            format = GST_FORMAT_TIME;
            if (!gst_pad_convert (pad,
                    GST_EVENT_DISCONT_OFFSET (event, i).format,
                    value, &format, &time)) {
              continue;
            }
          } else {
            time = value;
          }

          /* for now, this is the best we can do to get the total number
           * of samples. This is suboptimal because the incoming event
           * might contain this information already (although I believe
           * that this doesn't happen anywhere so far). */
          format = GST_FORMAT_DEFAULT;
          if (!gst_pad_convert (mad->srcpad,
                  GST_FORMAT_TIME, time, &format, &mad->total_samples)) {
            continue;
          }

          if (GST_PAD_IS_USABLE (mad->srcpad)) {
            discont = gst_event_new_discontinuous (FALSE, GST_FORMAT_TIME,
                time, NULL);
            gst_pad_push (mad->srcpad, GST_DATA (discont));
          }
          gst_event_unref (event);
          goto done;
        }
      }
      GST_WARNING ("Failed to retrieve sample position");
      /* this isn't really correct? */
      gst_pad_event_default (pad, event);
    done:
      mad->tempsize = 0;
      /* we don't need to restart when we get here */
      mad->restart = FALSE;
      break;
    }
    case GST_EVENT_EOS:
      mad->caps_set = FALSE;    /* could be a new stream */
      gst_pad_event_default (pad, event);
      break;
    default:
      gst_pad_event_default (pad, event);
      break;
  }
}

static gboolean
gst_mad_check_restart (GstMad * mad)
{
  gboolean yes = mad->restart;

  if (mad->restart) {
    mad->restart = FALSE;
    mad->tempsize = 0;
  }
  return yes;
}


/* The following code has been taken from 
 * rhythmbox/metadata/monkey-media/stream-info-impl/id3-vfs/mp3bitrate.c
 * which took it from xine-lib/src/demuxers/demux_mpgaudio.c
 * This code has been kindly relicensed to LGPL by Thibaut Mattern and 
 * Bastien Nocera
 */
#define BE_32(x) GINT32_FROM_BE(*(gint*)(x))

#define FOURCC_TAG( ch0, ch1, ch2, ch3 )		\
	( (long)(unsigned char)(ch3) |			\
	  ( (long)(unsigned char)(ch2) << 8 ) |		\
	  ( (long)(unsigned char)(ch1) << 16 ) |	\
	  ( (long)(unsigned char)(ch0) << 24 ) )

/* Xing header stuff */
#define XING_TAG FOURCC_TAG('X', 'i', 'n', 'g')
#define XING_FRAMES_FLAG     0x0001
#define XING_BYTES_FLAG      0x0002
#define XING_TOC_FLAG        0x0004
#define XING_VBR_SCALE_FLAG  0x0008
#define XING_TOC_LENGTH      100

/* check for valid "Xing" VBR header */
static int
is_xhead (unsigned char *buf)
{
  return (BE_32 (buf) == XING_TAG);
}


#undef LOG
//#define LOG
#ifdef LOG
#define lprintf(x...) g_print(x)
#else
#define lprintf(x...)
#endif

static int
mpg123_parse_xing_header (struct mad_header *header,
    const guint8 * buf, int bufsize, int *bitrate, int *time)
{
  int i;
  guint8 *ptr = (guint8 *) buf;
  double frame_duration;
  int xflags, xframes, xbytes, xvbr_scale;
  int abr;
  guint8 xtoc[XING_TOC_LENGTH];

  /* This should be the MPEG Audio version ID 
   * (version 2.5, 2 or 1) least significant byte, but mad doesn't 
   * provide that, so assume it's always MPEG 1
   */
  int lsf_bit = 1;

  xframes = xbytes = 0;

  /* offset of the Xing header */
  if (lsf_bit) {
    if (header->mode != MAD_MODE_STEREO)
      ptr += (32 + 4);
    else
      ptr += (17 + 4);
  } else {
    if (header->mode != MAD_MODE_STEREO)
      ptr += (17 + 4);
    else
      ptr += (9 + 4);
  }

  if (ptr >= (buf + bufsize - 4))
    return 0;

  if (is_xhead (ptr)) {
    lprintf ("Xing header found\n");

    ptr += 4;
    if (ptr >= (buf + bufsize - 4))
      return 0;

    xflags = BE_32 (ptr);
    ptr += 4;

    if (xflags & XING_FRAMES_FLAG) {
      if (ptr >= (buf + bufsize - 4))
        return 0;
      xframes = BE_32 (ptr);
      lprintf ("xframes: %d\n", xframes);
      ptr += 4;
    }
    if (xflags & XING_BYTES_FLAG) {
      if (ptr >= (buf + bufsize - 4))
        return 0;
      xbytes = BE_32 (ptr);
      lprintf ("xbytes: %d\n", xbytes);
      ptr += 4;
    }
    if (xflags & XING_TOC_FLAG) {
      lprintf ("toc found\n");
      if (ptr >= (buf + bufsize - XING_TOC_LENGTH))
        return 0;
      for (i = 0; i < XING_TOC_LENGTH; i++) {
        xtoc[i] = *(ptr + i);
        lprintf ("%d ", xtoc[i]);
      }
      lprintf ("\n");
      ptr += XING_TOC_LENGTH;
    }

    xvbr_scale = -1;
    if (xflags & XING_VBR_SCALE_FLAG) {
      if (ptr >= (buf + bufsize - 4))
        return 0;
      xvbr_scale = BE_32 (ptr);
      lprintf ("xvbr_scale: %d\n", xvbr_scale);
    }

    /* 1 kbit = 1000 bits ! (and not 1024 bits) */
    if (xflags & (XING_FRAMES_FLAG | XING_BYTES_FLAG)) {
      if (header->layer == MAD_LAYER_I) {
        frame_duration = 384.0 / (double) header->samplerate;
      } else {
        int slots_per_frame;

        slots_per_frame = ((header->layer == MAD_LAYER_III)
            && !lsf_bit) ? 72 : 144;
        frame_duration = slots_per_frame * 8.0 / (double) header->samplerate;
      }
      abr = ((double) xbytes * 8.0) / ((double) xframes * frame_duration);
      lprintf ("abr: %d bps\n", abr);
      if (bitrate != NULL) {
        *bitrate = abr;
      }
      if (time != NULL) {
        *time = (double) xframes *frame_duration;

        lprintf ("stream_length: %d s, %d min %d s\n", *time,
            *time / 60, *time % 60);
      }
    } else {
      /* it's a stupid Xing header */
      lprintf ("not a Xing VBR file\n");
    }
    return 1;
  } else {
    lprintf ("Xing header not found\n");
    return 0;
  }
}

/* End of Xine code */

/* internal function to check if the header has changed and thus the
 * caps need to be reset.  Only call during normal mode, not resyncing */
static void
gst_mad_check_caps_reset (GstMad * mad)
{
  guint nchannels;
  guint rate;

  nchannels = MAD_NCHANNELS (&mad->frame.header);

#if MAD_VERSION_MINOR <= 12
  rate = mad->header.sfreq;
#else
  rate = mad->frame.header.samplerate;
#endif

  /* rate and channels are not supposed to change in a continuous stream,
   * so check this first before doing anything */

  /* only set caps if they weren't already set for this continuous stream */
  if (mad->channels != nchannels || mad->rate != rate) {
    if (mad->caps_set) {
      GST_DEBUG
          ("Header changed from %d Hz/%d ch to %d Hz/%d ch, failed sync after seek ?",
          mad->rate, mad->channels, rate, nchannels);
      return;
    }
  }
  gst_mad_update_info (mad);

  if (mad->channels != nchannels || mad->rate != rate) {
    GstCaps *caps;

    if (mad->stream.options & MAD_OPTION_HALFSAMPLERATE)
      rate >>= 1;

    /* we set the caps even when the pad is not connected so they
     * can be gotten for streaminfo */
    caps = gst_caps_new_simple ("audio/x-raw-int",
        "endianness", G_TYPE_INT, G_BYTE_ORDER,
        "signed", G_TYPE_BOOLEAN, TRUE,
        "width", G_TYPE_INT, 16,
        "depth", G_TYPE_INT, 16,
        "rate", G_TYPE_INT, rate, "channels", G_TYPE_INT, nchannels, NULL);

    gst_pad_set_explicit_caps (mad->srcpad, caps);
    gst_caps_free (caps);
    mad->caps_set = TRUE;       /* set back to FALSE on discont */
    mad->channels = nchannels;
    mad->rate = rate;
  }
}

static void
gst_mad_chain (GstPad * pad, GstData * _data)
{
  GstBuffer *buffer = GST_BUFFER (_data);
  GstMad *mad;
  gchar *data;
  glong size;
  gboolean new_pts = FALSE;
  GstClockTime timestamp;

  mad = GST_MAD (gst_pad_get_parent (pad));
  g_return_if_fail (GST_IS_MAD (mad));

  /* handle events */
  if (GST_IS_EVENT (buffer)) {
    gst_mad_handle_event (pad, buffer);
    return;
  }

  /* restarts happen on discontinuities, ie. seek, flush, PAUSED to PLAYING */
  if (gst_mad_check_restart (mad))
    GST_DEBUG ("mad restarted");

  timestamp = GST_BUFFER_TIMESTAMP (buffer);

  /* handle timestamps */
  if (GST_CLOCK_TIME_IS_VALID (timestamp)) {
    /* if there is nothing left to process in our temporary buffer,
     * we can set this timestamp on the next outgoing buffer */
    if (mad->tempsize == 0) {
      /* we have to save the result here because we can't yet convert
       * the timestamp to a sample offset yet,
       * the samplerate might not be known yet */
      mad->last_ts = timestamp;
      mad->base_byte_offset = GST_BUFFER_OFFSET (buffer);
      mad->bytes_consumed = 0;
    }
    /* else we need to finish the current partial frame with the old timestamp
     * and queue this timestamp for the next frame */
    else {
      new_pts = TRUE;
    }
  }

  /* handle data */
  data = GST_BUFFER_DATA (buffer);
  size = GST_BUFFER_SIZE (buffer);

  /* process the incoming buffer in chunks of maximum MAD_BUFFER_MDLEN bytes;
   * this is the upper limit on processable chunk sizes set by mad */
  while (size > 0) {
    gint tocopy;
    guchar *mad_input_buffer;   /* convenience pointer to tempbuffer */

    tocopy = MIN (MAD_BUFFER_MDLEN, size);

    /* append the chunk to process to our internal temporary buffer */
    GST_LOG ("tempbuffer size %d, copying %d bytes from incoming buffer",
        mad->tempsize, tocopy);
    memcpy (mad->tempbuffer + mad->tempsize, data, tocopy);
    mad->tempsize += tocopy;

    /* update our incoming buffer's parameters to reflect this */
    size -= tocopy;
    data += tocopy;

    mad_input_buffer = mad->tempbuffer;

    /* while we have data we can consume it */
    while (mad->tempsize >= 0) {
      gint consumed = 0;
      guint nsamples;
      guint64 time_offset;
      guint64 time_duration;
      unsigned char const *before_sync, *after_sync;

      mad->in_error = FALSE;
      mad_stream_buffer (&mad->stream, mad_input_buffer, mad->tempsize);

      if (mad_frame_decode (&mad->frame, &mad->stream) == -1) {
        /* not enough data, need to wait for next buffer? */
        if (mad->stream.error == MAD_ERROR_BUFLEN) {
          GST_LOG ("not enough data in tempbuffer (%d), breaking to get more",
              mad->tempsize);
          break;
        }
        /* we are in an error state */
        mad->in_error = TRUE;
        GST_DEBUG ("mad_frame_decode had an error: %s",
            mad_stream_errorstr (&mad->stream));
        if (!MAD_RECOVERABLE (mad->stream.error)) {
          GST_ELEMENT_ERROR (mad, STREAM, DECODE, (NULL), (NULL));
          return;
        } else if (mad->stream.error == MAD_ERROR_LOSTSYNC) {
          /* lost sync, force a resync */
          signed long tagsize;

          GST_INFO ("recoverable lost sync error");

          tagsize = id3_tag_query (mad->stream.this_frame,
              mad->stream.bufend - mad->stream.this_frame);

          if (tagsize > mad->tempsize) {
            GST_INFO ("mad: got partial id3 tag in buffer, skipping");
          } else if (tagsize > 0) {
            struct id3_tag *tag;
            id3_byte_t const *data;

            GST_INFO ("mad: got ID3 tag size %ld", tagsize);

            data = mad->stream.this_frame;

            /* mad has moved the pointer to the next frame over the start of the
             * id3 tags, so we need to flush one byte less than the tagsize */
            mad_stream_skip (&mad->stream, tagsize - 1);

            tag = id3_tag_parse (data, tagsize);
            if (tag) {
              GstTagList *list;

              list = gst_mad_id3_to_tag_list (tag);
              id3_tag_delete (tag);
              GST_DEBUG ("found tag");
              gst_element_found_tags (GST_ELEMENT (mad), list);
              if (mad->tags) {
                gst_tag_list_insert (mad->tags, list, GST_TAG_MERGE_PREPEND);
              } else {
                mad->tags = gst_tag_list_copy (list);
              }
              if (GST_PAD_IS_USABLE (mad->srcpad)) {
                gst_pad_push (mad->srcpad, GST_DATA (gst_event_new_tag (list)));
              } else {
                gst_tag_list_free (list);
              }
            }
          }
        }

        mad_frame_mute (&mad->frame);
        mad_synth_mute (&mad->synth);
        before_sync = mad->stream.ptr.byte;
        if (mad_stream_sync (&mad->stream) != 0)
          GST_WARNING ("mad_stream_sync failed");
        after_sync = mad->stream.ptr.byte;
        /* a succesful resync should make us drop bytes as consumed, so
           calculate from the byte pointers before and after resync */
        consumed = after_sync - before_sync;
        GST_DEBUG ("resynchronization consumes %d bytes", consumed);
        GST_DEBUG ("synced to data: 0x%0x 0x%0x", *mad->stream.ptr.byte,
            *(mad->stream.ptr.byte + 1));


        mad_stream_sync (&mad->stream);
        /* recoverable errors pass */
        goto next;
      }

      if (mad->check_for_xing) {
        int bitrate, time;
        GstTagList *list;
        int frame_len = mad->stream.next_frame - mad->stream.this_frame;

        /* Assume Xing headers can only be the first frame in a mp3 file */
        if (mpg123_parse_xing_header (&mad->frame.header,
                mad->stream.this_frame, frame_len, &bitrate, &time)) {
          list = gst_tag_list_new ();
          gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
              GST_TAG_DURATION, (gint64) time * 1000 * 1000 * 1000,
              GST_TAG_BITRATE, bitrate, NULL);
          gst_element_found_tags (GST_ELEMENT (mad), list);
          if (GST_PAD_IS_USABLE (mad->srcpad)) {
            gst_pad_push (mad->srcpad, GST_DATA (gst_event_new_tag (list)));
          } else {
            gst_tag_list_free (list);
          }
        }

        mad->check_for_xing = FALSE;
        goto next;
      }

      /* if we're not resyncing/in error, check if caps need to be set again */
      if (!mad->in_error)
        gst_mad_check_caps_reset (mad);
      nsamples = MAD_NSBSAMPLES (&mad->frame.header) *
          (mad->stream.options & MAD_OPTION_HALFSAMPLERATE ? 16 : 32);

      if (mad->frame.header.samplerate == 0) {
        g_warning
            ("mad->frame.header.samplerate is 0; timestamps cannot be calculated");
        time_offset = GST_CLOCK_TIME_NONE;
        time_duration = GST_CLOCK_TIME_NONE;
      } else {
        /* if we have a pending timestamp, we can use it now to calculate the sample offset */
        if (GST_CLOCK_TIME_IS_VALID (mad->last_ts)) {
          GstFormat format = GST_FORMAT_DEFAULT;

          gst_pad_convert (mad->srcpad, GST_FORMAT_TIME, mad->last_ts, &format,
              &mad->total_samples);
          mad->last_ts = GST_CLOCK_TIME_NONE;
        }
        time_offset = mad->total_samples * GST_SECOND
            / mad->frame.header.samplerate;
        time_duration = (nsamples * GST_SECOND / mad->frame.header.samplerate);
      }

      if (mad->index) {
        guint64 x_bytes = mad->base_byte_offset + mad->bytes_consumed;

        gst_index_add_association (mad->index, mad->index_id, 0,
            GST_FORMAT_BYTES, x_bytes, GST_FORMAT_TIME, time_offset, NULL);
      }

      if (GST_PAD_IS_USABLE (mad->srcpad) &&
          mad->segment_start <= (time_offset ==
              GST_CLOCK_TIME_NONE ? 0 : time_offset)) {

        /* for sample accurate seeking, calculate how many samples
           to skip and send the remaining pcm samples */

        GstBuffer *outbuffer;
        gint16 *outdata;
        mad_fixed_t const *left_ch, *right_ch;

        mad_synth_frame (&mad->synth, &mad->frame);
        left_ch = mad->synth.pcm.samples[0];
        right_ch = mad->synth.pcm.samples[1];

        outbuffer = gst_buffer_new_and_alloc (nsamples * mad->channels * 2);
        outdata = (gint16 *) GST_BUFFER_DATA (outbuffer);

        GST_BUFFER_TIMESTAMP (outbuffer) = time_offset;
        GST_BUFFER_DURATION (outbuffer) = time_duration;
        GST_BUFFER_OFFSET (outbuffer) = mad->total_samples;

        /* output sample(s) in 16-bit signed native-endian PCM */
        if (mad->channels == 1) {
          gint count = nsamples;

          while (count--) {
            *outdata++ = scale (*left_ch++) & 0xffff;
          }
        } else {
          gint count = nsamples;

          while (count--) {
            *outdata++ = scale (*left_ch++) & 0xffff;
            *outdata++ = scale (*right_ch++) & 0xffff;
          }
        }

        gst_pad_push (mad->srcpad, GST_DATA (outbuffer));
      }

      mad->total_samples += nsamples;

      /* we have a queued timestamp on the incoming buffer that we should
       * use for the next frame */
      if (new_pts) {
        mad->last_ts = timestamp;
        new_pts = FALSE;
        mad->base_byte_offset = GST_BUFFER_OFFSET (buffer);
        mad->bytes_consumed = 0;
      }

      if (gst_mad_check_restart (mad)) {
        goto end;
      }

    next:
      /* figure out how many bytes mad consumed */
      /* if consumed is already set, it's from the resync higher up, so
         we need to use that value instead.  Otherwise, recalculate from
         mad's consumption */
      if (consumed == 0)
        consumed = mad->stream.next_frame - mad_input_buffer;

      GST_LOG ("mad consumed %d bytes", consumed);
      /* move out pointer to where mad want the next data */
      mad_input_buffer += consumed;
      mad->tempsize -= consumed;
      mad->bytes_consumed += consumed;
    }
    /* we only get here from breaks, tempsize never actually drops below 0 */
    memmove (mad->tempbuffer, mad_input_buffer, mad->tempsize);
  }

end:
  gst_buffer_unref (buffer);
}

static GstElementStateReturn
gst_mad_change_state (GstElement * element)
{
  GstMad *mad;

  mad = GST_MAD (element);

  switch (GST_STATE_TRANSITION (element)) {
    case GST_STATE_NULL_TO_READY:
      break;
    case GST_STATE_READY_TO_PAUSED:
    {
      guint options = 0;

      mad_stream_init (&mad->stream);
      mad_frame_init (&mad->frame);
      mad_synth_init (&mad->synth);
      mad->tempsize = 0;
      mad->total_samples = 0;
      mad->rate = 0;
      mad->channels = 0;
      mad->caps_set = FALSE;
      mad->vbr_average = 0;
      mad->segment_start = 0;
      mad->new_header = TRUE;
      mad->framecount = 0;
      mad->vbr_rate = 0;
      mad->frame.header.samplerate = 0;
      mad->last_ts = GST_CLOCK_TIME_NONE;
      if (mad->ignore_crc)
        options |= MAD_OPTION_IGNORECRC;
      if (mad->half)
        options |= MAD_OPTION_HALFSAMPLERATE;
      mad_stream_options (&mad->stream, options);
      break;
    }
    case GST_STATE_PAUSED_TO_PLAYING:
      /* do something to get out of the chain function faster */
      break;
    case GST_STATE_PLAYING_TO_PAUSED:
      break;
    case GST_STATE_PAUSED_TO_READY:
      mad_synth_finish (&mad->synth);
      mad_frame_finish (&mad->frame);
      mad_stream_finish (&mad->stream);
      mad->restart = TRUE;
      if (mad->tags) {
        gst_tag_list_free (mad->tags);
        mad->tags = NULL;
      }
      break;
    case GST_STATE_READY_TO_NULL:
      break;
  }

  return parent_class->change_state (element);
}