gstreamer/gst/real/gstreal.c

/* RealVideo wrapper plugin
 *
 * Copyright (C) 2005 Lutz Mueller <lutz@topfrose.de>
 * 
 * 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.
 */

#include <config.h>

#include <gst/gstelement.h>
#include <gst/gsterror.h>
#include <gst/gstinfo.h>
#include <gst/gstplugin.h>
#include <gst/gstutils.h>
#include <gst/gstversion.h>

#include <gst/base/gstadapter.h>

#include <dlfcn.h>
#include <string.h>

#define GST_TYPE_REAL_DEC            (gst_realdec_get_type())
#define GST_REAL_DEC(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_REAL_DEC,GstRealDec))
#define GST_REAL_DEC_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_REAL_DEC,GstRealDecClass))

GST_DEBUG_CATEGORY_STATIC (realdec_debug);
#define GST_CAT_DEFAULT realdec_debug

typedef struct _GstRealDec GstRealDec;
typedef struct _GstRealDecClass GstRealDecClass;

static GstElementDetails realdec_details =
GST_ELEMENT_DETAILS ("RealVideo decoder",
    "Codec/Decoder", "Decoder for RealVideo streams",
    "Lutz Mueller <lutz@topfrose.de>");

static GstStaticPadTemplate snk_t =
GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("video/x-pn-realvideo, " "rmversion = (int) [ 2, 4 ]"));
static GstStaticPadTemplate src_t =
GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("video/x-raw-yuv, "
        "format = (fourcc) I420, "
        "framerate = (fraction) [0/1, MAX], "
        "width = (int) [ 16, 4096 ], " "height = (int) [ 16, 4096 ] "));

#define DEFAULT_PATH_RV20 "/usr/lib/win32/drv2.so.6.0"
#define DEFAULT_PATH_RV30 "/usr/lib/win32/drv3.so.6.0"
#define DEFAULT_PATH_RV40 "/usr/lib/win32/drv4.so.6.0"

enum
{
  PROP_0,
  PROP_PATH_RV20,
  PROP_PATH_RV30,
  PROP_PATH_RV40
};

typedef enum
{
  GST_REAL_DEC_VERSION_2 = 2,
  GST_REAL_DEC_VERSION_3 = 3,
  GST_REAL_DEC_VERSION_4 = 4
} GstRealDecVersion;

struct _GstRealDec
{
  GstElement parent;

  GstPad *src, *snk;

  /* Caps */
  GstRealDecVersion version;
  guint width, height;
  gint format, subformat;
  gint framerate_num, framerate_denom;

  /* Variables needed for fixing timestamps. */
  GstClockTime next_ts, last_ts;
  guint16 next_seq, last_seq;

  /* Hooks */
  gpointer handle;
    guint32 (*custom_message) (guint32 *, gpointer);
    guint32 (*free) (gpointer);
    guint32 (*init) (gpointer, gpointer);
    guint32 (*transform) (gchar *, gchar *, guint32 *, guint32 *, gpointer);

  /* Used by the REAL library. */
  gpointer context;

  /* State */
  GstAdapter *adapter;
  guint8 seqnum, subseq;
  guint16 length;
  guint32 fragment_count;
  guint32 fragments[256];

  /* Properties */
  gchar *path_rv20, *path_rv30, *path_rv40;
};

struct _GstRealDecClass
{
  GstElementClass parent_class;
};

GST_BOILERPLATE (GstRealDec, gst_realdec, GstElement, GST_TYPE_ELEMENT);

static GstFlowReturn
gst_realdec_alloc_buffer (GstRealDec * dec, GstClockTime timestamp,
    GstBuffer ** buf)
{
  GstFlowReturn ret;
  const guint8 *b;
  guint8 frame_type;
  guint16 seq;
  GstClockTime ts = timestamp;

  GST_LOG_OBJECT (dec, "timestamp %" GST_TIME_FORMAT, GST_TIME_ARGS (ts));

  /* Fix timestamp. */
  b = gst_adapter_peek (dec->adapter, 4);
  switch (dec->version) {
    case GST_REAL_DEC_VERSION_2:
    {

      /*
       * Bit  1- 2: frame type
       * Bit  3- 9: ?
       * Bit 10-22: sequence number
       * Bit 23-32: ?
       */
      frame_type = (b[0] >> 6) & 0x03;
      seq = ((b[1] & 0x7f) << 6) + ((b[2] & 0xfc) >> 2);
      break;
    }
    case GST_REAL_DEC_VERSION_3:
    {
      /*
       * Bit  1- 2: ?
       * Bit     3: skip packet if 1
       * Bit  4- 5: frame type
       * Bit  6-12: ?
       * Bit 13-25: sequence number
       * Bit 26-32: ?
       */
      frame_type = (b[0] >> 3) & 0x03;
      seq = ((b[1] & 0x0f) << 9) + (b[2] << 1) + ((b[3] & 0x80) >> 7);
      break;
    }
    case GST_REAL_DEC_VERSION_4:
    {
      /*
       * Bit     1: skip packet if 1
       * Bit  2- 3: frame type
       * Bit  4-13: ?
       * Bit 14-26: sequence number
       * Bit 27-32: ?
       */
      frame_type = (b[0] >> 5) & 0x03;
      seq = ((b[1] & 0x07) << 10) + (b[2] << 2) + ((b[3] & 0xc0) >> 6);
      break;
    }
    default:
      goto unknown_version;
  }

  GST_LOG_OBJECT (dec, "frame_type:%d", frame_type);

  switch (frame_type) {
    case 0:
    case 1:
    {
      /* I frame */
      timestamp = dec->next_ts;
      dec->last_ts = dec->next_ts;
      dec->next_ts = ts;
      dec->last_seq = dec->next_seq;
      dec->next_seq = seq;

      break;
    }
    case 2:
    {
      /* P frame */
      timestamp = dec->last_ts = dec->next_ts;
      if (seq < dec->next_seq)
        dec->next_ts += (seq + 0x2000 - dec->next_seq) * GST_MSECOND;
      else
        dec->next_ts += (seq - dec->next_seq) * GST_MSECOND;
      dec->last_seq = dec->next_seq;
      dec->next_seq = seq;
      break;
    }
    case 3:
    {
      /* B frame */
      if (seq < dec->last_seq) {
        timestamp = (seq + 0x2000 - dec->last_seq) * GST_MSECOND + dec->last_ts;
      } else {
        timestamp = (seq - dec->last_seq) * GST_MSECOND + dec->last_ts;
      }

      break;
    }
    default:
      goto unknown_frame_type;
  }

  ret = gst_pad_alloc_buffer (dec->src, GST_BUFFER_OFFSET_NONE,
      dec->width * dec->height * 3 / 2, GST_PAD_CAPS (dec->src), buf);

  if (ret == GST_FLOW_OK)
    GST_BUFFER_TIMESTAMP (*buf) = timestamp;

  return ret;

  /* Errors */
unknown_version:
  {
    GST_ELEMENT_ERROR (dec, STREAM, DECODE,
        ("Unknown version: %i.", dec->version), (NULL));
    return GST_FLOW_ERROR;
  }

unknown_frame_type:
  {
    GST_ELEMENT_ERROR (dec, STREAM, DECODE, ("Unknown frame type."), (NULL));
    return GST_FLOW_ERROR;
  }
}

static GstFlowReturn
gst_realdec_decode (GstRealDec * dec, GstBuffer * in, guint offset)
{
  guint32 result;
  GstBuffer *out = NULL;
  GstFlowReturn ret;
  guint8 *data, hdr_subseq, hdr_seqnum;
  guint32 hdr_offset, hdr_length;
  guint16 n;
  gboolean bres;
  guint8 *buf = GST_BUFFER_DATA (in) + offset;
  guint len = GST_BUFFER_SIZE (in) - offset;
  GstClockTime timestamp = GST_BUFFER_TIMESTAMP (in);

  GST_LOG_OBJECT (dec,
      "Got buffer %p with timestamp %" GST_TIME_FORMAT " offset %d", in,
      GST_TIME_ARGS (timestamp), offset);

  /* Subsequence */
  if (len < 1)
    goto not_enough_data;
  if (*buf != 0x40 && *buf != 0x41 && *buf != 0x42 &&
      *buf != 0x43 && *buf != 0x44 && *buf != 0x45) {
    hdr_subseq = *buf & 0x7f;
    buf++;
    len--;
    if (hdr_subseq == 64)
      hdr_subseq = 1;
  } else {
    hdr_subseq = 1;
  }

  /* Length */
  if (len < 2)
    goto not_enough_data;
  hdr_length = GST_READ_UINT16_BE (buf);
  if (!(hdr_length & 0xc000)) {
    if (len < 4)
      goto not_enough_data;
    hdr_length = GST_READ_UINT32_BE (buf);
    buf += 4;
    len -= 4;
  } else {
    hdr_length &= 0x3fff;
    buf += 2;
    len -= 2;
  }

  /* Offset */
  if (len < 2)
    goto not_enough_data;
  hdr_offset = GST_READ_UINT16_BE (buf);
  if (!(hdr_offset & 0xc000)) {
    if (len < 4)
      goto not_enough_data;
    hdr_offset = GST_READ_UINT32_BE (buf);
    buf += 4;
    len -= 4;
  } else {
    hdr_offset &= 0x3fff;
    buf += 2;
    len -= 2;
  }

  /* Sequence number */
  if (len < 1)
    goto not_enough_data;
  hdr_seqnum = *buf;
  buf++;
  len--;
  if (len < 1)
    goto not_enough_data;

  /* Verify the sequence numbers. */
  if (hdr_subseq == 1) {
    n = gst_adapter_available_fast (dec->adapter);
    if (n > 0) {
      GST_DEBUG_OBJECT (dec, "Dropping data for sequence %i "
          "because we are already receiving data for sequence %i.",
          dec->seqnum, hdr_seqnum);
      gst_adapter_clear (dec->adapter);
    }
    dec->seqnum = hdr_seqnum;
    dec->length = hdr_length;
    dec->fragment_count = 1;
  } else {
    if (dec->seqnum != hdr_seqnum) {
      GST_DEBUG_OBJECT (dec, "Expected sequence %i, got sequence %i "
          "(subseq=%i). Dropping packet.", dec->seqnum, hdr_seqnum, hdr_subseq);
      return GST_FLOW_OK;
    } else if (dec->subseq + 1 != hdr_subseq) {
      GST_DEBUG_OBJECT (dec, "Expected subsequence %i, got subseqence %i. "
          "Dropping packet.", dec->subseq + 1, hdr_subseq);
      return GST_FLOW_OK;
    }
    dec->fragment_count++;
  }
  dec->subseq = hdr_subseq;

  /* Remember the offset */
  if (sizeof (dec->fragments) < 2 * (dec->fragment_count - 1) + 1)
    goto too_many_fragments;
  dec->fragments[2 * (dec->fragment_count - 1)] = 1;
  dec->fragments[2 * (dec->fragment_count - 1) + 1] =
      gst_adapter_available (dec->adapter);

  /* Some buffers need to be skipped. */
  if (((dec->version == GST_REAL_DEC_VERSION_3) && (*buf & 0x20)) ||
      ((dec->version == GST_REAL_DEC_VERSION_4) && (*buf & 0x80))) {
    dec->fragment_count--;
    dec->length -= len;
  } else {
    gst_adapter_push (dec->adapter,
        gst_buffer_create_sub (in, GST_BUFFER_SIZE (in) - len, len));
  }

  /* All bytes received? */
  n = gst_adapter_available (dec->adapter);
  GST_LOG_OBJECT (dec, "We know have %d bytes, and we need %d", n, dec->length);
  if (dec->length <= n) {
    guint32 tin[6] = { 0, 0, 0, 0, 0, 0 }
    , tout[5];

    if ((ret = gst_realdec_alloc_buffer (dec, timestamp, &out)) != GST_FLOW_OK)
      return ret;

    /* Decode */
    tin[0] = dec->length;
    tin[2] = dec->fragment_count - 1;
    tin[3] = (guint32) dec->fragments;
    tin[5] = GST_BUFFER_TIMESTAMP (out);
    data = gst_adapter_take (dec->adapter, dec->length);
    result = dec->transform (
        (gchar *) data,
        (gchar *) GST_BUFFER_DATA (out), tin, tout, dec->context);
    g_free (data);
    if (result)
      goto could_not_transform;

    /* Check for new dimensions */
    if (tout[0] && ((dec->width != tout[3]) || (dec->height != tout[4]))) {
      GstCaps *caps = gst_caps_copy (GST_PAD_CAPS (dec->src));
      GstStructure *s = gst_caps_get_structure (caps, 0);

      GST_DEBUG_OBJECT (dec, "New dimensions: %"
          G_GUINT32_FORMAT " x %" G_GUINT32_FORMAT, tout[3], tout[4]);
      gst_structure_set (s, "width", G_TYPE_LONG, tout[3],
          "height", G_TYPE_LONG, tout[4], NULL);
      bres = gst_pad_set_caps (dec->src, caps);
      gst_caps_unref (caps);
      if (!bres)
        goto new_dimensions_failed;
      dec->width = tout[3];
      dec->height = tout[4];
    }

    GST_DEBUG_OBJECT (dec,
        "Pushing out buffer with timestamp %" GST_TIME_FORMAT,
        GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (out)));

    if ((ret = gst_pad_push (dec->src, out)) != GST_FLOW_OK)
      goto could_not_push;

    n = gst_adapter_available (dec->adapter);
    if (n > 0) {
      GST_LOG_OBJECT (dec, "Data left in the adapter: %d", n);
      in = gst_adapter_take_buffer (dec->adapter, n);
      ret = gst_realdec_decode (dec, in, 0);
      gst_buffer_unref (in);
      if (ret != GST_FLOW_OK)
        return ret;
    }
  }

  return GST_FLOW_OK;

  /* Errors */
not_enough_data:
  {
    GST_ELEMENT_ERROR (dec, STREAM, DECODE, ("Not enough data."), (NULL));
    return GST_FLOW_ERROR;
  }

too_many_fragments:
  {
    gst_buffer_unref (in);
    GST_ELEMENT_ERROR (dec, STREAM, DECODE,
        ("Got more fragments (%i) than can be handled (%i).",
            dec->fragment_count, sizeof (dec->fragments)), (NULL));
    return GST_FLOW_ERROR;
  }

could_not_transform:
  {
    gst_buffer_unref (out);
    GST_ELEMENT_ERROR (dec, STREAM, DECODE,
        ("Could not decode buffer: %" G_GUINT32_FORMAT, result), (NULL));
    return GST_FLOW_ERROR;
  }

new_dimensions_failed:
  {
    gst_buffer_unref (out);
    GST_ELEMENT_ERROR (dec, STREAM, DECODE,
        ("Could not set new dimensions."), (NULL));
    return GST_FLOW_ERROR;
  }

could_not_push:
  {
    GST_DEBUG_OBJECT (dec, "Could not push buffer: %s",
        gst_flow_get_name (ret));
    return ret;
  }
}

static GstFlowReturn
gst_realdec_chain (GstPad * pad, GstBuffer * in)
{
  GstRealDec *dec = GST_REAL_DEC (GST_PAD_PARENT (pad));
  guint8 flags, *buf = GST_BUFFER_DATA (in);
  guint len = GST_BUFFER_SIZE (in);
  GstFlowReturn ret;

  /* Flags */
  if (len < 1)
    goto not_enough_data;
  flags = *buf;
  buf++;
  len--;

  if (flags == 0x40) {
    GST_DEBUG_OBJECT (dec, "Don't know how to handle buffer of type 0x40 "
        "(size=%i).", len);
    return GST_FLOW_OK;
  }

  ret = gst_realdec_decode (dec, in, 1);
  gst_buffer_unref (in);
  if (ret != GST_FLOW_OK)
    return ret;
  return GST_FLOW_OK;

  /* Errors */
not_enough_data:
  {
    GST_ELEMENT_ERROR (dec, STREAM, DECODE, ("Not enough data."), (NULL));
    gst_buffer_unref (in);
    return GST_FLOW_ERROR;
  }
}

static gboolean
gst_realdec_activate_push (GstPad * pad, gboolean active)
{
  GstRealDec *dec = GST_REAL_DEC (GST_PAD_PARENT (pad));

  gst_adapter_clear (dec->adapter);

  return TRUE;
}

static gboolean
gst_realdec_setcaps (GstPad * pad, GstCaps * caps)
{
  GstRealDec *dec = GST_REAL_DEC (GST_PAD_PARENT (pad));
  GstStructure *s = gst_caps_get_structure (caps, 0);
  gchar *path;
  gint version, res;
  gchar data[36];
  gboolean bres;

  if (!gst_structure_get_int (s, "rmversion", &version) ||
      !gst_structure_get_int (s, "width", (gint *) & dec->width) ||
      !gst_structure_get_int (s, "height", (gint *) & dec->height) ||
      !gst_structure_get_int (s, "format", &dec->format) ||
      !gst_structure_get_int (s, "subformat", &dec->subformat) ||
      !gst_structure_get_fraction (s, "framerate", &dec->framerate_num,
          &dec->framerate_denom))
    goto missing_keys;
  dec->version = version;

  GST_LOG_OBJECT (dec, "Setting version to %d", version);

  switch (dec->version) {
    case GST_REAL_DEC_VERSION_2:
      path = dec->path_rv20 ? dec->path_rv20 : DEFAULT_PATH_RV20;
      break;
    case GST_REAL_DEC_VERSION_3:
      path = dec->path_rv30 ? dec->path_rv30 : DEFAULT_PATH_RV30;
      break;
    case GST_REAL_DEC_VERSION_4:
      path = dec->path_rv40 ? dec->path_rv40 : DEFAULT_PATH_RV40;
      break;
    default:
      goto unknown_version;
  }

  if (dec->handle)
    dlclose (dec->handle);
  dec->handle = dlopen (path, RTLD_LAZY);
  if (!dec->handle)
    goto could_not_open;
  dec->custom_message = dlsym (dec->handle, "RV20toYUV420CustomMessage");
  dec->free = dlsym (dec->handle, "RV20toYUV420Free");
  dec->init = dlsym (dec->handle, "RV20toYUV420Init");
  dec->transform = dlsym (dec->handle, "RV20toYUV420Transform");
  if (!(dec->custom_message && dec->free && dec->init && dec->transform))
    goto could_not_load;

  /* Initialize REAL driver. */
  GST_WRITE_UINT16_LE (data + 0, 11);
  GST_WRITE_UINT16_LE (data + 2, dec->width);
  GST_WRITE_UINT16_LE (data + 4, dec->height);
  GST_WRITE_UINT16_LE (data + 6, 0);
  GST_WRITE_UINT32_LE (data + 8, 0);
  GST_WRITE_UINT32_LE (data + 12, dec->subformat);
  GST_WRITE_UINT32_LE (data + 16, 0);
  GST_WRITE_UINT32_LE (data + 20, dec->format);
  res = dec->init (&data, &dec->context);
  if (res)
    goto could_not_initialize;

  if (((dec->version == GST_REAL_DEC_VERSION_2) ||
          (dec->version == GST_REAL_DEC_VERSION_3)) &&
      (dec->format >= 0x20200002)) {
    guint32 msg[15];

    msg[0] = 0x24;
    msg[1] = 1 + ((dec->subformat >> 16) & 7);
    msg[2] = (guint32) & msg[9];
    msg[9] = dec->width;
    msg[10] = dec->height;
    msg[11] = 0xf0;
    msg[12] = 0xb0;
    msg[13] = 0xa0;
    msg[14] = 0x80;
    res = dec->custom_message (msg, dec->context);
  }

  caps = gst_caps_new_simple ("video/x-raw-yuv",
      "format", GST_TYPE_FOURCC, GST_MAKE_FOURCC ('I', '4', '2', '0'),
      "framerate", GST_TYPE_FRACTION, dec->framerate_num, dec->framerate_denom,
      "width", G_TYPE_INT, dec->width, "height", G_TYPE_INT, dec->height, NULL);
  bres = gst_pad_set_caps (GST_PAD (dec->src), caps);
  gst_caps_unref (caps);
  if (!bres)
    goto could_not_set_caps;

  return TRUE;

missing_keys:
  {
    GST_DEBUG_OBJECT (dec, "Could not find all necessary keys in structure.");
    return FALSE;
  }

unknown_version:
  {
    GST_DEBUG_OBJECT (dec, "Cannot handle version %i.", version);
    return FALSE;
  }

could_not_open:
  {
    GST_DEBUG_OBJECT (dec, "Could not open library '%s'.", path);
    return FALSE;
  }

could_not_load:
  {
    dlclose (dec->handle);
    dec->handle = NULL;
    GST_DEBUG_OBJECT (dec, "Could not load all symbols.");
    return FALSE;
  }

could_not_initialize:
  {
    dlclose (dec->handle);
    dec->handle = NULL;
    GST_DEBUG_OBJECT (dec, "Initialization of REAL driver failed (%i).");
    return FALSE;
  }

could_not_set_caps:
  {
    dlclose (dec->handle);
    dec->handle = NULL;
    GST_DEBUG_OBJECT (dec, "Could not convince peer to accept dimensions "
        "%i x %i.", dec->width, dec->height);
    return FALSE;
  }
}

static void
gst_realdec_init (GstRealDec * dec, GstRealDecClass * klass)
{
  dec->snk =
      gst_pad_new_from_template (gst_static_pad_template_get (&snk_t), "sink");
  gst_pad_set_setcaps_function (dec->snk, gst_realdec_setcaps);
  gst_pad_set_chain_function (dec->snk, gst_realdec_chain);
  gst_pad_set_activatepush_function (dec->snk, gst_realdec_activate_push);
  gst_element_add_pad (GST_ELEMENT (dec), dec->snk);

  dec->src =
      gst_pad_new_from_template (gst_static_pad_template_get (&src_t), "src");
  gst_element_add_pad (GST_ELEMENT (dec), dec->src);

  dec->adapter = g_object_new (GST_TYPE_ADAPTER, NULL);
}

static void
gst_realdec_base_init (gpointer g_class)
{
  GstElementClass *ec = GST_ELEMENT_CLASS (g_class);

  gst_element_class_add_pad_template (ec, gst_static_pad_template_get (&snk_t));
  gst_element_class_add_pad_template (ec, gst_static_pad_template_get (&src_t));
  gst_element_class_set_details (ec, &realdec_details);
}

static GstStateChangeReturn
gst_realdec_change_state (GstElement * element, GstStateChange transition)
{
  GstStateChangeReturn ret;

  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
  switch (transition) {
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      break;
    default:
      break;
  }
  return ret;
}

static void
gst_realdec_finalize (GObject * object)
{
  GstRealDec *dec = GST_REAL_DEC (object);

  if (dec->context) {
    dec->free (dec->context);
    dec->context = NULL;
  }
  if (dec->adapter) {
    g_object_unref (G_OBJECT (dec->adapter));
    dec->adapter = NULL;
  }
  if (dec->handle) {
    dlclose (dec->handle);
    dec->handle = NULL;
  }

  if (dec->path_rv20) {
    g_free (dec->path_rv20);
    dec->path_rv20 = NULL;
  }
  if (dec->path_rv30) {
    g_free (dec->path_rv30);
    dec->path_rv30 = NULL;
  }
  if (dec->path_rv40) {
    g_free (dec->path_rv40);
    dec->path_rv40 = NULL;
  }

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

static void
gst_realdec_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstRealDec *dec = GST_REAL_DEC (object);

  /* Changing the location of the .so supposes it's not being done
   * in a state greater than READY !
   */

  switch (prop_id) {
    case PROP_PATH_RV20:
      if (dec->path_rv20)
        g_free (dec->path_rv20);
      dec->path_rv20 = g_value_dup_string (value);
      break;
    case PROP_PATH_RV30:
      if (dec->path_rv30)
        g_free (dec->path_rv30);
      dec->path_rv30 = g_value_dup_string (value);
      break;
    case PROP_PATH_RV40:
      if (dec->path_rv40)
        g_free (dec->path_rv40);
      dec->path_rv40 = g_value_dup_string (value);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_realdec_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  GstRealDec *dec = GST_REAL_DEC (object);

  switch (prop_id) {
    case PROP_PATH_RV20:
      g_value_set_string (value, dec->path_rv20);
      break;
    case PROP_PATH_RV30:
      g_value_set_string (value, dec->path_rv30);
      break;
    case PROP_PATH_RV40:
      g_value_set_string (value, dec->path_rv40);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_realdec_class_init (GstRealDecClass * klass)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
  GObjectClass *object_class = G_OBJECT_CLASS (klass);

  object_class->set_property = gst_realdec_set_property;
  object_class->get_property = gst_realdec_get_property;
  object_class->finalize = gst_realdec_finalize;

  element_class->change_state = gst_realdec_change_state;

  g_object_class_install_property (object_class, PROP_PATH_RV20,
      g_param_spec_string ("path_rv20", "Path to rv20 driver",
          "Path to rv20 driver", DEFAULT_PATH_RV20, G_PARAM_READWRITE));
  g_object_class_install_property (object_class, PROP_PATH_RV30,
      g_param_spec_string ("path_rv30", "Path to rv30 driver",
          "Path to rv30 driver", DEFAULT_PATH_RV30, G_PARAM_READWRITE));
  g_object_class_install_property (object_class, PROP_PATH_RV40,
      g_param_spec_string ("path_rv40", "Path to rv40 driver",
          "Path to rv40 driver", DEFAULT_PATH_RV40, G_PARAM_READWRITE));

  GST_DEBUG_CATEGORY_INIT (realdec_debug, "realdec", 0, "REAL decoder");
}

static gboolean
plugin_init (GstPlugin * p)
{
  if (!gst_element_register (p, "realdec", GST_RANK_PRIMARY, GST_TYPE_REAL_DEC))
    return FALSE;
  return TRUE;
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR, GST_VERSION_MINOR, "real",
    "Decode REAL streams",
    plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)