/* GStreamer * Copyright (C) <2006> Wim Taymans <wim.taymans@gmail.com> * * 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., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include <gst/rtp/gstrtpbuffer.h> #include <gst/video/video.h> #include <string.h> #include "gstrtpmpvdepay.h" #include "gstrtputils.h" GST_DEBUG_CATEGORY_STATIC (rtpmpvdepay_debug); #define GST_CAT_DEFAULT (rtpmpvdepay_debug) /* FIXME, we set the mpeg version to 2, we should ideally be looking at contents * of the stream to figure out the version */ static GstStaticPadTemplate gst_rtp_mpv_depay_src_template = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/mpeg, mpegversion = (int) 2, systemstream = (boolean) FALSE") ); static GstStaticPadTemplate gst_rtp_mpv_depay_sink_template = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("application/x-rtp, " "media = (string) \"video\", " "clock-rate = (int) 90000, " "encoding-name = (string) \"MPV\";" "application/x-rtp, " "media = (string) \"video\", " "payload = (int) " GST_RTP_PAYLOAD_MPV_STRING ", " "clock-rate = (int) 90000") ); G_DEFINE_TYPE (GstRtpMPVDepay, gst_rtp_mpv_depay, GST_TYPE_RTP_BASE_DEPAYLOAD); static gboolean gst_rtp_mpv_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps); static GstBuffer *gst_rtp_mpv_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp); static void gst_rtp_mpv_depay_class_init (GstRtpMPVDepayClass * klass) { GstElementClass *gstelement_class; GstRTPBaseDepayloadClass *gstrtpbasedepayload_class; gstelement_class = (GstElementClass *) klass; gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass; gst_element_class_add_static_pad_template (gstelement_class, &gst_rtp_mpv_depay_src_template); gst_element_class_add_static_pad_template (gstelement_class, &gst_rtp_mpv_depay_sink_template); gst_element_class_set_static_metadata (gstelement_class, "RTP MPEG video depayloader", "Codec/Depayloader/Network/RTP", "Extracts MPEG video from RTP packets (RFC 2250)", "Wim Taymans <wim.taymans@gmail.com>"); gstrtpbasedepayload_class->set_caps = gst_rtp_mpv_depay_setcaps; gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_mpv_depay_process; GST_DEBUG_CATEGORY_INIT (rtpmpvdepay_debug, "rtpmpvdepay", 0, "MPEG Video RTP Depayloader"); } static void gst_rtp_mpv_depay_init (GstRtpMPVDepay * rtpmpvdepay) { } static gboolean gst_rtp_mpv_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps) { GstStructure *structure; gint clock_rate; GstCaps *outcaps; gboolean res; 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 (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_non_video_meta (rtpmpvdepay, outbuf); } } return outbuf; /* ERRORS */ empty_packet: { GST_ELEMENT_WARNING (rtpmpvdepay, STREAM, DECODE, (NULL), ("Empty payload.")); return NULL; } } gboolean gst_rtp_mpv_depay_plugin_init (GstPlugin * plugin) { return gst_element_register (plugin, "rtpmpvdepay", GST_RANK_SECONDARY, GST_TYPE_RTP_MPV_DEPAY); }