gst_plugins_base/ext/ogg/gstoggparse.c
branchRCL_3
changeset 30 7e817e7e631c
parent 0 0e761a78d257
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gst_plugins_base/ext/ogg/gstoggparse.c	Wed Sep 01 12:16:41 2010 +0100
@@ -0,0 +1,695 @@
+/* GStreamer
+ * Copyright (C) 2005 Michael Smith <msmith@fluendo.com>
+ *
+ * gstoggparse.c: ogg stream parser
+ *
+ * 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.
+ */
+
+/* This ogg parser is essentially a subset of the ogg demuxer - rather than
+ * fully demuxing into packets, we only parse out the pages, create one
+ * GstBuffer per page, set all the appropriate flags on those pages, set caps
+ * appropriately (particularly the 'streamheader' which gives all the header
+ * pages required for initialing decode).
+ *
+ * It's dramatically simpler than the full demuxer as it does not  support 
+ * seeking.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#include <gst/gst.h>
+#include <ogg/ogg.h>
+#include <string.h>
+
+static const GstElementDetails gst_ogg_parse_details =
+GST_ELEMENT_DETAILS ("Ogg parser",
+    "Codec/Parser",
+    "parse ogg streams into pages (info about ogg: http://xiph.org)",
+    "Michael Smith <msmith@fluendo.com>");
+
+GST_DEBUG_CATEGORY_STATIC (gst_ogg_parse_debug);
+#define GST_CAT_DEFAULT gst_ogg_parse_debug
+
+#define GST_TYPE_OGG_PARSE (gst_ogg_parse_get_type())
+#define GST_OGG_PARSE(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_OGG_PARSE, GstOggParse))
+#define GST_OGG_PARSE_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_OGG_PARSE, GstOggParse))
+#define GST_IS_OGG_PARSE(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_OGG_PARSE))
+#define GST_IS_OGG_PARSE_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_OGG_PARSE))
+
+static GType gst_ogg_parse_get_type (void);
+
+typedef struct _GstOggParse GstOggParse;
+typedef struct _GstOggParseClass GstOggParseClass;
+
+/* Each ogg logical stream has a GstOggStream associated with it */
+typedef struct
+{
+  /*ogg_stream_state stream; *//* We need this to get the packets out in order
+     to do codec identification, for various
+     codec-specific tasks */
+
+  gboolean in_headers;          /* Initially true, false once we've read all the
+                                   headers for this logical stream */
+
+  guint32 serialno;             /* Unique serial number of this stream */
+
+  GSList *headers;              /* List of ogg pages that we'll set on caps */
+  GSList *unknown_pages;        /* List of pages we haven't yet classified */
+} GstOggStream;
+
+struct _GstOggParse
+{
+  GstElement element;
+
+  GstPad *sinkpad;              /* Sink pad we're reading data from */
+
+  GstPad *srcpad;               /* Source pad we're writing to */
+
+  GSList *oggstreams;           /* list of GstOggStreams for known streams */
+
+  gint64 offset;                /* Current stream offset */
+
+  gboolean in_headers;          /* Set if we're reading headers for streams */
+
+  gboolean last_page_not_bos;   /* Set if we've seen a non-BOS page */
+
+  ogg_sync_state sync;          /* Ogg page synchronisation */
+
+  GstCaps *caps;                /* Our src caps */
+};
+
+struct _GstOggParseClass
+{
+  GstElementClass parent_class;
+};
+
+static void gst_ogg_parse_base_init (gpointer g_class);
+static void gst_ogg_parse_class_init (GstOggParseClass * klass);
+static void gst_ogg_parse_init (GstOggParse * ogg);
+static GstElementClass *parent_class = NULL;
+
+static GType
+gst_ogg_parse_get_type (void)
+{
+  static GType ogg_parse_type = 0;
+
+  if (!ogg_parse_type) {
+    static const GTypeInfo ogg_parse_info = {
+      sizeof (GstOggParseClass),
+      gst_ogg_parse_base_init,
+      NULL,
+      (GClassInitFunc) gst_ogg_parse_class_init,
+      NULL,
+      NULL,
+      sizeof (GstOggParse),
+      0,
+      (GInstanceInitFunc) gst_ogg_parse_init,
+    };
+
+    ogg_parse_type = g_type_register_static (GST_TYPE_ELEMENT, "GstOggParse",
+        &ogg_parse_info, 0);
+  }
+  return ogg_parse_type;
+}
+
+static void
+free_stream (GstOggStream * stream)
+{
+  g_slist_foreach (stream->headers, (GFunc) gst_mini_object_unref, NULL);
+  g_slist_foreach (stream->unknown_pages, (GFunc) gst_mini_object_unref, NULL);
+
+  g_free (stream);
+}
+
+static void
+gst_ogg_parse_delete_all_streams (GstOggParse * ogg)
+{
+  g_slist_foreach (ogg->oggstreams, (GFunc) free_stream, NULL);
+  g_slist_free (ogg->oggstreams);
+  ogg->oggstreams = NULL;
+}
+
+static GstOggStream *
+gst_ogg_parse_new_stream (GstOggParse * parser, guint32 serialno)
+{
+  GstOggStream *ret;
+
+  GST_DEBUG_OBJECT (parser, "creating new stream %08x", serialno);
+
+  ret = g_new0 (GstOggStream, 1);
+
+  ret->serialno = serialno;
+  ret->in_headers = 1;
+
+  /*
+     if (ogg_stream_init (&ret->stream, serialno) != 0) {
+     GST_ERROR ("Could not initialize ogg_stream struct for serial %08lx.",
+     serialno);
+     return NULL;
+     }
+   */
+
+  parser->oggstreams = g_slist_append (parser->oggstreams, ret);
+
+  return ret;
+}
+
+static GstOggStream *
+gst_ogg_parse_find_stream (GstOggParse * parser, guint32 serialno)
+{
+  GSList *l;
+
+  for (l = parser->oggstreams; l != NULL; l = l->next) {
+    GstOggStream *stream = (GstOggStream *) l->data;
+
+    if (stream->serialno == serialno)
+      return stream;
+  }
+  return NULL;
+}
+
+/* signals and args */
+enum
+{
+  /* FILL ME */
+  LAST_SIGNAL
+};
+
+enum
+{
+  ARG_0
+      /* FILL ME */
+};
+
+static GstStaticPadTemplate ogg_parse_src_template_factory =
+GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("application/ogg")
+    );
+
+static GstStaticPadTemplate ogg_parse_sink_template_factory =
+GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("application/ogg")
+    );
+
+static void gst_ogg_parse_dispose (GObject * object);
+static GstStateChangeReturn gst_ogg_parse_change_state (GstElement * element,
+    GstStateChange transition);
+static GstFlowReturn gst_ogg_parse_chain (GstPad * pad, GstBuffer * buffer);
+
+static void
+gst_ogg_parse_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_set_details (element_class, &gst_ogg_parse_details);
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&ogg_parse_sink_template_factory));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&ogg_parse_src_template_factory));
+}
+
+static void
+gst_ogg_parse_class_init (GstOggParseClass * klass)
+{
+  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  parent_class = g_type_class_peek_parent (klass);
+
+  gstelement_class->change_state = gst_ogg_parse_change_state;
+
+  gobject_class->dispose = gst_ogg_parse_dispose;
+}
+
+static void
+gst_ogg_parse_init (GstOggParse * ogg)
+{
+  /* create the sink and source pads */
+  ogg->sinkpad =
+      gst_pad_new_from_static_template (&ogg_parse_sink_template_factory,
+      "sink");
+  ogg->srcpad =
+      gst_pad_new_from_static_template (&ogg_parse_src_template_factory, "src");
+
+  /* TODO: Are there any events we must handle? */
+  /* gst_pad_set_event_function (ogg->sinkpad, gst_ogg_parse_handle_event); */
+  gst_pad_set_chain_function (ogg->sinkpad, gst_ogg_parse_chain);
+
+  gst_element_add_pad (GST_ELEMENT (ogg), ogg->sinkpad);
+  gst_element_add_pad (GST_ELEMENT (ogg), ogg->srcpad);
+
+  ogg->oggstreams = NULL;
+}
+
+static void
+gst_ogg_parse_dispose (GObject * object)
+{
+  GstOggParse *ogg = GST_OGG_PARSE (object);
+
+  GST_LOG_OBJECT (ogg, "Disposing of object %p", ogg);
+
+  ogg_sync_clear (&ogg->sync);
+  gst_ogg_parse_delete_all_streams (ogg);
+
+  if (ogg->caps) {
+    gst_caps_unref (ogg->caps);
+    ogg->caps = NULL;
+  }
+
+  if (G_OBJECT_CLASS (parent_class)->dispose)
+    G_OBJECT_CLASS (parent_class)->dispose (object);
+}
+
+/* submit the given buffer to the ogg sync.
+ *
+ * Returns the number of bytes submited.
+ */
+static gint
+gst_ogg_parse_submit_buffer (GstOggParse * ogg, GstBuffer * buffer)
+{
+  guint size;
+  guint8 *data;
+  gchar *oggbuffer;
+
+  size = GST_BUFFER_SIZE (buffer);
+  data = GST_BUFFER_DATA (buffer);
+
+  /* We now have a buffer, submit it to the ogg sync layer */
+  oggbuffer = ogg_sync_buffer (&ogg->sync, size);
+  memcpy (oggbuffer, data, size);
+  ogg_sync_wrote (&ogg->sync, size);
+
+  /* We've copied all the neccesary data, so we're done with the buffer */
+  gst_buffer_unref (buffer);
+
+  return size;
+}
+
+static void
+gst_ogg_parse_append_header (GValue * array, GstBuffer * buf)
+{
+  GValue value = { 0 };
+  /* We require a copy to avoid circular refcounts */
+  GstBuffer *buffer = gst_buffer_copy (buf);
+
+  GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_IN_CAPS);
+
+  g_value_init (&value, GST_TYPE_BUFFER);
+  gst_value_set_buffer (&value, buffer);
+  gst_value_array_append_value (array, &value);
+  g_value_unset (&value);
+
+}
+
+typedef enum
+{
+  PAGE_HEADER,                  /* Header page */
+  PAGE_DATA,                    /* Data page */
+  PAGE_PENDING,                 /* We don't know yet, we'll have to see some future pages */
+} page_type;
+
+static page_type
+gst_ogg_parse_is_header (GstOggParse * ogg, GstOggStream * stream,
+    ogg_page * page)
+{
+  ogg_int64_t gpos = ogg_page_granulepos (page);
+
+  if (gpos < 0)
+    return PAGE_PENDING;
+
+  /* This is good enough for now, but technically requires codec-specific
+   * behaviour to be perfect. This is where we need the mooted library for 
+   * this stuff, which nobody has written.
+   */
+  if (gpos > 0)
+    return PAGE_DATA;
+  else
+    return PAGE_HEADER;
+}
+
+static GstBuffer *
+gst_ogg_parse_buffer_from_page (ogg_page * page,
+    guint64 offset, gboolean delta, GstClockTime timestamp)
+{
+  int size = page->header_len + page->body_len;
+  GstBuffer *buf = gst_buffer_new_and_alloc (size);
+
+  memcpy (GST_BUFFER_DATA (buf), page->header, page->header_len);
+  memcpy (GST_BUFFER_DATA (buf) + page->header_len, page->body, page->body_len);
+
+  GST_BUFFER_TIMESTAMP (buf) = timestamp;
+  GST_BUFFER_OFFSET (buf) = offset;
+  GST_BUFFER_OFFSET_END (buf) = offset + size;
+
+  return buf;
+}
+
+
+/* Reads in buffers, parses them, reframes into one-buffer-per-ogg-page, submits
+ * pages to output pad.
+ */
+static GstFlowReturn
+gst_ogg_parse_chain (GstPad * pad, GstBuffer * buffer)
+{
+  GstOggParse *ogg;
+  GstFlowReturn result = GST_FLOW_OK;
+  gint ret = -1;
+  guint32 serialno;
+  GstBuffer *pagebuffer;
+  GstClockTime buffertimestamp = GST_BUFFER_TIMESTAMP (buffer);
+
+  ogg = GST_OGG_PARSE (GST_OBJECT_PARENT (pad));
+
+  GST_LOG_OBJECT (ogg, "Chain function received buffer of size %d",
+      GST_BUFFER_SIZE (buffer));
+
+  gst_ogg_parse_submit_buffer (ogg, buffer);
+
+  while (ret != 0 && result == GST_FLOW_OK) {
+    ogg_page page;
+
+    /* We use ogg_sync_pageseek() rather than ogg_sync_pageout() so that we can
+     * track how many bytes the ogg layer discarded (in the case of sync errors,
+     * etc.); this allows us to accurately track the current stream offset
+     */
+    ret = ogg_sync_pageseek (&ogg->sync, &page);
+    if (ret == 0) {
+      /* need more data, that's fine... */
+      break;
+    } else if (ret < 0) {
+      /* discontinuity; track how many bytes we skipped (-ret) */
+      ogg->offset -= ret;
+    } else {
+#ifndef GST_DISABLE_GST_DEBUG
+      gint64 granule = ogg_page_granulepos (&page);
+      int bos = ogg_page_bos (&page);
+#endif
+      guint64 startoffset = ogg->offset;
+
+      GST_LOG_OBJECT (ogg, "Timestamping outgoing buffer as %" GST_TIME_FORMAT,
+          GST_TIME_ARGS (buffertimestamp));
+      /* Turn our page into a GstBuffer TODO: better timestamps? Requires format
+       * parsing. */
+      pagebuffer = gst_ogg_parse_buffer_from_page (&page, startoffset, FALSE,
+          buffertimestamp);
+
+      /* We read out 'ret' bytes, so we set the next offset appropriately */
+      ogg->offset += ret;
+
+      serialno = ogg_page_serialno (&page);
+
+      GST_LOG_OBJECT (ogg,
+          "processing ogg page (serial %08x, pageno %ld, "
+          "granule pos %" G_GUINT64_FORMAT ", bos %d, offset %"
+          G_GUINT64_FORMAT "-%" G_GUINT64_FORMAT ")",
+          serialno, ogg_page_pageno (&page),
+          granule, bos, startoffset, ogg->offset);
+
+      if (ogg_page_bos (&page)) {
+        /* If we've seen this serialno before, this is technically an error,
+         * we log this case but accept it - this one replaces the previous
+         * stream with this serialno. We can do this since we're streaming, and
+         * not supporting seeking...
+         */
+        GstOggStream *stream = gst_ogg_parse_find_stream (ogg, serialno);
+
+        if (stream != NULL) {
+          GST_LOG_OBJECT (ogg, "Incorrect stream; repeats serial number %u "
+              "at offset %lld", serialno, ogg->offset);
+        }
+
+        if (ogg->last_page_not_bos) {
+          GST_LOG_OBJECT (ogg, "Deleting all referenced streams, found a new "
+              "chain starting with serial %u", serialno);
+          gst_ogg_parse_delete_all_streams (ogg);
+        }
+
+        stream = gst_ogg_parse_new_stream (ogg, serialno);
+
+        ogg->last_page_not_bos = FALSE;
+
+        gst_buffer_ref (pagebuffer);
+        stream->headers = g_slist_append (stream->headers, pagebuffer);
+
+        if (!ogg->in_headers) {
+          GST_LOG_OBJECT (ogg, "Found start of new chain at offset %llu",
+              startoffset);
+          ogg->in_headers = 1;
+        }
+
+        /* For now, we just keep the header buffer in the stream->headers list;
+         * it actually gets output once we've collected the entire set
+         */
+      } else {
+        /* Non-BOS page. Either: we're outside headers, and this isn't a 
+         * header (normal data), outside headers and this is (error!), inside
+         * headers, this is (append header), or inside headers and this isn't 
+         * (we've found the end of headers; flush the lot!)
+         *
+         * Before that, we flag that the last page seen (this one) was not a 
+         * BOS page; that way we know that when we next see a BOS page it's a
+         * new chain, and we can flush all existing streams.
+         */
+        page_type type;
+        GstOggStream *stream = gst_ogg_parse_find_stream (ogg, serialno);
+
+        if (!stream) {
+          GST_LOG_OBJECT (ogg, "Non-BOS page unexpectedly found at %lld",
+              ogg->offset);
+          goto failure;
+        }
+
+        ogg->last_page_not_bos = TRUE;
+
+        type = gst_ogg_parse_is_header (ogg, stream, &page);
+
+        if (type == PAGE_PENDING && ogg->in_headers) {
+          gst_buffer_ref (pagebuffer);
+
+          stream->unknown_pages = g_slist_append (stream->unknown_pages,
+              pagebuffer);
+        } else if (type == PAGE_HEADER) {
+          if (!ogg->in_headers) {
+            GST_LOG_OBJECT (ogg, "Header page unexpectedly found outside "
+                "headers at offset %lld", ogg->offset);
+            goto failure;
+          } else {
+            /* Append the header to the buffer list, after any unknown previous
+             * pages
+             */
+            stream->headers = g_slist_concat (stream->headers,
+                stream->unknown_pages);
+            g_slist_free (stream->unknown_pages);
+            gst_buffer_ref (pagebuffer);
+            stream->headers = g_slist_append (stream->headers, pagebuffer);
+          }
+        } else {                /* PAGE_DATA, or PAGE_PENDING but outside headers */
+          if (ogg->in_headers) {
+            /* First non-header page... set caps, flush headers.
+             *
+             * First up, we build a single GValue list of all the pagebuffers
+             * we're using for the headers, in order.
+             * Then we set this on the caps structure. Then we can start pushing
+             * buffers for the headers, and finally we send this non-header
+             * page.
+             */
+            GstCaps *caps;
+            GstStructure *structure;
+            GValue array = { 0 };
+            gint count = 0;
+            gboolean found_pending_headers = FALSE;
+            GSList *l;
+
+            g_value_init (&array, GST_TYPE_ARRAY);
+
+            for (l = ogg->oggstreams; l != NULL; l = l->next) {
+              GstOggStream *stream = (GstOggStream *) l->data;
+
+              if (g_slist_length (stream->headers) == 0) {
+                GST_LOG_OBJECT (ogg, "No primary header found for stream %u",
+                    stream->serialno);
+                goto failure;
+              }
+
+              gst_ogg_parse_append_header (&array,
+                  GST_BUFFER (stream->headers->data));
+              count++;
+            }
+
+            for (l = ogg->oggstreams; l != NULL; l = l->next) {
+              GstOggStream *stream = (GstOggStream *) l->data;
+              int j;
+
+              for (j = 1; j < g_slist_length (stream->headers); j++) {
+                gst_ogg_parse_append_header (&array,
+                    GST_BUFFER (g_slist_nth_data (stream->headers, j)));
+                count++;
+              }
+            }
+
+            caps = gst_pad_get_caps (ogg->srcpad);
+            caps = gst_caps_make_writable (caps);
+
+            structure = gst_caps_get_structure (caps, 0);
+            gst_structure_set_value (structure, "streamheader", &array);
+
+            gst_pad_set_caps (ogg->srcpad, caps);
+
+            g_value_unset (&array);
+
+            if (ogg->caps)
+              gst_caps_unref (ogg->caps);
+            ogg->caps = caps;
+
+            GST_LOG_OBJECT (ogg, "Set \"streamheader\" caps with %d buffers "
+                "(one per page)", count);
+
+            /* Now, we do the same thing, but push buffers... */
+            for (l = ogg->oggstreams; l != NULL; l = l->next) {
+              GstOggStream *stream = (GstOggStream *) l->data;
+              GstBuffer *buf = GST_BUFFER (stream->headers->data);
+
+              gst_buffer_set_caps (buf, caps);
+
+              result = gst_pad_push (ogg->srcpad, buf);
+              if (result != GST_FLOW_OK)
+                return result;
+            }
+            for (l = ogg->oggstreams; l != NULL; l = l->next) {
+              GstOggStream *stream = (GstOggStream *) l->data;
+              int j;
+
+              for (j = 1; j < g_slist_length (stream->headers); j++) {
+                GstBuffer *buf =
+                    GST_BUFFER (g_slist_nth_data (stream->headers, j));
+                gst_buffer_set_caps (buf, caps);
+
+                result = gst_pad_push (ogg->srcpad, buf);
+                if (result != GST_FLOW_OK)
+                  return result;
+              }
+            }
+
+            ogg->in_headers = 0;
+
+            /* And finally the pending data pages */
+            for (l = ogg->oggstreams; l != NULL; l = l->next) {
+              GstOggStream *stream = (GstOggStream *) l->data;
+              GSList *k;
+
+              if (stream->unknown_pages == NULL)
+                continue;
+
+              if (found_pending_headers) {
+                GST_WARNING_OBJECT (ogg, "Incorrectly muxed headers found at "
+                    "approximate offset %lld", ogg->offset);
+              }
+              found_pending_headers = TRUE;
+
+              GST_LOG_OBJECT (ogg, "Pushing %d pending pages after headers",
+                  g_slist_length (stream->unknown_pages) + 1);
+
+              for (k = stream->unknown_pages; k != NULL; k = k->next) {
+                GstBuffer *buf;
+
+                buf = GST_BUFFER (k->data);
+                gst_buffer_set_caps (buf, caps);
+                result = gst_pad_push (ogg->srcpad, buf);
+                if (result != GST_FLOW_OK)
+                  return result;
+              }
+              g_slist_foreach (stream->unknown_pages,
+                  (GFunc) gst_mini_object_unref, NULL);
+              g_slist_free (stream->unknown_pages);
+              stream->unknown_pages = NULL;
+            }
+
+            gst_buffer_set_caps (pagebuffer, caps);
+
+            result = gst_pad_push (ogg->srcpad, GST_BUFFER (pagebuffer));
+            if (result != GST_FLOW_OK)
+              return result;
+          } else {
+            /* Normal data page, submit buffer */
+            gst_buffer_set_caps (pagebuffer, ogg->caps);
+            result = gst_pad_push (ogg->srcpad, GST_BUFFER (pagebuffer));
+            if (result != GST_FLOW_OK)
+              return result;
+          }
+        }
+      }
+    }
+  }
+
+  return result;
+
+failure:
+  gst_pad_push_event (GST_PAD (ogg->srcpad), gst_event_new_eos ());
+  return GST_FLOW_ERROR;
+}
+
+static GstStateChangeReturn
+gst_ogg_parse_change_state (GstElement * element, GstStateChange transition)
+{
+  GstOggParse *ogg;
+  GstStateChangeReturn result = GST_STATE_CHANGE_FAILURE;
+
+  ogg = GST_OGG_PARSE (element);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_NULL_TO_READY:
+      ogg_sync_init (&ogg->sync);
+      break;
+    case GST_STATE_CHANGE_READY_TO_PAUSED:
+      ogg_sync_reset (&ogg->sync);
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
+      break;
+    default:
+      break;
+  }
+
+  result = parent_class->change_state (element, transition);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_READY:
+      break;
+    case GST_STATE_CHANGE_READY_TO_NULL:
+      ogg_sync_clear (&ogg->sync);
+      break;
+    default:
+      break;
+  }
+  return result;
+}
+
+gboolean
+gst_ogg_parse_plugin_init (GstPlugin * plugin)
+{
+  GST_DEBUG_CATEGORY_INIT (gst_ogg_parse_debug, "oggparse", 0, "ogg parser");
+
+  return gst_element_register (plugin, "oggparse", GST_RANK_NONE,
+      GST_TYPE_OGG_PARSE);
+}