static GstStateChangeReturn
gst_rtp_mpv_depay_change_state (GstElement * element, GstStateChange transition)
{
GstRtpMPVDepay *rtpmpvdepay;
GstStateChangeReturn ret;
rtpmpvdepay = GST_RTP_MPV_DEPAY (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_NULL:
break;
default:
break;
}
return ret;
}
static gboolean
gst_rtp_mpv_depay_setcaps (GstBaseRTPDepayload * depayload, GstCaps * caps)
{
GstStructure *structure;
GstRtpMPVDepay *rtpmpvdepay;
gint clock_rate;
GstCaps *outcaps;
gboolean res;
rtpmpvdepay = GST_RTP_MPV_DEPAY (depayload);
structure = gst_caps_get_structure (caps, 0);
if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
clock_rate = 90000; /* default */
depayload->clock_rate = clock_rate;
outcaps = gst_caps_new_simple ("video/mpeg",
"mpegversion", G_TYPE_INT, 2,
"systemstream", G_TYPE_BOOLEAN, FALSE, NULL);
res = gst_pad_set_caps (depayload->srcpad, outcaps);
gst_caps_unref (outcaps);
return res;
}
static GstBuffer *
gst_rtp_mpv_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
{
GstRtpMPVDepay *rtpmpvdepay;
GstBuffer *outbuf;
rtpmpvdepay = GST_RTP_MPV_DEPAY (depayload);
{
gint payload_len, payload_header;
guint8 *payload;
guint8 T;
payload_len = gst_rtp_buffer_get_payload_len (buf);
payload = gst_rtp_buffer_get_payload (buf);
payload_header = 0;
if (payload_len <= 4)
goto empty_packet;
/* 3.4 MPEG Video-specific header
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | MBZ |T| TR | |N|S|B|E| P | | BFC | | FFC |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* AN FBV FFV
*/
T = (payload[0] & 0x04);
payload_len -= 4;
payload_header += 4;
payload += 4;
if (T) {
/*
* 3.4.1 MPEG-2 Video-specific header extension
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |X|E|f_[0,0]|f_[0,1]|f_[1,0]|f_[1,1]| DC| PS|T|P|C|Q|V|A|R|H|G|D|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
if (payload_len <= 4)
goto empty_packet;
payload_len -= 4;
payload_header += 4;
payload += 4;
}
outbuf = gst_rtp_buffer_get_payload_subbuffer (buf, payload_header, -1);
GST_DEBUG_OBJECT (rtpmpvdepay,
"gst_rtp_mpv_depay_chain: pushing buffer of size %d",
GST_BUFFER_SIZE (outbuf));
return outbuf;
}
return NULL;
/* ERRORS */
empty_packet:
{
GST_ELEMENT_WARNING (rtpmpvdepay, STREAM, DECODE,
(NULL), ("Empty payload."));
return NULL;
}
}
static GstBuffer *
gst_rtp_mpv_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp)
{
GstRtpMPVDepay *rtpmpvdepay;
GstBuffer *outbuf = NULL;
rtpmpvdepay = GST_RTP_MPV_DEPAY (depayload);
{
gint payload_len, payload_header;
guint8 *payload;
guint8 T;
payload_len = gst_rtp_buffer_get_payload_len (rtp);
payload = gst_rtp_buffer_get_payload (rtp);
payload_header = 0;
if (payload_len <= 4)
goto empty_packet;
/* 3.4 MPEG Video-specific header
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | MBZ |T| TR | |N|S|B|E| P | | BFC | | FFC |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* AN FBV FFV
*/
T = (payload[0] & 0x04);
payload_len -= 4;
payload_header += 4;
payload += 4;
if (T) {
/*
* 3.4.1 MPEG-2 Video-specific header extension
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |X|E|f_[0,0]|f_[0,1]|f_[1,0]|f_[1,1]| DC| PS|T|P|C|Q|V|A|R|H|G|D|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
if (payload_len <= 4)
goto empty_packet;
payload_len -= 4;
payload_header += 4;
payload += 4;
}
outbuf = gst_rtp_buffer_get_payload_subbuffer (rtp, payload_header, -1);
if (outbuf) {
GST_DEBUG_OBJECT (rtpmpvdepay,
"gst_rtp_mpv_depay_chain: pushing buffer of size %" G_GSIZE_FORMAT,
gst_buffer_get_size (outbuf));
gst_rtp_drop_meta (GST_ELEMENT_CAST (rtpmpvdepay), outbuf,
g_quark_from_static_string (GST_META_TAG_VIDEO_STR));
}
}
return outbuf;
/* ERRORS */
empty_packet:
{
GST_ELEMENT_WARNING (rtpmpvdepay, STREAM, DECODE,
(NULL), ("Empty payload."));
return NULL;
}
}
