/* GStreamer * Copyright (C) <2005> Wim Taymans * * 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. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include "gstrtpmp4gdepay.h" GST_DEBUG_CATEGORY_STATIC (rtpmp4gdepay_debug); #define GST_CAT_DEFAULT (rtpmp4gdepay_debug) /* elementfactory information */ static const GstElementDetails gst_rtp_mp4gdepay_details = GST_ELEMENT_DETAILS ("RTP packet depayloader", "Codec/Depayloader/Network", "Extracts MPEG4 elementary streams from RTP packets (RFC 3640)", "Wim Taymans "); static GstStaticPadTemplate gst_rtp_mp4g_depay_src_template = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/mpeg," "mpegversion=(int) 4," "systemstream=(boolean)false;" "audio/mpeg," "mpegversion=(int) 4") ); static GstStaticPadTemplate gst_rtp_mp4g_depay_sink_template = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("application/x-rtp, " "media = (string) { \"video\", \"audio\", \"application\" }, " "payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", " "clock-rate = (int) [1, MAX ], " "encoding-name = (string) \"MPEG4-GENERIC\", " /* required string params */ "streamtype = (string) { \"4\", \"5\" }, " /* 4 = video, 5 = audio */ /* "profile-level-id = (string) [1,MAX], " */ /* "config = (string) [1,MAX]" */ "mode = (string) { \"generic\", \"CELP-cbr\", \"CELP-vbr\", \"AAC-lbr\", \"AAC-hbr\" } " /* Optional general parameters */ /* "objecttype = (string) [1,MAX], " */ /* "constantsize = (string) [1,MAX], " *//* constant size of each AU */ /* "constantduration = (string) [1,MAX], " *//* constant duration of each AU */ /* "maxdisplacement = (string) [1,MAX], " */ /* "de-interleavebuffersize = (string) [1,MAX], " */ /* Optional configuration parameters */ /* "sizelength = (string) [1, 32], " */ /* "indexlength = (string) [1, 32], " */ /* "indexdeltalength = (string) [1, 32], " */ /* "ctsdeltalength = (string) [1, 32], " */ /* "dtsdeltalength = (string) [1, 32], " */ /* "randomaccessindication = (string) {0, 1}, " */ /* "streamstateindication = (string) [0, 32], " */ /* "auxiliarydatasizelength = (string) [0, 32]" */ ) ); /* simple bitstream parser */ typedef struct { const guint8 *data; const guint8 *end; gint head; /* bitpos in the cache of next bit */ guint64 cache; /* cached bytes */ } GstBsParse; static void gst_bs_parse_init (GstBsParse * bs, const guint8 * data, guint size) { bs->data = data; bs->end = data + size; bs->head = 0; bs->cache = 0xffffffff; } static guint32 gst_bs_parse_read (GstBsParse * bs, guint n) { guint32 res = 0; gint shift; if (n == 0) return res; /* fill up the cache if we need to */ while (bs->head < n) { if (bs->data >= bs->end) { /* we're at the end, can't produce more than head number of bits */ n = bs->head; break; } /* shift bytes in cache, moving the head bits of the cache left */ bs->cache = (bs->cache << 8) | *bs->data++; bs->head += 8; } /* bring the required bits down and truncate */ if ((shift = bs->head - n) > 0) res = bs->cache >> shift; else res = bs->cache; /* mask out required bits */ if (n < 32) res &= (1 << n) - 1; bs->head = shift; return res; } GST_BOILERPLATE (GstRtpMP4GDepay, gst_rtp_mp4g_depay, GstBaseRTPDepayload, GST_TYPE_BASE_RTP_DEPAYLOAD); static void gst_rtp_mp4g_depay_finalize (GObject * object); static gboolean gst_rtp_mp4g_depay_setcaps (GstBaseRTPDepayload * depayload, GstCaps * caps); static GstBuffer *gst_rtp_mp4g_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf); static GstStateChangeReturn gst_rtp_mp4g_depay_change_state (GstElement * element, GstStateChange transition); static void gst_rtp_mp4g_depay_base_init (gpointer klass) { GstElementClass *element_class = GST_ELEMENT_CLASS (klass); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&gst_rtp_mp4g_depay_src_template)); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&gst_rtp_mp4g_depay_sink_template)); gst_element_class_set_details (element_class, &gst_rtp_mp4gdepay_details); } static void gst_rtp_mp4g_depay_class_init (GstRtpMP4GDepayClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; GstBaseRTPDepayloadClass *gstbasertpdepayload_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; gstbasertpdepayload_class = (GstBaseRTPDepayloadClass *) klass; parent_class = g_type_class_peek_parent (klass); gobject_class->finalize = gst_rtp_mp4g_depay_finalize; gstelement_class->change_state = gst_rtp_mp4g_depay_change_state; gstbasertpdepayload_class->process = gst_rtp_mp4g_depay_process; gstbasertpdepayload_class->set_caps = gst_rtp_mp4g_depay_setcaps; GST_DEBUG_CATEGORY_INIT (rtpmp4gdepay_debug, "rtpmp4gdepay", 0, "MP4-generic RTP Depayloader"); } static void gst_rtp_mp4g_depay_init (GstRtpMP4GDepay * rtpmp4gdepay, GstRtpMP4GDepayClass * klass) { rtpmp4gdepay->adapter = gst_adapter_new (); rtpmp4gdepay->packets = g_queue_new (); } static void gst_rtp_mp4g_depay_finalize (GObject * object) { GstRtpMP4GDepay *rtpmp4gdepay; rtpmp4gdepay = GST_RTP_MP4G_DEPAY (object); g_object_unref (rtpmp4gdepay->adapter); rtpmp4gdepay->adapter = NULL; g_queue_free (rtpmp4gdepay->packets); rtpmp4gdepay->packets = NULL; G_OBJECT_CLASS (parent_class)->finalize (object); } static gint gst_rtp_mp4g_depay_parse_int (GstStructure * structure, const gchar * field, gint def) { const gchar *str; gint res; if ((str = gst_structure_get_string (structure, field))) return atoi (str); if (gst_structure_get_int (structure, field, &res)) return res; return def; } static gboolean gst_rtp_mp4g_depay_setcaps (GstBaseRTPDepayload * depayload, GstCaps * caps) { GstStructure *structure; GstRtpMP4GDepay *rtpmp4gdepay; GstCaps *srccaps = NULL; const gchar *str; gint clock_rate; gint someint; gboolean res; rtpmp4gdepay = GST_RTP_MP4G_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; if ((str = gst_structure_get_string (structure, "media"))) { if (strcmp (str, "audio") == 0) { srccaps = gst_caps_new_simple ("audio/mpeg", "mpegversion", G_TYPE_INT, 4, NULL); /* AAC always has a default constant duration of 1024 but it can be * overriden below. */ rtpmp4gdepay->constantDuration = 1024; } else if (strcmp (str, "video") == 0) { srccaps = gst_caps_new_simple ("video/mpeg", "mpegversion", G_TYPE_INT, 4, "systemstream", G_TYPE_BOOLEAN, FALSE, NULL); rtpmp4gdepay->constantDuration = 0; } } if (srccaps == NULL) goto unknown_media; /* these values are optional and have a default value of 0 (no header) */ rtpmp4gdepay->sizelength = gst_rtp_mp4g_depay_parse_int (structure, "sizelength", 0); rtpmp4gdepay->indexlength = gst_rtp_mp4g_depay_parse_int (structure, "indexlength", 0); rtpmp4gdepay->indexdeltalength = gst_rtp_mp4g_depay_parse_int (structure, "indexdeltalength", 0); rtpmp4gdepay->ctsdeltalength = gst_rtp_mp4g_depay_parse_int (structure, "ctsdeltalength", 0); rtpmp4gdepay->dtsdeltalength = gst_rtp_mp4g_depay_parse_int (structure, "dtsdeltalength", 0); someint = gst_rtp_mp4g_depay_parse_int (structure, "randomaccessindication", 0); rtpmp4gdepay->randomaccessindication = someint > 0 ? 1 : 0; rtpmp4gdepay->streamstateindication = gst_rtp_mp4g_depay_parse_int (structure, "streamstateindication", 0); rtpmp4gdepay->auxiliarydatasizelength = gst_rtp_mp4g_depay_parse_int (structure, "auxiliarydatasizelength", 0); rtpmp4gdepay->constantSize = gst_rtp_mp4g_depay_parse_int (structure, "constantsize", 0); rtpmp4gdepay->constantDuration = gst_rtp_mp4g_depay_parse_int (structure, "constantduration", rtpmp4gdepay->constantDuration); /* get config string */ if ((str = gst_structure_get_string (structure, "config"))) { GValue v = { 0 }; g_value_init (&v, GST_TYPE_BUFFER); if (gst_value_deserialize (&v, str)) { GstBuffer *buffer; buffer = gst_value_get_buffer (&v); gst_caps_set_simple (srccaps, "codec_data", GST_TYPE_BUFFER, buffer, NULL); g_value_unset (&v); } else { g_warning ("cannot convert config to buffer"); } } res = gst_pad_set_caps (depayload->srcpad, srccaps); gst_caps_unref (srccaps); return res; /* ERRORS */ unknown_media: { GST_DEBUG_OBJECT (rtpmp4gdepay, "Unknown media type"); return FALSE; } } static void gst_rtp_mp4g_depay_clear_queue (GstRtpMP4GDepay * rtpmp4gdepay) { GstBuffer *outbuf; while ((outbuf = g_queue_pop_head (rtpmp4gdepay->packets))) gst_buffer_unref (outbuf); } static void gst_rtp_mp4g_depay_flush_queue (GstRtpMP4GDepay * rtpmp4gdepay) { GstBuffer *outbuf; gboolean discont = FALSE; guint AU_index; while ((outbuf = g_queue_pop_head (rtpmp4gdepay->packets))) { AU_index = GST_BUFFER_OFFSET (outbuf); GST_DEBUG_OBJECT (rtpmp4gdepay, "next available AU_index %u", AU_index); if (rtpmp4gdepay->next_AU_index != AU_index) { GST_DEBUG_OBJECT (rtpmp4gdepay, "discont, expected AU_index %u", rtpmp4gdepay->next_AU_index); discont = TRUE; } if (discont) { GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DISCONT); discont = FALSE; } GST_DEBUG_OBJECT (rtpmp4gdepay, "pushing AU_index %u", AU_index); gst_base_rtp_depayload_push (GST_BASE_RTP_DEPAYLOAD (rtpmp4gdepay), outbuf); rtpmp4gdepay->next_AU_index = AU_index + 1; } } static void gst_rtp_mp4g_depay_queue (GstRtpMP4GDepay * rtpmp4gdepay, GstBuffer * outbuf) { guint AU_index = GST_BUFFER_OFFSET (outbuf); if (rtpmp4gdepay->next_AU_index == -1) { GST_DEBUG_OBJECT (rtpmp4gdepay, "Init AU counter %u", AU_index); rtpmp4gdepay->next_AU_index = AU_index; } if (rtpmp4gdepay->next_AU_index == AU_index) { GST_DEBUG_OBJECT (rtpmp4gdepay, "pushing expected AU_index %u", AU_index); /* we received the expected packet, push it and flush as much as we can from * the queue */ gst_base_rtp_depayload_push (GST_BASE_RTP_DEPAYLOAD (rtpmp4gdepay), outbuf); rtpmp4gdepay->next_AU_index++; while ((outbuf = g_queue_peek_head (rtpmp4gdepay->packets))) { AU_index = GST_BUFFER_OFFSET (outbuf); GST_DEBUG_OBJECT (rtpmp4gdepay, "next available AU_index %u", AU_index); if (rtpmp4gdepay->next_AU_index == AU_index) { GST_DEBUG_OBJECT (rtpmp4gdepay, "pushing expected AU_index %u", AU_index); outbuf = g_queue_pop_head (rtpmp4gdepay->packets); gst_base_rtp_depayload_push (GST_BASE_RTP_DEPAYLOAD (rtpmp4gdepay), outbuf); rtpmp4gdepay->next_AU_index++; } else { GST_DEBUG_OBJECT (rtpmp4gdepay, "waiting for next AU_index %u", rtpmp4gdepay->next_AU_index); break; } } } else { GList *list; GST_DEBUG_OBJECT (rtpmp4gdepay, "queueing AU_index %u", AU_index); /* loop the list to skip strictly smaller AU_index buffers */ for (list = rtpmp4gdepay->packets->head; list; list = g_list_next (list)) { guint idx; gint gap; idx = GST_BUFFER_OFFSET (GST_BUFFER_CAST (list->data)); /* compare the new seqnum to the one in the buffer */ gap = (gint) (idx - AU_index); GST_DEBUG_OBJECT (rtpmp4gdepay, "compare with AU_index %u, gap %d", idx, gap); /* AU_index <= idx, we can stop looking */ if (G_LIKELY (gap > 0)) break; } if (G_LIKELY (list)) g_queue_insert_before (rtpmp4gdepay->packets, list, outbuf); else g_queue_push_tail (rtpmp4gdepay->packets, outbuf); } } static GstBuffer * gst_rtp_mp4g_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf) { GstRtpMP4GDepay *rtpmp4gdepay; GstBuffer *outbuf; GstClockTime timestamp; rtpmp4gdepay = GST_RTP_MP4G_DEPAY (depayload); /* flush remaining data on discont */ if (GST_BUFFER_IS_DISCONT (buf)) { GST_DEBUG_OBJECT (rtpmp4gdepay, "received DISCONT"); gst_adapter_clear (rtpmp4gdepay->adapter); } timestamp = GST_BUFFER_TIMESTAMP (buf); { gint payload_len, payload_AU; guint8 *payload; guint32 rtptime; guint AU_headers_len; guint AU_size, AU_index, AU_index_delta, payload_AU_size; gboolean M; payload_len = gst_rtp_buffer_get_payload_len (buf); payload = gst_rtp_buffer_get_payload (buf); rtptime = gst_rtp_buffer_get_timestamp (buf); M = gst_rtp_buffer_get_marker (buf); if (rtpmp4gdepay->sizelength > 0) { gint num_AU_headers, AU_headers_bytes, i; GstBsParse bs; if (payload_len < 2) goto short_payload; /* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- .. -+-+-+-+-+-+-+-+-+-+ * |AU-headers-length|AU-header|AU-header| |AU-header|padding| * | | (1) | (2) | | (n) * | bits | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- .. -+-+-+-+-+-+-+-+-+-+ * * The length is 2 bytes and contains the length of the following * AU-headers in bits. */ AU_headers_len = (payload[0] << 8) | payload[1]; AU_headers_bytes = (AU_headers_len + 7) / 8; num_AU_headers = AU_headers_len / 16; GST_DEBUG_OBJECT (rtpmp4gdepay, "AU headers len %d, bytes %d, num %d", AU_headers_len, AU_headers_bytes, num_AU_headers); /* skip header */ payload += 2; payload_len -= 2; if (payload_len < AU_headers_bytes) goto short_payload; /* skip special headers, point to first payload AU */ payload_AU = 2 + AU_headers_bytes; payload_AU_size = payload_len - AU_headers_bytes; /* point the bitstream parser to the first AU header bit */ gst_bs_parse_init (&bs, payload, payload_len); AU_index = AU_index_delta = 0; for (i = 0; i < num_AU_headers && payload_AU_size > 0; i++) { /* parse AU header * +---------------------------------------+ * | AU-size | * +---------------------------------------+ * | AU-Index / AU-Index-delta | * +---------------------------------------+ * | CTS-flag | * +---------------------------------------+ * | CTS-delta | * +---------------------------------------+ * | DTS-flag | * +---------------------------------------+ * | DTS-delta | * +---------------------------------------+ * | RAP-flag | * +---------------------------------------+ * | Stream-state | * +---------------------------------------+ */ AU_size = gst_bs_parse_read (&bs, rtpmp4gdepay->sizelength); /* calculate the AU_index, which is only on the first AU of the packet * and the AU_index_delta on the other AUs. This will be used to * reconstruct the AU ordering when interleaving. */ if (i == 0) { AU_index = gst_bs_parse_read (&bs, rtpmp4gdepay->indexlength); if (AU_index == 0 && rtpmp4gdepay->prev_AU_index == 0) { gint diff; /* if we see two consecutive packets with AU_index of 0, we can * assume we have constantDuration packets. Since we don't have * the index we must use the AU duration to calculate the * index. Get the diff between the timestamps first, this can be * positive or negative. */ if (rtpmp4gdepay->prev_rtptime <= rtptime) diff = rtptime - rtpmp4gdepay->prev_rtptime; else diff = -(rtpmp4gdepay->prev_rtptime - rtptime); /* get the number of packets by dividing with the duration */ diff /= rtpmp4gdepay->constantDuration; rtpmp4gdepay->last_AU_index += diff; rtpmp4gdepay->prev_AU_index = AU_index; AU_index = rtpmp4gdepay->last_AU_index; } else { rtpmp4gdepay->prev_AU_index = AU_index; rtpmp4gdepay->last_AU_index = AU_index; } /* keep track of the higest AU_index */ if (rtpmp4gdepay->max_AU_index != -1 && rtpmp4gdepay->max_AU_index <= AU_index) { GST_DEBUG_OBJECT (rtpmp4gdepay, "new interleave group, flushing"); /* a new interleave group started, flush */ gst_rtp_mp4g_depay_flush_queue (rtpmp4gdepay); } rtpmp4gdepay->prev_rtptime = rtptime; } else { AU_index_delta = gst_bs_parse_read (&bs, rtpmp4gdepay->indexdeltalength); AU_index += AU_index_delta + 1; } /* keep track of highest AU_index */ if (rtpmp4gdepay->max_AU_index == -1 || AU_index > rtpmp4gdepay->max_AU_index) rtpmp4gdepay->max_AU_index = AU_index; /* the presentation time offset, a 2s-complement value, we need this to * calculate the timestamp on the output packet. */ if (rtpmp4gdepay->ctsdeltalength > 0) { if (gst_bs_parse_read (&bs, 1)) gst_bs_parse_read (&bs, rtpmp4gdepay->ctsdeltalength); } /* the decoding time offset, a 2s-complement value */ if (rtpmp4gdepay->dtsdeltalength > 0) { if (gst_bs_parse_read (&bs, 1)) gst_bs_parse_read (&bs, rtpmp4gdepay->dtsdeltalength); } /* RAP-flag to indicate that the AU contains a keyframe */ if (rtpmp4gdepay->randomaccessindication) gst_bs_parse_read (&bs, 1); /* stream-state */ if (rtpmp4gdepay->streamstateindication > 0) gst_bs_parse_read (&bs, rtpmp4gdepay->streamstateindication); GST_DEBUG_OBJECT (rtpmp4gdepay, "size %d, index %d, delta %d", AU_size, AU_index, AU_index_delta); /* fragmented pakets have the AU_size set to the size of the * unfragmented AU. */ if (AU_size > payload_AU_size) AU_size = payload_AU_size; /* collect stuff in the adapter, strip header from payload and push in * the adapter */ outbuf = gst_rtp_buffer_get_payload_subbuffer (buf, payload_AU, AU_size); gst_adapter_push (rtpmp4gdepay->adapter, outbuf); if (M) { guint avail; /* packet is complete, flush */ avail = gst_adapter_available (rtpmp4gdepay->adapter); outbuf = gst_adapter_take_buffer (rtpmp4gdepay->adapter, avail); gst_buffer_set_caps (outbuf, GST_PAD_CAPS (depayload->srcpad)); /* copy some of the fields we calculated above on the buffer. We also * copy the AU_index so that we can sort the packets in our queue. */ GST_BUFFER_TIMESTAMP (outbuf) = timestamp; GST_BUFFER_OFFSET (outbuf) = AU_index; /* make sure we don't use the timestamp again for other AUs in this * RTP packet. */ timestamp = -1; GST_DEBUG_OBJECT (depayload, "pushing buffer of size %d", GST_BUFFER_SIZE (outbuf)); gst_rtp_mp4g_depay_queue (rtpmp4gdepay, outbuf); } payload_AU += AU_size; payload_AU_size -= AU_size; } } else { /* push complete buffer in adapter */ outbuf = gst_rtp_buffer_get_payload_subbuffer (buf, 0, payload_len); gst_adapter_push (rtpmp4gdepay->adapter, outbuf); /* if this was the last packet of the VOP, create and push a buffer */ if (M) { guint avail; avail = gst_adapter_available (rtpmp4gdepay->adapter); outbuf = gst_adapter_take_buffer (rtpmp4gdepay->adapter, avail); GST_DEBUG ("gst_rtp_mp4g_depay_chain: pushing buffer of size %d", GST_BUFFER_SIZE (outbuf)); return outbuf; } } } return NULL; /* ERRORS */ short_payload: { GST_ELEMENT_WARNING (rtpmp4gdepay, STREAM, DECODE, ("Packet payload was too short."), (NULL)); return NULL; } } static GstStateChangeReturn gst_rtp_mp4g_depay_change_state (GstElement * element, GstStateChange transition) { GstRtpMP4GDepay *rtpmp4gdepay; GstStateChangeReturn ret; rtpmp4gdepay = GST_RTP_MP4G_DEPAY (element); switch (transition) { case GST_STATE_CHANGE_READY_TO_PAUSED: gst_adapter_clear (rtpmp4gdepay->adapter); rtpmp4gdepay->max_AU_index = -1; rtpmp4gdepay->next_AU_index = -1; rtpmp4gdepay->prev_AU_index = -1; rtpmp4gdepay->prev_rtptime = -1; rtpmp4gdepay->last_AU_index = -1; break; default: break; } ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition); switch (transition) { case GST_STATE_CHANGE_PAUSED_TO_READY: gst_adapter_clear (rtpmp4gdepay->adapter); gst_rtp_mp4g_depay_clear_queue (rtpmp4gdepay); break; default: break; } return ret; } gboolean gst_rtp_mp4g_depay_plugin_init (GstPlugin * plugin) { return gst_element_register (plugin, "rtpmp4gdepay", GST_RANK_MARGINAL, GST_TYPE_RTP_MP4G_DEPAY); }