--- a/gst_plugins_base/gst-libs/gst/rtp/gstrtpbuffer.c	Tue Aug 31 15:30:33 2010 +0300
+++ b/gst_plugins_base/gst-libs/gst/rtp/gstrtpbuffer.c	Wed Sep 01 12:16:41 2010 +0100
@@ -69,19 +69,20 @@
   guint8 csrclist[4];           /* optional CSRC list, 32 bits each */
 } GstRTPHeader;
 
-#define GST_RTP_HEADER_VERSION(data)      (((GstRTPHeader *)(data))->version)
-#define GST_RTP_HEADER_PADDING(data)      (((GstRTPHeader *)(data))->padding)
-#define GST_RTP_HEADER_EXTENSION(data)    (((GstRTPHeader *)(data))->extension)
-#define GST_RTP_HEADER_CSRC_COUNT(data)   (((GstRTPHeader *)(data))->csrc_count)
-#define GST_RTP_HEADER_MARKER(data)       (((GstRTPHeader *)(data))->marker)
-#define GST_RTP_HEADER_PAYLOAD_TYPE(data) (((GstRTPHeader *)(data))->payload_type)
-#define GST_RTP_HEADER_SEQ(data)          (((GstRTPHeader *)(data))->seq)
-#define GST_RTP_HEADER_TIMESTAMP(data)    (((GstRTPHeader *)(data))->timestamp)
-#define GST_RTP_HEADER_SSRC(data)         (((GstRTPHeader *)(data))->ssrc)
-#define GST_RTP_HEADER_CSRC_LIST_OFFSET(data,i)        \
-    data + G_STRUCT_OFFSET(GstRTPHeader, csrclist) +   \
+#define GST_RTP_HEADER_VERSION(buf)     (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->version)
+#define GST_RTP_HEADER_PADDING(buf)     (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->padding)
+#define GST_RTP_HEADER_EXTENSION(buf)   (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->extension)
+#define GST_RTP_HEADER_CSRC_COUNT(buf)  (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->csrc_count)
+#define GST_RTP_HEADER_MARKER(buf)      (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->marker)
+#define GST_RTP_HEADER_PAYLOAD_TYPE(buf)(((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->payload_type)
+#define GST_RTP_HEADER_SEQ(buf)         (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->seq)
+#define GST_RTP_HEADER_TIMESTAMP(buf)   (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->timestamp)
+#define GST_RTP_HEADER_SSRC(buf)        (((GstRTPHeader *)(GST_BUFFER_DATA (buf)))->ssrc)
+#define GST_RTP_HEADER_CSRC_LIST_OFFSET(buf,i)  \
+    GST_BUFFER_DATA (buf) +                     \
+    G_STRUCT_OFFSET(GstRTPHeader, csrclist) +   \
     ((i) * sizeof(guint32))
-#define GST_RTP_HEADER_CSRC_SIZE(data)   (GST_RTP_HEADER_CSRC_COUNT(data) * sizeof (guint32))
+#define GST_RTP_HEADER_CSRC_SIZE(buf)   (GST_RTP_HEADER_CSRC_COUNT(buf) * sizeof (guint32))
 
 /**
  * gst_rtp_buffer_allocate_data:
@@ -104,7 +105,6 @@
     guint8 pad_len, guint8 csrc_count)
 {
   guint len;
-  guint8 *data;
 
   g_return_if_fail (csrc_count <= 15);
   g_return_if_fail (GST_IS_BUFFER (buffer));
@@ -112,23 +112,22 @@
   len = GST_RTP_HEADER_LEN + csrc_count * sizeof (guint32)
       + payload_len + pad_len;
 
-  data = g_malloc (len);
-  GST_BUFFER_MALLOCDATA (buffer) = data;
-  GST_BUFFER_DATA (buffer) = data;
+  GST_BUFFER_MALLOCDATA (buffer) = g_malloc (len);
+  GST_BUFFER_DATA (buffer) = GST_BUFFER_MALLOCDATA (buffer);
   GST_BUFFER_SIZE (buffer) = len;
 
   /* fill in defaults */
-  GST_RTP_HEADER_VERSION (data) = GST_RTP_VERSION;
-  GST_RTP_HEADER_PADDING (data) = FALSE;
-  GST_RTP_HEADER_EXTENSION (data) = FALSE;
-  GST_RTP_HEADER_CSRC_COUNT (data) = csrc_count;
-  memset (GST_RTP_HEADER_CSRC_LIST_OFFSET (data, 0), 0,
+  GST_RTP_HEADER_VERSION (buffer) = GST_RTP_VERSION;
+  GST_RTP_HEADER_PADDING (buffer) = FALSE;
+  GST_RTP_HEADER_EXTENSION (buffer) = FALSE;
+  GST_RTP_HEADER_CSRC_COUNT (buffer) = csrc_count;
+  memset (GST_RTP_HEADER_CSRC_LIST_OFFSET (buffer, 0), 0,
       csrc_count * sizeof (guint32));
-  GST_RTP_HEADER_MARKER (data) = FALSE;
-  GST_RTP_HEADER_PAYLOAD_TYPE (data) = 0;
-  GST_RTP_HEADER_SEQ (data) = 0;
-  GST_RTP_HEADER_TIMESTAMP (data) = 0;
-  GST_RTP_HEADER_SSRC (data) = 0;
+  GST_RTP_HEADER_MARKER (buffer) = FALSE;
+  GST_RTP_HEADER_PAYLOAD_TYPE (buffer) = 0;
+  GST_RTP_HEADER_SEQ (buffer) = 0;
+  GST_RTP_HEADER_TIMESTAMP (buffer) = 0;
+  GST_RTP_HEADER_SSRC (buffer) = 0;
 }
 
 /**
@@ -317,18 +316,23 @@
 }
 
 /**
- * validate_data:
+ * gst_rtp_buffer_validate_data:
  * @data: the data to validate
  * @len: the length of @data to validate
- * @payload: the payload if @data represents the header only
- * @payload_len: the len of the payload
  *
- * Checks if @data is a valid RTP packet.
+ * Check if the @data and @size point to the data of a valid RTP packet.
+ * This function checks the length, version and padding of the packet data.
+ * Use this function to validate a packet before using the other functions in
+ * this module.
  *
- * Returns: TRUE if @data is a valid RTP packet
+ * Returns: TRUE if the data points to a valid RTP packet.
  */
-static gboolean
-validate_data (guint8 * data, guint len, guint8 * payload, guint payload_len)
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_rtp_buffer_validate_data (guint8 * data, guint len)
 {
   guint8 padding;
   guint8 csrc_count;
@@ -342,8 +346,8 @@
     goto wrong_length;
 
   /* check version */
-  version = (data[0] & 0xc0);
-  if (G_UNLIKELY (version != (GST_RTP_VERSION << 6)))
+  version = (data[0] & 0xc0) >> 6;
+  if (G_UNLIKELY (version != GST_RTP_VERSION))
     goto wrong_version;
 
   /* calc header length with csrc */
@@ -372,17 +376,13 @@
   }
 
   /* check for padding */
-  if (data[0] & 0x20) {
-    if (payload)
-      padding = payload[payload_len - 1];
-    else
-      padding = data[len - 1];
-  } else {
+  if (data[0] & 0x20)
+    padding = data[len - 1];
+  else
     padding = 0;
-  }
 
-  /* check if padding and header not bigger than packet length */
-  if (G_UNLIKELY (len < padding + header_len))
+  /* check if padding not bigger than packet and header */
+  if (G_UNLIKELY (len - header_len < padding))
     goto wrong_padding;
 
   return TRUE;
@@ -406,35 +406,11 @@
 }
 
 /**
- * gst_rtp_buffer_validate_data:
- * @data: the data to validate
- * @len: the length of @data to validate
- *
- * Check if the @data and @size point to the data of a valid RTP packet.
- * This function checks the length, version and padding of the packet data.
- * Use this function to validate a packet before using the other functions in
- * this module.
- *
- * Returns: TRUE if the data points to a valid RTP packet.
- */
-#ifdef __SYMBIAN32__
-EXPORT_C
-#endif
-
-gboolean
-gst_rtp_buffer_validate_data (guint8 * data, guint len)
-{
-  return validate_data (data, len, NULL, 0);
-}
-
-/**
  * gst_rtp_buffer_validate:
  * @buffer: the buffer to validate
  *
  * Check if the data pointed to by @buffer is a valid RTP packet using
- * validate_data().
- * Use this function to validate a packet before using the other functions in
- * this module.
+ * gst_rtp_buffer_validate_data().
  *
  * Returns: TRUE if @buffer is a valid RTP packet.
  */
@@ -453,99 +429,7 @@
   data = GST_BUFFER_DATA (buffer);
   len = GST_BUFFER_SIZE (buffer);
 
-  return validate_data (data, len, NULL, 0);
-}
-
-/**
- * gst_rtp_buffer_list_validate:
- * @list: the buffer list to validate
- *
- * Check if all RTP packets in the @list are valid using validate_data().
- * Use this function to validate an list before using the other functions in
- * this module.
- *
- * Returns: TRUE if @list consists only of valid RTP packets.
- *
- * Since: 0.10.24
- */
- 
- #ifdef __SYMBIAN32__
-EXPORT_C
-#endif
-
-gboolean
-gst_rtp_buffer_list_validate (GstBufferList * list)
-{
-  guint16 prev_seqnum = 0;
-  GstBufferListIterator *it;
-  guint i = 0;
-
-  g_return_val_if_fail (GST_IS_BUFFER_LIST (list), FALSE);
-
-  it = gst_buffer_list_iterate (list);
-  g_return_val_if_fail (it != NULL, FALSE);
-
-  /* iterate through all the RTP packets in the list */
-  while (gst_buffer_list_iterator_next_group (it)) {
-    GstBuffer *rtpbuf;
-    GstBuffer *paybuf;
-    guint8 *packet_header;
-    guint8 *packet_payload;
-    guint payload_size;
-    guint packet_size;
-
-    /* each group should consists of 2 buffers: one containing the RTP header
-     * and the other one the payload, FIXME, relax the requirement of only one
-     * payload buffer. */
-    if (gst_buffer_list_iterator_n_buffers (it) != 2)
-      goto invalid_list;
-
-    /* get the RTP header */
-    rtpbuf = gst_buffer_list_iterator_next (it);
-    packet_header = GST_BUFFER_DATA (rtpbuf);
-    if (packet_header == NULL)
-      goto invalid_list;
-
-    /* get the payload */
-    paybuf = gst_buffer_list_iterator_next (it);
-    packet_payload = GST_BUFFER_DATA (paybuf);
-    if (packet_payload == NULL) {
-      goto invalid_list;
-    }
-    payload_size = GST_BUFFER_SIZE (paybuf);
-    if (payload_size == 0) {
-      goto invalid_list;
-    }
-
-    /* the size of the RTP packet within the current group */
-    packet_size = GST_BUFFER_SIZE (rtpbuf) + payload_size;
-
-    /* check the sequence number */
-    if (G_UNLIKELY (i == 0)) {
-      prev_seqnum = g_ntohs (GST_RTP_HEADER_SEQ (packet_header));
-      i++;
-    } else {
-      if (++prev_seqnum != g_ntohs (GST_RTP_HEADER_SEQ (packet_header)))
-        goto invalid_list;
-    }
-
-    /* validate packet */
-    if (!validate_data (packet_header, packet_size, packet_payload,
-            payload_size)) {
-      goto invalid_list;
-    }
-  }
-
-  gst_buffer_list_iterator_free (it);
-
-  return TRUE;
-
-  /* ERRORS */
-invalid_list:
-  {
-    gst_buffer_list_iterator_free (it);
-    return FALSE;
-  }
+  return gst_rtp_buffer_validate_data (data, len);
 }
 
 /**
@@ -564,20 +448,22 @@
 gst_rtp_buffer_set_packet_len (GstBuffer * buffer, guint len)
 {
   guint oldlen;
-  guint8 *data;
+
+  g_return_if_fail (GST_IS_BUFFER (buffer));
 
   oldlen = GST_BUFFER_SIZE (buffer);
-  data = GST_BUFFER_DATA (buffer);
 
   if (oldlen < len) {
-    data = g_realloc (GST_BUFFER_MALLOCDATA (buffer), len);
-    GST_BUFFER_MALLOCDATA (buffer) = data;
-    GST_BUFFER_DATA (buffer) = data;
+    guint8 *newdata;
+
+    newdata = g_realloc (GST_BUFFER_MALLOCDATA (buffer), len);
+    GST_BUFFER_MALLOCDATA (buffer) = newdata;
+    GST_BUFFER_DATA (buffer) = newdata;
   }
   GST_BUFFER_SIZE (buffer) = len;
 
   /* remove any padding */
-  GST_RTP_HEADER_PADDING (data) = FALSE;
+  GST_RTP_HEADER_PADDING (buffer) = FALSE;
 }
 
 /**
@@ -595,6 +481,8 @@
 guint
 gst_rtp_buffer_get_packet_len (GstBuffer * buffer)
 {
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+
   return GST_BUFFER_SIZE (buffer);
 }
 
@@ -615,13 +503,12 @@
 gst_rtp_buffer_get_header_len (GstBuffer * buffer)
 {
   guint len;
-  guint8 *data;
 
-  data = GST_BUFFER_DATA (buffer);
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
 
-  len = GST_RTP_HEADER_LEN + GST_RTP_HEADER_CSRC_SIZE (data);
-  if (GST_RTP_HEADER_EXTENSION (data))
-    len += GST_READ_UINT16_BE (data + len + 2) * 4 + 4;
+  len = GST_RTP_HEADER_LEN + GST_RTP_HEADER_CSRC_SIZE (buffer);
+  if (GST_RTP_HEADER_EXTENSION (buffer))
+    len += GST_READ_UINT16_BE (GST_BUFFER_DATA (buffer) + len + 2) * 4 + 4;
 
   return len;
 }
@@ -641,7 +528,10 @@
 guint8
 gst_rtp_buffer_get_version (GstBuffer * buffer)
 {
-  return GST_RTP_HEADER_VERSION (GST_BUFFER_DATA (buffer));
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
+
+  return GST_RTP_HEADER_VERSION (buffer);
 }
 
 /**
@@ -658,9 +548,11 @@
 void
 gst_rtp_buffer_set_version (GstBuffer * buffer, guint8 version)
 {
+  g_return_if_fail (GST_IS_BUFFER (buffer));
   g_return_if_fail (version < 0x04);
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
 
-  GST_RTP_HEADER_VERSION (GST_BUFFER_DATA (buffer)) = version;
+  GST_RTP_HEADER_VERSION (buffer) = version;
 }
 
 /**
@@ -678,7 +570,10 @@
 gboolean
 gst_rtp_buffer_get_padding (GstBuffer * buffer)
 {
-  return GST_RTP_HEADER_PADDING (GST_BUFFER_DATA (buffer));
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, FALSE);
+
+  return GST_RTP_HEADER_PADDING (buffer);
 }
 
 /**
@@ -695,7 +590,10 @@
 void
 gst_rtp_buffer_set_padding (GstBuffer * buffer, gboolean padding)
 {
-  GST_RTP_HEADER_PADDING (GST_BUFFER_DATA (buffer)) = padding;
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
+
+  GST_RTP_HEADER_PADDING (buffer) = padding;
 }
 
 /**
@@ -715,14 +613,13 @@
 void
 gst_rtp_buffer_pad_to (GstBuffer * buffer, guint len)
 {
-  guint8 *data;
-
-  data = GST_BUFFER_DATA (buffer);
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
 
   if (len > 0)
-    GST_RTP_HEADER_PADDING (data) = TRUE;
+    GST_RTP_HEADER_PADDING (buffer) = TRUE;
   else
-    GST_RTP_HEADER_PADDING (data) = FALSE;
+    GST_RTP_HEADER_PADDING (buffer) = FALSE;
 
   /* FIXME, set the padding byte at the end of the payload data */
 }
@@ -742,7 +639,10 @@
 gboolean
 gst_rtp_buffer_get_extension (GstBuffer * buffer)
 {
-  return GST_RTP_HEADER_EXTENSION (GST_BUFFER_DATA (buffer));
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, FALSE);
+
+  return GST_RTP_HEADER_EXTENSION (buffer);
 }
 
 /**
@@ -759,7 +659,10 @@
 void
 gst_rtp_buffer_set_extension (GstBuffer * buffer, gboolean extension)
 {
-  GST_RTP_HEADER_EXTENSION (GST_BUFFER_DATA (buffer)) = extension;
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
+
+  GST_RTP_HEADER_EXTENSION (buffer) = extension;
 }
 
 /**
@@ -791,14 +694,15 @@
   guint len;
   guint8 *pdata;
 
-  pdata = GST_BUFFER_DATA (buffer);
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, FALSE);
 
-  if (!GST_RTP_HEADER_EXTENSION (pdata))
+  if (!GST_RTP_HEADER_EXTENSION (buffer))
     return FALSE;
 
   /* move to the extension */
-  len = GST_RTP_HEADER_LEN + GST_RTP_HEADER_CSRC_SIZE (pdata);
-  pdata += len;
+  len = GST_RTP_HEADER_LEN + GST_RTP_HEADER_CSRC_SIZE (buffer);
+  pdata = GST_BUFFER_DATA (buffer) + len;
 
   if (bits)
     *bits = GST_READ_UINT16_BE (pdata);
@@ -836,32 +740,27 @@
   guint32 min_size = 0;
   guint8 *data;
 
-  data = GST_BUFFER_DATA (buffer);
-
-  /* check if the buffer is big enough to hold the extension */
-  min_size =
-      GST_RTP_HEADER_LEN + GST_RTP_HEADER_CSRC_SIZE (data) + 4 +
-      length * sizeof (guint32);
-  if (G_UNLIKELY (min_size > GST_BUFFER_SIZE (buffer)))
-    goto too_small;
-
-  /* now we can set the extension bit */
-  gst_rtp_buffer_set_extension (buffer, TRUE);
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, FALSE);
 
-  data += GST_RTP_HEADER_LEN + GST_RTP_HEADER_CSRC_SIZE (data);
-  GST_WRITE_UINT16_BE (data, bits);
-  GST_WRITE_UINT16_BE (data + 2, length);
-
-  return TRUE;
+  gst_rtp_buffer_set_extension (buffer, TRUE);
+  min_size =
+      GST_RTP_HEADER_LEN + GST_RTP_HEADER_CSRC_SIZE (buffer) + 4 +
+      length * sizeof (guint32);
 
-  /* ERRORS */
-too_small:
-  {
-    g_warning
-        ("rtp buffer too small: need more than %d bytes but only have %d bytes",
+  if (min_size > GST_BUFFER_SIZE (buffer)) {
+    GST_WARNING_OBJECT (buffer,
+        "rtp buffer too small: need more than %d bytes but only have %d bytes",
         min_size, GST_BUFFER_SIZE (buffer));
     return FALSE;
   }
+
+  data =
+      GST_BUFFER_DATA (buffer) + GST_RTP_HEADER_LEN +
+      GST_RTP_HEADER_CSRC_SIZE (buffer);
+  GST_WRITE_UINT16_BE (data, bits);
+  GST_WRITE_UINT16_BE (data + 2, length);
+  return TRUE;
 }
 
 /**
@@ -879,34 +778,10 @@
 guint32
 gst_rtp_buffer_get_ssrc (GstBuffer * buffer)
 {
-  return g_ntohl (GST_RTP_HEADER_SSRC (GST_BUFFER_DATA (buffer)));
-}
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
 
-/**
- * gst_rtp_buffer_list_get_ssrc:
- * @list: the buffer list
- *
- * Get the SSRC of the first RTP packet in @list.
- * All RTP packets within @list have the same SSRC.
- *
- * Returns: the SSRC of @list in host order.
- *
- * Since: 0.10.24
- */
- 
- #ifdef __SYMBIAN32__
-EXPORT_C
-#endif
-
-guint32
-gst_rtp_buffer_list_get_ssrc (GstBufferList * list)
-{
-  GstBuffer *buffer;
-
-  buffer = gst_buffer_list_get (list, 0, 0);
-  g_return_val_if_fail (buffer != NULL, 0);
-
-  return g_ntohl (GST_RTP_HEADER_SSRC (GST_BUFFER_DATA (buffer)));
+  return g_ntohl (GST_RTP_HEADER_SSRC (buffer));
 }
 
 /**
@@ -923,32 +798,10 @@
 void
 gst_rtp_buffer_set_ssrc (GstBuffer * buffer, guint32 ssrc)
 {
-  GST_RTP_HEADER_SSRC (GST_BUFFER_DATA (buffer)) = g_htonl (ssrc);
-}
-
-static GstBufferListItem
-set_ssrc_header (GstBuffer ** buffer, guint group, guint idx, guint32 * ssrc)
-{
-  GST_RTP_HEADER_SSRC (GST_BUFFER_DATA (*buffer)) = g_htonl (*ssrc);
-  return GST_BUFFER_LIST_SKIP_GROUP;
-}
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
 
-/**
- * gst_rtp_buffer_list_set_ssrc:
- * @list: the buffer list
- * @ssrc: the new SSRC
- *
- * Set the SSRC on each RTP packet in @list to @ssrc.
- *
- * Since: 0.10.24
- */
-#ifdef __SYMBIAN32__
-EXPORT_C
-#endif
-void
-gst_rtp_buffer_list_set_ssrc (GstBufferList * list, guint32 ssrc)
-{
-  gst_buffer_list_foreach (list, (GstBufferListFunc) set_ssrc_header, &ssrc);
+  GST_RTP_HEADER_SSRC (buffer) = g_htonl (ssrc);
 }
 
 /**
@@ -966,7 +819,10 @@
 guint8
 gst_rtp_buffer_get_csrc_count (GstBuffer * buffer)
 {
-  return GST_RTP_HEADER_CSRC_COUNT (GST_BUFFER_DATA (buffer));
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
+
+  return GST_RTP_HEADER_CSRC_COUNT (buffer);
 }
 
 /**
@@ -985,13 +841,11 @@
 guint32
 gst_rtp_buffer_get_csrc (GstBuffer * buffer, guint8 idx)
 {
-  guint8 *data;
-
-  data = GST_BUFFER_DATA (buffer);
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
+  g_return_val_if_fail (idx < GST_RTP_HEADER_CSRC_COUNT (buffer), 0);
 
-  g_return_val_if_fail (idx < GST_RTP_HEADER_CSRC_COUNT (data), 0);
-
-  return GST_READ_UINT32_BE (GST_RTP_HEADER_CSRC_LIST_OFFSET (data, idx));
+  return GST_READ_UINT32_BE (GST_RTP_HEADER_CSRC_LIST_OFFSET (buffer, idx));
 }
 
 /**
@@ -1009,13 +863,11 @@
 void
 gst_rtp_buffer_set_csrc (GstBuffer * buffer, guint8 idx, guint32 csrc)
 {
-  guint8 *data;
-
-  data = GST_BUFFER_DATA (buffer);
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
+  g_return_if_fail (idx < GST_RTP_HEADER_CSRC_COUNT (buffer));
 
-  g_return_if_fail (idx < GST_RTP_HEADER_CSRC_COUNT (data));
-
-  GST_WRITE_UINT32_BE (GST_RTP_HEADER_CSRC_LIST_OFFSET (data, idx), csrc);
+  GST_WRITE_UINT32_BE (GST_RTP_HEADER_CSRC_LIST_OFFSET (buffer, idx), csrc);
 }
 
 /**
@@ -1033,7 +885,10 @@
 gboolean
 gst_rtp_buffer_get_marker (GstBuffer * buffer)
 {
-  return GST_RTP_HEADER_MARKER (GST_BUFFER_DATA (buffer));
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, FALSE);
+
+  return GST_RTP_HEADER_MARKER (buffer);
 }
 
 /**
@@ -1050,7 +905,10 @@
 void
 gst_rtp_buffer_set_marker (GstBuffer * buffer, gboolean marker)
 {
-  GST_RTP_HEADER_MARKER (GST_BUFFER_DATA (buffer)) = marker;
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
+
+  GST_RTP_HEADER_MARKER (buffer) = marker;
 }
 
 /**
@@ -1068,34 +926,10 @@
 guint8
 gst_rtp_buffer_get_payload_type (GstBuffer * buffer)
 {
-  return GST_RTP_HEADER_PAYLOAD_TYPE (GST_BUFFER_DATA (buffer));
-}
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
 
-/**
- * gst_rtp_buffer_list_get_payload_type:
- * @list: the buffer list
- *
- * Get the payload type of the first RTP packet in @list.
- * All packets in @list should have the same payload type.
- *
- * Returns: The payload type.
- *
- * Since: 0.10.24
- */
- 
- #ifdef __SYMBIAN32__
-EXPORT_C
-#endif
-
-guint8
-gst_rtp_buffer_list_get_payload_type (GstBufferList * list)
-{
-  GstBuffer *buffer;
-
-  buffer = gst_buffer_list_get (list, 0, 0);
-  g_return_val_if_fail (buffer != NULL, 0);
-
-  return GST_RTP_HEADER_PAYLOAD_TYPE (GST_BUFFER_DATA (buffer));
+  return GST_RTP_HEADER_PAYLOAD_TYPE (buffer);
 }
 
 /**
@@ -1112,39 +946,11 @@
 void
 gst_rtp_buffer_set_payload_type (GstBuffer * buffer, guint8 payload_type)
 {
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
   g_return_if_fail (payload_type < 0x80);
 
-  GST_RTP_HEADER_PAYLOAD_TYPE (GST_BUFFER_DATA (buffer)) = payload_type;
-}
-
-static GstBufferListItem
-set_pt_header (GstBuffer ** buffer, guint group, guint idx, guint8 * pt)
-{
-  GST_RTP_HEADER_PAYLOAD_TYPE (GST_BUFFER_DATA (*buffer)) = *pt;
-  return GST_BUFFER_LIST_SKIP_GROUP;
-}
-
-/**
- * gst_rtp_buffer_list_set_payload_type:
- * @list: the buffer list
- * @payload_type: the new type
- *
- * Set the payload type of each RTP packet in @list to @payload_type.
- *
- * Since: 0.10.24
- */
- 
-#ifdef __SYMBIAN32__
-EXPORT_C
-#endif
- 
-void
-gst_rtp_buffer_list_set_payload_type (GstBufferList * list, guint8 payload_type)
-{
-  g_return_if_fail (payload_type < 0x80);
-
-  gst_buffer_list_foreach (list, (GstBufferListFunc) set_pt_header,
-      &payload_type);
+  GST_RTP_HEADER_PAYLOAD_TYPE (buffer) = payload_type;
 }
 
 /**
@@ -1162,7 +968,10 @@
 guint16
 gst_rtp_buffer_get_seq (GstBuffer * buffer)
 {
-  return g_ntohs (GST_RTP_HEADER_SEQ (GST_BUFFER_DATA (buffer)));
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
+
+  return g_ntohs (GST_RTP_HEADER_SEQ (buffer));
 }
 
 /**
@@ -1179,69 +988,13 @@
 void
 gst_rtp_buffer_set_seq (GstBuffer * buffer, guint16 seq)
 {
-  GST_RTP_HEADER_SEQ (GST_BUFFER_DATA (buffer)) = g_htons (seq);
-}
-
-static GstBufferListItem
-set_seq_header (GstBuffer ** buffer, guint group, guint idx, guint16 * seq)
-{
-  GST_RTP_HEADER_SEQ (GST_BUFFER_DATA (*buffer)) = g_htons (*seq);
-  (*seq)++;
-  return GST_BUFFER_LIST_SKIP_GROUP;
-}
-
-/**
- * gst_rtp_buffer_list_set_seq:
- * @list: the buffer list
- * @seq: the new sequence number
- *
- * Set the sequence number of each RTP packet in @list to @seq.
- *
- * Returns: The seq number of the last packet in the list + 1.
- *
- * Since: 0.10.24
- */
- 
- #ifdef __SYMBIAN32__
-EXPORT_C
-#endif
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
 
-guint16
-gst_rtp_buffer_list_set_seq (GstBufferList * list, guint16 seq)
-{
-  gst_buffer_list_foreach (list, (GstBufferListFunc) set_seq_header, &seq);
-  return seq;
+  GST_RTP_HEADER_SEQ (buffer) = g_htons (seq);
 }
 
 /**
- * gst_rtp_buffer_list_get_seq:
- * @list: the buffer list
- *
- * Get the sequence number of the first RTP packet in @list.
- * All packets within @list have the same sequence number.
- *
- * Returns: The seq number
- *
- * Since: 0.10.24
- */
- 
-#ifdef __SYMBIAN32__
-EXPORT_C
-#endif
- 
-guint16
-gst_rtp_buffer_list_get_seq (GstBufferList * list)
-{
-  GstBuffer *buffer;
-
-  buffer = gst_buffer_list_get (list, 0, 0);
-  g_return_val_if_fail (buffer != NULL, 0);
-
-  return g_ntohl (GST_RTP_HEADER_SEQ (GST_BUFFER_DATA (buffer)));
-}
-
-
-/**
  * gst_rtp_buffer_get_timestamp:
  * @buffer: the buffer
  *
@@ -1256,34 +1009,10 @@
 guint32
 gst_rtp_buffer_get_timestamp (GstBuffer * buffer)
 {
-  return g_ntohl (GST_RTP_HEADER_TIMESTAMP (GST_BUFFER_DATA (buffer)));
-}
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
 
-/**
- * gst_rtp_buffer_list_get_timestamp:
- * @list: the buffer list
- *
- * Get the timestamp of the first RTP packet in @list.
- * All packets within @list have the same timestamp.
- *
- * Returns: The timestamp in host order.
- *
- * Since: 0.10.24
- */
- 
- #ifdef __SYMBIAN32__
-EXPORT_C
-#endif
-
-guint32
-gst_rtp_buffer_list_get_timestamp (GstBufferList * list)
-{
-  GstBuffer *buffer;
-
-  buffer = gst_buffer_list_get (list, 0, 0);
-  g_return_val_if_fail (buffer != NULL, 0);
-
-  return g_ntohl (GST_RTP_HEADER_TIMESTAMP (GST_BUFFER_DATA (buffer)));
+  return g_ntohl (GST_RTP_HEADER_TIMESTAMP (buffer));
 }
 
 /**
@@ -1300,37 +1029,10 @@
 void
 gst_rtp_buffer_set_timestamp (GstBuffer * buffer, guint32 timestamp)
 {
-  GST_RTP_HEADER_TIMESTAMP (GST_BUFFER_DATA (buffer)) = g_htonl (timestamp);
-}
-
-
-static GstBufferListItem
-set_timestamp_header (GstBuffer ** buffer, guint group, guint idx,
-    guint32 * timestamp)
-{
-  GST_RTP_HEADER_TIMESTAMP (GST_BUFFER_DATA (*buffer)) = g_htonl (*timestamp);
-  return GST_BUFFER_LIST_SKIP_GROUP;
-}
+  g_return_if_fail (GST_IS_BUFFER (buffer));
+  g_return_if_fail (GST_BUFFER_DATA (buffer) != NULL);
 
-/**
- * gst_rtp_buffer_list_set_timestamp:
- * @list: the buffer list
- * @timestamp: the new timestamp
- *
- * Set the timestamp of each RTP packet in @list to @timestamp.
- *
- * Since: 0.10.24
- */
- 
- #ifdef __SYMBIAN32__
-EXPORT_C
-#endif
-
-void
-gst_rtp_buffer_list_set_timestamp (GstBufferList * list, guint32 timestamp)
-{
-  gst_buffer_list_foreach (list, (GstBufferListFunc) set_timestamp_header,
-      &timestamp);
+  GST_RTP_HEADER_TIMESTAMP (buffer) = g_htonl (timestamp);
 }
 
 /**
@@ -1357,10 +1059,15 @@
 {
   guint poffset, plen;
 
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, NULL);
+
   plen = gst_rtp_buffer_get_payload_len (buffer);
   /* we can't go past the length */
-  if (G_UNLIKELY (offset >= plen))
-    goto wrong_offset;
+  if (G_UNLIKELY (offset >= plen)) {
+    GST_WARNING ("offset=%u should be less then plen=%u", offset, plen);
+    return (NULL);
+  }
 
   /* apply offset */
   poffset = gst_rtp_buffer_get_header_len (buffer) + offset;
@@ -1371,13 +1078,6 @@
     plen = len;
 
   return gst_buffer_create_sub (buffer, poffset, plen);
-
-  /* ERRORS */
-wrong_offset:
-  {
-    g_warning ("offset=%u should be less then plen=%u", offset, plen);
-    return NULL;
-  }
 }
 
 /**
@@ -1416,58 +1116,16 @@
 gst_rtp_buffer_get_payload_len (GstBuffer * buffer)
 {
   guint len, size;
-  guint8 *data;
+
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, 0);
 
   size = GST_BUFFER_SIZE (buffer);
-  data = GST_BUFFER_DATA (buffer);
 
   len = size - gst_rtp_buffer_get_header_len (buffer);
 
-  if (GST_RTP_HEADER_PADDING (data))
-    len -= data[size - 1];
-
-  return len;
-}
-
-/**
- * gst_rtp_buffer_list_get_payload_len:
- * @list: the buffer list
- *
- * Get the length of the payload of the RTP packet in @list.
- *
- * Returns: The length of the payload in @list.
- *
- * Since: 0.10.24
- */
- 
-#ifdef __SYMBIAN32__
-EXPORT_C
-#endif
- 
-guint
-gst_rtp_buffer_list_get_payload_len (GstBufferList * list)
-{
-  guint len;
-  GstBufferListIterator *it;
-
-  it = gst_buffer_list_iterate (list);
-  len = 0;
-
-  while (gst_buffer_list_iterator_next_group (it)) {
-    guint i;
-    GstBuffer *buf;
-
-    i = 0;
-    while ((buf = gst_buffer_list_iterator_next (it))) {
-      /* skip the RTP header */
-      if (!i++)
-        continue;
-      /* take the size of the current buffer */
-      len += GST_BUFFER_SIZE (buf);
-    }
-  }
-
-  gst_buffer_list_iterator_free (it);
+  if (GST_RTP_HEADER_PADDING (buffer))
+    len -= GST_BUFFER_DATA (buffer)[size - 1];
 
   return len;
 }
@@ -1488,6 +1146,9 @@
 gpointer
 gst_rtp_buffer_get_payload (GstBuffer * buffer)
 {
+  g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
+  g_return_val_if_fail (GST_BUFFER_DATA (buffer) != NULL, NULL);
+
   return GST_BUFFER_DATA (buffer) + gst_rtp_buffer_get_header_len (buffer);
 }
 
@@ -1529,11 +1190,10 @@
  * @seqnum1: a sequence number
  * @seqnum2: a sequence number
  *
- * Compare two sequence numbers, taking care of wraparounds. This function
- * returns the difference between @seqnum1 and @seqnum2.
+ * Compare two sequence numbers, taking care of wraparounds.
  *
- * Returns: a negative value if @seqnum1 is bigger than @seqnum2, 0 if they
- * are equal or a positive value if @seqnum1 is smaller than @segnum2.
+ * Returns: -1 if @seqnum1 is before @seqnum2, 0 if they are equal or 1 if
+ * @seqnum1 is bigger than @segnum2.
  *
  * Since: 0.10.15
  */
@@ -1544,7 +1204,13 @@
 gint
 gst_rtp_buffer_compare_seqnum (guint16 seqnum1, guint16 seqnum2)
 {
-  return (gint16) (seqnum2 - seqnum1);
+  /* check if diff more than half of the 16bit range */
+  if (abs (seqnum2 - seqnum1) > (1 << 15)) {
+    /* one of a/b has wrapped */
+    return seqnum1 - seqnum2;
+  } else {
+    return seqnum2 - seqnum1;
+  }
 }
 
 /**