/* GStreamer * Copyright (C) <2006> 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., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include #include #include "gstrtpelements.h" #include "gstrtph264depay.h" #include "gstrtputils.h" GST_DEBUG_CATEGORY_STATIC (rtph264depay_debug); #define GST_CAT_DEFAULT (rtph264depay_debug) /* This is what we'll default to when downstream hasn't * expressed a restriction or preference via caps */ #define DEFAULT_BYTE_STREAM TRUE #define DEFAULT_ACCESS_UNIT FALSE #define DEFAULT_WAIT_FOR_KEYFRAME FALSE #define DEFAULT_REQUEST_KEYFRAME FALSE enum { PROP_0, PROP_WAIT_FOR_KEYFRAME, PROP_REQUEST_KEYFRAME, }; /* 3 zero bytes syncword */ static const guint8 sync_bytes[] = { 0, 0, 0, 1 }; static GstStaticPadTemplate gst_rtp_h264_depay_src_template = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/x-h264, " "stream-format = (string) avc, alignment = (string) au; " "video/x-h264, " "stream-format = (string) byte-stream, alignment = (string) { nal, au }") ); static GstStaticPadTemplate gst_rtp_h264_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) \"H264\"") /* optional parameters */ /* "profile-level-id = (string) ANY, " */ /* "max-mbps = (string) ANY, " */ /* "max-fs = (string) ANY, " */ /* "max-cpb = (string) ANY, " */ /* "max-dpb = (string) ANY, " */ /* "max-br = (string) ANY, " */ /* "redundant-pic-cap = (string) { \"0\", \"1\" }, " */ /* "sprop-parameter-sets = (string) ANY, " */ /* "parameter-add = (string) { \"0\", \"1\" }, " */ /* "packetization-mode = (string) { \"0\", \"1\", \"2\" }, " */ /* "sprop-interleaving-depth = (string) ANY, " */ /* "sprop-deint-buf-req = (string) ANY, " */ /* "deint-buf-cap = (string) ANY, " */ /* "sprop-init-buf-time = (string) ANY, " */ /* "sprop-max-don-diff = (string) ANY, " */ /* "max-rcmd-nalu-size = (string) ANY " */ ); #define gst_rtp_h264_depay_parent_class parent_class G_DEFINE_TYPE_WITH_CODE (GstRtpH264Depay, gst_rtp_h264_depay, GST_TYPE_RTP_BASE_DEPAYLOAD, GST_DEBUG_CATEGORY_INIT (rtph264depay_debug, "rtph264depay", 0, "H264 Video RTP Depayloader")); GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (rtph264depay, "rtph264depay", GST_RANK_SECONDARY, GST_TYPE_RTP_H264_DEPAY, rtp_element_init (plugin)); static void gst_rtp_h264_depay_finalize (GObject * object); static GstStateChangeReturn gst_rtp_h264_depay_change_state (GstElement * element, GstStateChange transition); static GstBuffer *gst_rtp_h264_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp); static gboolean gst_rtp_h264_depay_setcaps (GstRTPBaseDepayload * filter, GstCaps * caps); static gboolean gst_rtp_h264_depay_handle_event (GstRTPBaseDepayload * depay, GstEvent * event); static GstBuffer *gst_rtp_h264_complete_au (GstRtpH264Depay * rtph264depay, GstClockTime * out_timestamp, gboolean * out_keyframe); static void gst_rtp_h264_depay_push (GstRtpH264Depay * rtph264depay, GstBuffer * outbuf, gboolean keyframe, GstClockTime timestamp, gboolean marker); static void gst_rtp_h264_depay_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstRtpH264Depay *self = GST_RTP_H264_DEPAY (object); switch (prop_id) { case PROP_WAIT_FOR_KEYFRAME: self->wait_for_keyframe = g_value_get_boolean (value); break; case PROP_REQUEST_KEYFRAME: self->request_keyframe = g_value_get_boolean (value); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_rtp_h264_depay_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstRtpH264Depay *self = GST_RTP_H264_DEPAY (object); switch (prop_id) { case PROP_WAIT_FOR_KEYFRAME: g_value_set_boolean (value, self->wait_for_keyframe); break; case PROP_REQUEST_KEYFRAME: g_value_set_boolean (value, self->request_keyframe); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_rtp_h264_depay_class_init (GstRtpH264DepayClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; GstRTPBaseDepayloadClass *gstrtpbasedepayload_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass; gobject_class->finalize = gst_rtp_h264_depay_finalize; gobject_class->set_property = gst_rtp_h264_depay_set_property; gobject_class->get_property = gst_rtp_h264_depay_get_property; /** * GstRtpH264Depay:wait-for-keyframe: * * Wait for the next keyframe after packet loss, * meaningful only when outputting access units * * Since: 1.20 */ g_object_class_install_property (gobject_class, PROP_WAIT_FOR_KEYFRAME, g_param_spec_boolean ("wait-for-keyframe", "Wait for Keyframe", "Wait for the next keyframe after packet loss, meaningful only when " "outputting access units", DEFAULT_WAIT_FOR_KEYFRAME, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); /** * GstRtpH264Depay:request-keyframe: * * Request new keyframe when packet loss is detected * * Since: 1.20 */ g_object_class_install_property (gobject_class, PROP_REQUEST_KEYFRAME, g_param_spec_boolean ("request-keyframe", "Request Keyframe", "Request new keyframe when packet loss is detected", DEFAULT_REQUEST_KEYFRAME, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); gst_element_class_add_static_pad_template (gstelement_class, &gst_rtp_h264_depay_src_template); gst_element_class_add_static_pad_template (gstelement_class, &gst_rtp_h264_depay_sink_template); gst_element_class_set_static_metadata (gstelement_class, "RTP H264 depayloader", "Codec/Depayloader/Network/RTP", "Extracts H264 video from RTP packets (RFC 3984)", "Wim Taymans "); gstelement_class->change_state = gst_rtp_h264_depay_change_state; gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_h264_depay_process; gstrtpbasedepayload_class->set_caps = gst_rtp_h264_depay_setcaps; gstrtpbasedepayload_class->handle_event = gst_rtp_h264_depay_handle_event; } static void gst_rtp_h264_depay_init (GstRtpH264Depay * rtph264depay) { rtph264depay->adapter = gst_adapter_new (); rtph264depay->picture_adapter = gst_adapter_new (); rtph264depay->byte_stream = DEFAULT_BYTE_STREAM; rtph264depay->merge = DEFAULT_ACCESS_UNIT; rtph264depay->sps = g_ptr_array_new_with_free_func ( (GDestroyNotify) gst_buffer_unref); rtph264depay->pps = g_ptr_array_new_with_free_func ( (GDestroyNotify) gst_buffer_unref); rtph264depay->wait_for_keyframe = DEFAULT_WAIT_FOR_KEYFRAME; rtph264depay->request_keyframe = DEFAULT_REQUEST_KEYFRAME; } static void gst_rtp_h264_depay_reset (GstRtpH264Depay * rtph264depay, gboolean hard) { gst_adapter_clear (rtph264depay->adapter); rtph264depay->wait_start = TRUE; rtph264depay->waiting_for_keyframe = rtph264depay->wait_for_keyframe; gst_adapter_clear (rtph264depay->picture_adapter); rtph264depay->picture_start = FALSE; rtph264depay->last_keyframe = FALSE; rtph264depay->last_ts = 0; rtph264depay->current_fu_type = 0; rtph264depay->new_codec_data = FALSE; g_ptr_array_set_size (rtph264depay->sps, 0); g_ptr_array_set_size (rtph264depay->pps, 0); if (hard) { if (rtph264depay->allocator != NULL) { gst_object_unref (rtph264depay->allocator); rtph264depay->allocator = NULL; } gst_allocation_params_init (&rtph264depay->params); } } static void gst_rtp_h264_depay_drain (GstRtpH264Depay * rtph264depay) { GstClockTime timestamp; gboolean keyframe; GstBuffer *outbuf; if (!rtph264depay->picture_start) return; outbuf = gst_rtp_h264_complete_au (rtph264depay, ×tamp, &keyframe); if (outbuf) gst_rtp_h264_depay_push (rtph264depay, outbuf, keyframe, timestamp, FALSE); } static void gst_rtp_h264_depay_finalize (GObject * object) { GstRtpH264Depay *rtph264depay; rtph264depay = GST_RTP_H264_DEPAY (object); if (rtph264depay->codec_data) gst_buffer_unref (rtph264depay->codec_data); g_object_unref (rtph264depay->adapter); g_object_unref (rtph264depay->picture_adapter); g_ptr_array_free (rtph264depay->sps, TRUE); g_ptr_array_free (rtph264depay->pps, TRUE); G_OBJECT_CLASS (parent_class)->finalize (object); } static void gst_rtp_h264_depay_negotiate (GstRtpH264Depay * rtph264depay) { GstCaps *caps; gint byte_stream = -1; gint merge = -1; caps = gst_pad_get_allowed_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (rtph264depay)); GST_DEBUG_OBJECT (rtph264depay, "allowed caps: %" GST_PTR_FORMAT, caps); if (caps) { if (gst_caps_get_size (caps) > 0) { GstStructure *s = gst_caps_get_structure (caps, 0); const gchar *str = NULL; if ((str = gst_structure_get_string (s, "stream-format"))) { if (strcmp (str, "avc") == 0) { byte_stream = FALSE; } else if (strcmp (str, "byte-stream") == 0) { byte_stream = TRUE; } else { GST_DEBUG_OBJECT (rtph264depay, "unknown stream-format: %s", str); } } if ((str = gst_structure_get_string (s, "alignment"))) { if (strcmp (str, "au") == 0) { merge = TRUE; } else if (strcmp (str, "nal") == 0) { merge = FALSE; } else { GST_DEBUG_OBJECT (rtph264depay, "unknown alignment: %s", str); } } } gst_caps_unref (caps); } if (byte_stream != -1) { GST_DEBUG_OBJECT (rtph264depay, "downstream requires byte-stream %d", byte_stream); rtph264depay->byte_stream = byte_stream; } else { GST_DEBUG_OBJECT (rtph264depay, "defaulting to byte-stream %d", DEFAULT_BYTE_STREAM); rtph264depay->byte_stream = DEFAULT_BYTE_STREAM; } if (merge != -1) { GST_DEBUG_OBJECT (rtph264depay, "downstream requires merge %d", merge); rtph264depay->merge = merge; } else { GST_DEBUG_OBJECT (rtph264depay, "defaulting to merge %d", DEFAULT_ACCESS_UNIT); rtph264depay->merge = DEFAULT_ACCESS_UNIT; } } static gboolean parse_sps (GstMapInfo * map, guint32 * sps_id) { GstBitReader br = GST_BIT_READER_INIT (map->data + 4, map->size - 4); if (map->size < 5) return FALSE; if (!gst_rtp_read_golomb (&br, sps_id)) return FALSE; return TRUE; } static gboolean parse_pps (GstMapInfo * map, guint32 * sps_id, guint32 * pps_id) { GstBitReader br = GST_BIT_READER_INIT (map->data + 1, map->size - 1); if (map->size < 2) return FALSE; if (!gst_rtp_read_golomb (&br, pps_id)) return FALSE; if (!gst_rtp_read_golomb (&br, sps_id)) return FALSE; return TRUE; } static gboolean gst_rtp_h264_depay_set_output_caps (GstRtpH264Depay * rtph264depay, GstCaps * caps) { GstAllocationParams params; GstAllocator *allocator = NULL; GstPad *srcpad; gboolean res; gst_allocation_params_init (¶ms); srcpad = GST_RTP_BASE_DEPAYLOAD_SRCPAD (rtph264depay); res = gst_pad_set_caps (srcpad, caps); if (res) { GstQuery *query; query = gst_query_new_allocation (caps, TRUE); if (!gst_pad_peer_query (srcpad, query)) { GST_DEBUG_OBJECT (rtph264depay, "downstream ALLOCATION query failed"); } if (gst_query_get_n_allocation_params (query) > 0) { gst_query_parse_nth_allocation_param (query, 0, &allocator, ¶ms); } gst_query_unref (query); } if (rtph264depay->allocator) gst_object_unref (rtph264depay->allocator); rtph264depay->allocator = allocator; rtph264depay->params = params; return res; } static gboolean gst_rtp_h264_set_src_caps (GstRtpH264Depay * rtph264depay) { gboolean res = TRUE; GstCaps *srccaps; GstCaps *old_caps; GstPad *srcpad; if (!rtph264depay->byte_stream && (!rtph264depay->new_codec_data || rtph264depay->sps->len == 0 || rtph264depay->pps->len == 0)) return TRUE; srccaps = gst_caps_new_simple ("video/x-h264", "stream-format", G_TYPE_STRING, rtph264depay->byte_stream ? "byte-stream" : "avc", "alignment", G_TYPE_STRING, rtph264depay->merge ? "au" : "nal", NULL); if (!rtph264depay->byte_stream) { GstBuffer *codec_data; GstMapInfo map; GstMapInfo nalmap; guint8 *data; guint len; guint new_size; guint i, first_sps, num_sps, first_pps, num_pps; guchar level = 0; guchar profile_compat = G_MAXUINT8; /* start with 7 bytes header */ len = 7; /* count sps & pps */ for (i = 0; i < rtph264depay->sps->len; i++) len += 2 + gst_buffer_get_size (g_ptr_array_index (rtph264depay->sps, i)); for (i = 0; i < rtph264depay->pps->len; i++) len += 2 + gst_buffer_get_size (g_ptr_array_index (rtph264depay->pps, i)); codec_data = gst_buffer_new_and_alloc (len); gst_buffer_map (codec_data, &map, GST_MAP_READWRITE); data = map.data; /* 8 bits version == 1 */ *data++ = 1; /* According to: ISO/IEC 14496-15:2004(E) section 5.2.4.1 * The level is the max level of all SPSes * A profile compat bit can only be set if all SPSes include that bit */ for (i = 0; i < rtph264depay->sps->len; i++) { gst_buffer_map (g_ptr_array_index (rtph264depay->sps, i), &nalmap, GST_MAP_READ); profile_compat &= nalmap.data[2]; level = MAX (level, nalmap.data[3]); gst_buffer_unmap (g_ptr_array_index (rtph264depay->sps, i), &nalmap); } /* Assume all SPSes use the same profile, so extract from the first SPS */ gst_buffer_map (g_ptr_array_index (rtph264depay->sps, 0), &nalmap, GST_MAP_READ); *data++ = nalmap.data[1]; gst_buffer_unmap (g_ptr_array_index (rtph264depay->sps, 0), &nalmap); *data++ = profile_compat; *data++ = level; /* 6 bits reserved | 2 bits lengthSizeMinusOn */ *data++ = 0xff; if (rtph264depay->sps->len > 31) { GST_WARNING_OBJECT (rtph264depay, "Too many SPS to put in codec_data. Sending the most recent 31"); num_sps = 31; first_sps = rtph264depay->sps->len - 31; } else { num_sps = rtph264depay->sps->len; first_sps = 0; } /* 3 bits reserved | 5 bits numOfSequenceParameterSets */ *data++ = 0xe0 | (num_sps & 0x1f); /* copy all SPS */ for (i = first_sps; i < rtph264depay->sps->len; i++) { gst_buffer_map (g_ptr_array_index (rtph264depay->sps, i), &nalmap, GST_MAP_READ); GST_DEBUG_OBJECT (rtph264depay, "copy SPS %d of length %u", i, (guint) nalmap.size); GST_WRITE_UINT16_BE (data, nalmap.size); data += 2; memcpy (data, nalmap.data, nalmap.size); data += nalmap.size; gst_buffer_unmap (g_ptr_array_index (rtph264depay->sps, i), &nalmap); } if (rtph264depay->pps->len > 255) { GST_WARNING_OBJECT (rtph264depay, "Too many PPS to put in codec_data. Sending the most recent 255"); num_pps = 255; first_pps = rtph264depay->pps->len - 255; } else { num_pps = rtph264depay->pps->len; first_pps = 0; } /* 8 bits numOfPictureParameterSets */ *data++ = num_pps; /* copy all PPS */ for (i = first_pps; i < rtph264depay->pps->len; i++) { gst_buffer_map (g_ptr_array_index (rtph264depay->pps, i), &nalmap, GST_MAP_READ); GST_DEBUG_OBJECT (rtph264depay, "copy PPS %d of length %u", i, (guint) nalmap.size); GST_WRITE_UINT16_BE (data, nalmap.size); data += 2; memcpy (data, nalmap.data, nalmap.size); data += nalmap.size; gst_buffer_unmap (g_ptr_array_index (rtph264depay->pps, i), &nalmap); } new_size = data - map.data; gst_buffer_unmap (codec_data, &map); gst_buffer_set_size (codec_data, new_size); gst_caps_set_simple (srccaps, "codec_data", GST_TYPE_BUFFER, codec_data, NULL); gst_buffer_unref (codec_data); } /* Set profile a level from SPS */ { gint i; GstBuffer *max_level_sps = NULL; gint level = 0; GstMapInfo nalmap; /* Get the SPS with the highest level. We assume * all SPS have the same profile */ for (i = 0; i < rtph264depay->sps->len; i++) { gst_buffer_map (g_ptr_array_index (rtph264depay->sps, i), &nalmap, GST_MAP_READ); if (level == 0 || level < nalmap.data[3]) { max_level_sps = g_ptr_array_index (rtph264depay->sps, i); level = nalmap.data[3]; } gst_buffer_unmap (g_ptr_array_index (rtph264depay->sps, i), &nalmap); } if (max_level_sps) { gst_buffer_map (max_level_sps, &nalmap, GST_MAP_READ); gst_codec_utils_h264_caps_set_level_and_profile (srccaps, nalmap.data + 1, nalmap.size - 1); gst_buffer_unmap (max_level_sps, &nalmap); } } srcpad = GST_RTP_BASE_DEPAYLOAD_SRCPAD (rtph264depay); old_caps = gst_pad_get_current_caps (srcpad); if (old_caps == NULL || !gst_caps_is_equal (srccaps, old_caps)) { res = gst_rtp_h264_depay_set_output_caps (rtph264depay, srccaps); } gst_clear_caps (&old_caps); gst_caps_unref (srccaps); /* Insert SPS and PPS into the stream on next opportunity (if bytestream) */ if (rtph264depay->byte_stream && (rtph264depay->sps->len > 0 || rtph264depay->pps->len > 0)) { gint i; GstBuffer *codec_data; GstMapInfo map; guint8 *data; guint len = 0; for (i = 0; i < rtph264depay->sps->len; i++) { len += 4 + gst_buffer_get_size (g_ptr_array_index (rtph264depay->sps, i)); } for (i = 0; i < rtph264depay->pps->len; i++) { len += 4 + gst_buffer_get_size (g_ptr_array_index (rtph264depay->pps, i)); } codec_data = gst_buffer_new_and_alloc (len); gst_buffer_map (codec_data, &map, GST_MAP_WRITE); data = map.data; for (i = 0; i < rtph264depay->sps->len; i++) { GstBuffer *sps_buf = g_ptr_array_index (rtph264depay->sps, i); guint sps_size = gst_buffer_get_size (sps_buf); if (rtph264depay->byte_stream) memcpy (data, sync_bytes, sizeof (sync_bytes)); else GST_WRITE_UINT32_BE (data, sps_size); gst_buffer_extract (sps_buf, 0, data + 4, -1); data += 4 + sps_size; } for (i = 0; i < rtph264depay->pps->len; i++) { GstBuffer *pps_buf = g_ptr_array_index (rtph264depay->pps, i); guint pps_size = gst_buffer_get_size (pps_buf); if (rtph264depay->byte_stream) memcpy (data, sync_bytes, sizeof (sync_bytes)); else GST_WRITE_UINT32_BE (data, pps_size); gst_buffer_extract (pps_buf, 0, data + 4, -1); data += 4 + pps_size; } gst_buffer_unmap (codec_data, &map); if (rtph264depay->codec_data) gst_buffer_unref (rtph264depay->codec_data); rtph264depay->codec_data = codec_data; } if (res) rtph264depay->new_codec_data = FALSE; return res; } gboolean gst_rtp_h264_add_sps_pps (GstElement * rtph264, GPtrArray * sps_array, GPtrArray * pps_array, GstBuffer * nal) { GstMapInfo map; guchar type; guint i; gst_buffer_map (nal, &map, GST_MAP_READ); type = map.data[0] & 0x1f; if (type == 7) { guint32 sps_id; if (!parse_sps (&map, &sps_id)) { GST_WARNING_OBJECT (rtph264, "Invalid SPS," " can't parse seq_parameter_set_id"); goto drop; } for (i = 0; i < sps_array->len; i++) { GstBuffer *sps = g_ptr_array_index (sps_array, i); GstMapInfo spsmap; guint32 tmp_sps_id; gst_buffer_map (sps, &spsmap, GST_MAP_READ); parse_sps (&spsmap, &tmp_sps_id); if (sps_id == tmp_sps_id) { /* If this is already the most recent SPS and unchanged, nothing to do */ if (i == (sps_array->len - 1) && map.size == spsmap.size && memcmp (map.data, spsmap.data, spsmap.size) == 0) { GST_LOG_OBJECT (rtph264, "Unchanged SPS %u already most recent, not updating", sps_id); gst_buffer_unmap (sps, &spsmap); goto drop; } else { gst_buffer_unmap (sps, &spsmap); g_ptr_array_remove_index (sps_array, i); g_ptr_array_add (sps_array, nal); GST_LOG_OBJECT (rtph264, "Modified SPS %u, replacing", sps_id); goto done; } } gst_buffer_unmap (sps, &spsmap); } GST_LOG_OBJECT (rtph264, "Adding new SPS %u", sps_id); g_ptr_array_add (sps_array, nal); } else if (type == 8) { guint32 sps_id; guint32 pps_id; if (!parse_pps (&map, &sps_id, &pps_id)) { GST_WARNING_OBJECT (rtph264, "Invalid PPS," " can't parse seq_parameter_set_id or pic_parameter_set_id"); goto drop; } for (i = 0; i < pps_array->len; i++) { GstBuffer *pps = g_ptr_array_index (pps_array, i); GstMapInfo ppsmap; guint32 tmp_sps_id; guint32 tmp_pps_id; gst_buffer_map (pps, &ppsmap, GST_MAP_READ); parse_pps (&ppsmap, &tmp_sps_id, &tmp_pps_id); if (pps_id == tmp_pps_id) { /* If this is already the most recent PPS and unchanged, nothing to do */ if (i == (pps_array->len - 1) && map.size == ppsmap.size && memcmp (map.data, ppsmap.data, ppsmap.size) == 0) { GST_LOG_OBJECT (rtph264, "Unchanged PPS %u:%u already most recent, not updating", sps_id, pps_id); gst_buffer_unmap (pps, &ppsmap); goto drop; } else { gst_buffer_unmap (pps, &ppsmap); g_ptr_array_remove_index (pps_array, i); g_ptr_array_add (pps_array, nal); GST_LOG_OBJECT (rtph264, "Modified PPS %u:%u, replacing", sps_id, pps_id); goto done; } } gst_buffer_unmap (pps, &ppsmap); } GST_LOG_OBJECT (rtph264, "Adding new PPS %u:%i", sps_id, pps_id); g_ptr_array_add (pps_array, nal); } else { goto drop; } done: gst_buffer_unmap (nal, &map); return TRUE; drop: gst_buffer_unmap (nal, &map); gst_buffer_unref (nal); return FALSE; } static void gst_rtp_h264_depay_add_sps_pps (GstRtpH264Depay * rtph264depay, GstBuffer * nal) { if (gst_rtp_h264_add_sps_pps (GST_ELEMENT (rtph264depay), rtph264depay->sps, rtph264depay->pps, nal)) rtph264depay->new_codec_data = TRUE; } static gboolean gst_rtp_h264_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps) { gint clock_rate; GstStructure *structure = gst_caps_get_structure (caps, 0); GstRtpH264Depay *rtph264depay; const gchar *ps; GstBuffer *codec_data; GstMapInfo map; guint8 *ptr; rtph264depay = GST_RTP_H264_DEPAY (depayload); if (!gst_structure_get_int (structure, "clock-rate", &clock_rate)) clock_rate = 90000; depayload->clock_rate = clock_rate; /* Base64 encoded, comma separated config NALs */ ps = gst_structure_get_string (structure, "sprop-parameter-sets"); /* negotiate with downstream w.r.t. output format and alignment */ gst_rtp_h264_depay_negotiate (rtph264depay); if (rtph264depay->byte_stream && ps != NULL) { /* for bytestream we only need the parameter sets but we don't error out * when they are not there, we assume they are in the stream. */ gchar **params; guint len, total; gint i; params = g_strsplit (ps, ",", 0); /* count total number of bytes in base64. Also include the sync bytes in * front of the params. */ len = 0; for (i = 0; params[i]; i++) { len += strlen (params[i]); len += sizeof (sync_bytes); } /* we seriously overshoot the length, but it's fine. */ codec_data = gst_buffer_new_and_alloc (len); gst_buffer_map (codec_data, &map, GST_MAP_WRITE); ptr = map.data; total = 0; for (i = 0; params[i]; i++) { guint save = 0; gint state = 0; GST_DEBUG_OBJECT (depayload, "decoding param %d (%s)", i, params[i]); memcpy (ptr, sync_bytes, sizeof (sync_bytes)); ptr += sizeof (sync_bytes); len = g_base64_decode_step (params[i], strlen (params[i]), ptr, &state, &save); GST_DEBUG_OBJECT (depayload, "decoded %d bytes", len); total += len + sizeof (sync_bytes); ptr += len; } gst_buffer_unmap (codec_data, &map); gst_buffer_resize (codec_data, 0, total); g_strfreev (params); /* keep the codec_data, we need to send it as the first buffer. We cannot * push it in the adapter because the adapter might be flushed on discont. */ if (rtph264depay->codec_data) gst_buffer_unref (rtph264depay->codec_data); rtph264depay->codec_data = codec_data; } else if (!rtph264depay->byte_stream) { gchar **params; gint i; if (ps == NULL) goto incomplete_caps; params = g_strsplit (ps, ",", 0); GST_DEBUG_OBJECT (depayload, "we have %d params", g_strv_length (params)); /* start with 7 bytes header */ for (i = 0; params[i]; i++) { GstBuffer *nal; GstMapInfo nalmap; gsize nal_len; guint save = 0; gint state = 0; nal_len = strlen (params[i]); if (nal_len == 0) { GST_WARNING_OBJECT (depayload, "empty param '%s' (#%d)", params[i], i); continue; } nal = gst_buffer_new_and_alloc (nal_len); gst_buffer_map (nal, &nalmap, GST_MAP_READWRITE); nal_len = g_base64_decode_step (params[i], nal_len, nalmap.data, &state, &save); GST_DEBUG_OBJECT (depayload, "adding param %d as %s", i, ((nalmap.data[0] & 0x1f) == 7) ? "SPS" : "PPS"); gst_buffer_unmap (nal, &nalmap); gst_buffer_set_size (nal, nal_len); gst_rtp_h264_depay_add_sps_pps (rtph264depay, nal); } g_strfreev (params); if (rtph264depay->sps->len == 0 || rtph264depay->pps->len == 0) goto incomplete_caps; } return gst_rtp_h264_set_src_caps (rtph264depay); /* ERRORS */ incomplete_caps: { GST_DEBUG_OBJECT (depayload, "we have incomplete caps," " doing setcaps later"); return TRUE; } } static GstBuffer * gst_rtp_h264_depay_allocate_output_buffer (GstRtpH264Depay * depay, gsize size) { GstBuffer *buffer = NULL; g_return_val_if_fail (size > 0, NULL); GST_LOG_OBJECT (depay, "want output buffer of %u bytes", (guint) size); buffer = gst_buffer_new_allocate (depay->allocator, size, &depay->params); if (buffer == NULL) { GST_INFO_OBJECT (depay, "couldn't allocate output buffer"); buffer = gst_buffer_new_allocate (NULL, size, NULL); } return buffer; } static GstBuffer * gst_rtp_h264_complete_au (GstRtpH264Depay * rtph264depay, GstClockTime * out_timestamp, gboolean * out_keyframe) { GstBufferList *list; GstMapInfo outmap; GstBuffer *outbuf; guint outsize, offset = 0; gint b, n_bufs, m, n_mem; /* we had a picture in the adapter and we completed it */ GST_DEBUG_OBJECT (rtph264depay, "taking completed AU"); outsize = gst_adapter_available (rtph264depay->picture_adapter); outbuf = gst_rtp_h264_depay_allocate_output_buffer (rtph264depay, outsize); if (outbuf == NULL) return NULL; if (!gst_buffer_map (outbuf, &outmap, GST_MAP_WRITE)) return NULL; list = gst_adapter_take_buffer_list (rtph264depay->picture_adapter, outsize); n_bufs = gst_buffer_list_length (list); for (b = 0; b < n_bufs; ++b) { GstBuffer *buf = gst_buffer_list_get (list, b); n_mem = gst_buffer_n_memory (buf); for (m = 0; m < n_mem; ++m) { GstMemory *mem = gst_buffer_peek_memory (buf, m); gsize mem_size = gst_memory_get_sizes (mem, NULL, NULL); GstMapInfo mem_map; if (gst_memory_map (mem, &mem_map, GST_MAP_READ)) { memcpy (outmap.data + offset, mem_map.data, mem_size); gst_memory_unmap (mem, &mem_map); } else { memset (outmap.data + offset, 0, mem_size); } offset += mem_size; } gst_rtp_copy_video_meta (rtph264depay, outbuf, buf); } gst_buffer_list_unref (list); gst_buffer_unmap (outbuf, &outmap); *out_timestamp = rtph264depay->last_ts; *out_keyframe = rtph264depay->last_keyframe; rtph264depay->last_keyframe = FALSE; rtph264depay->picture_start = FALSE; return outbuf; } static void gst_rtp_h264_depay_push (GstRtpH264Depay * rtph264depay, GstBuffer * outbuf, gboolean keyframe, GstClockTime timestamp, gboolean marker) { /* prepend codec_data */ if (rtph264depay->codec_data) { GST_DEBUG_OBJECT (rtph264depay, "prepending codec_data"); gst_rtp_copy_video_meta (rtph264depay, rtph264depay->codec_data, outbuf); outbuf = gst_buffer_append (rtph264depay->codec_data, outbuf); rtph264depay->codec_data = NULL; keyframe = TRUE; } outbuf = gst_buffer_make_writable (outbuf); gst_rtp_drop_non_video_meta (rtph264depay, outbuf); GST_BUFFER_PTS (outbuf) = timestamp; if (keyframe) GST_BUFFER_FLAG_UNSET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT); else GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT); if (marker) GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_MARKER); gst_rtp_base_depayload_push (GST_RTP_BASE_DEPAYLOAD (rtph264depay), outbuf); } /* SPS/PPS/IDR considered key, all others DELTA; * so downstream waiting for keyframe can pick up at SPS/PPS/IDR */ #define NAL_TYPE_IS_KEY(nt) (((nt) == 5) || ((nt) == 7) || ((nt) == 8)) static void gst_rtp_h264_depay_handle_nal (GstRtpH264Depay * rtph264depay, GstBuffer * nal, GstClockTime in_timestamp, gboolean marker) { GstRTPBaseDepayload *depayload = GST_RTP_BASE_DEPAYLOAD (rtph264depay); gint nal_type; GstMapInfo map; GstBuffer *outbuf = NULL; GstClockTime out_timestamp; gboolean keyframe, out_keyframe; gst_buffer_map (nal, &map, GST_MAP_READ); if (G_UNLIKELY (map.size < 5)) goto short_nal; nal_type = map.data[4] & 0x1f; GST_DEBUG_OBJECT (rtph264depay, "handle NAL type %d", nal_type); keyframe = NAL_TYPE_IS_KEY (nal_type); out_keyframe = keyframe; out_timestamp = in_timestamp; if (!rtph264depay->byte_stream) { if (nal_type == 7 || nal_type == 8) { gst_rtp_h264_depay_add_sps_pps (rtph264depay, gst_buffer_copy_region (nal, GST_BUFFER_COPY_ALL, 4, gst_buffer_get_size (nal) - 4)); gst_buffer_unmap (nal, &map); gst_buffer_unref (nal); return; } else if (rtph264depay->sps->len == 0 || rtph264depay->pps->len == 0) { /* Down push down any buffer in non-bytestream mode if the SPS/PPS haven't * go through yet */ gst_pad_push_event (GST_RTP_BASE_DEPAYLOAD_SINKPAD (depayload), gst_event_new_custom (GST_EVENT_CUSTOM_UPSTREAM, gst_structure_new ("GstForceKeyUnit", "all-headers", G_TYPE_BOOLEAN, TRUE, NULL))); gst_buffer_unmap (nal, &map); gst_buffer_unref (nal); return; } if (rtph264depay->new_codec_data && rtph264depay->sps->len > 0 && rtph264depay->pps->len > 0) gst_rtp_h264_set_src_caps (rtph264depay); } if (rtph264depay->merge) { gboolean start = FALSE, complete = FALSE; /* consider a coded slices (IDR or not) to start a picture, * (so ending the previous one) if first_mb_in_slice == 0 * (non-0 is part of previous one) */ /* NOTE this is not entirely according to Access Unit specs in 7.4.1.2.4, * but in practice it works in sane cases, needs not much parsing, * and also works with broken frame_num in NAL (where spec-wise would fail) */ /* FIXME: this code isn't correct for interlaced content as AUs should be * constructed with pairs of fields and the guess here will just push out * AUs with a single field in it */ if (nal_type == 1 || nal_type == 2 || nal_type == 5) { /* we have a picture start */ start = TRUE; if (map.data[5] & 0x80) { /* first_mb_in_slice == 0 completes a picture */ complete = TRUE; } } else if (nal_type >= 6 && nal_type <= 9) { /* SEI, SPS, PPS, AU terminate picture */ complete = TRUE; } GST_DEBUG_OBJECT (depayload, "start %d, complete %d", start, complete); /* marker bit isn't mandatory so in the following code we try to guess * an AU boundary by detecting a new picture start */ if (!marker) { if (complete && rtph264depay->picture_start) outbuf = gst_rtp_h264_complete_au (rtph264depay, &out_timestamp, &out_keyframe); } /* add to adapter */ gst_buffer_unmap (nal, &map); if (!rtph264depay->picture_start && start && out_keyframe) rtph264depay->waiting_for_keyframe = FALSE; GST_DEBUG_OBJECT (depayload, "adding NAL to picture adapter"); gst_adapter_push (rtph264depay->picture_adapter, nal); rtph264depay->last_ts = in_timestamp; rtph264depay->last_keyframe |= keyframe; rtph264depay->picture_start |= start; if (marker) outbuf = gst_rtp_h264_complete_au (rtph264depay, &out_timestamp, &out_keyframe); } else { /* no merge, output is input nal */ GST_DEBUG_OBJECT (depayload, "using NAL as output"); outbuf = nal; gst_buffer_unmap (nal, &map); } if (outbuf) { if (!rtph264depay->waiting_for_keyframe) { gst_rtp_h264_depay_push (rtph264depay, outbuf, out_keyframe, out_timestamp, marker); } else { GST_LOG_OBJECT (depayload, "Dropping %" GST_PTR_FORMAT ", we are waiting for a keyframe", outbuf); gst_buffer_unref (outbuf); } } return; /* ERRORS */ short_nal: { GST_WARNING_OBJECT (depayload, "dropping short NAL"); gst_buffer_unmap (nal, &map); gst_buffer_unref (nal); return; } } static void gst_rtp_h264_finish_fragmentation_unit (GstRtpH264Depay * rtph264depay) { guint outsize; GstMapInfo map; GstBuffer *outbuf; outsize = gst_adapter_available (rtph264depay->adapter); outbuf = gst_adapter_take_buffer (rtph264depay->adapter, outsize); gst_buffer_map (outbuf, &map, GST_MAP_WRITE); GST_DEBUG_OBJECT (rtph264depay, "output %d bytes", outsize); if (rtph264depay->byte_stream) { memcpy (map.data, sync_bytes, sizeof (sync_bytes)); } else { outsize -= 4; map.data[0] = (outsize >> 24); map.data[1] = (outsize >> 16); map.data[2] = (outsize >> 8); map.data[3] = (outsize); } gst_buffer_unmap (outbuf, &map); rtph264depay->current_fu_type = 0; gst_rtp_h264_depay_handle_nal (rtph264depay, outbuf, rtph264depay->fu_timestamp, rtph264depay->fu_marker); } static GstBuffer * gst_rtp_h264_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp) { GstRtpH264Depay *rtph264depay; GstBuffer *outbuf = NULL; guint8 nal_unit_type; rtph264depay = GST_RTP_H264_DEPAY (depayload); if (!rtph264depay->merge) rtph264depay->waiting_for_keyframe = FALSE; /* flush remaining data on discont */ if (GST_BUFFER_IS_DISCONT (rtp->buffer)) { gst_adapter_clear (rtph264depay->adapter); rtph264depay->wait_start = TRUE; rtph264depay->current_fu_type = 0; rtph264depay->last_fu_seqnum = 0; if (rtph264depay->merge && rtph264depay->wait_for_keyframe) { rtph264depay->waiting_for_keyframe = TRUE; } if (rtph264depay->request_keyframe) gst_pad_push_event (GST_RTP_BASE_DEPAYLOAD_SINKPAD (depayload), gst_video_event_new_upstream_force_key_unit (GST_CLOCK_TIME_NONE, TRUE, 0)); } { gint payload_len; guint8 *payload; guint header_len; guint8 nal_ref_idc; GstMapInfo map; guint outsize, nalu_size; GstClockTime timestamp; gboolean marker; timestamp = GST_BUFFER_PTS (rtp->buffer); payload_len = gst_rtp_buffer_get_payload_len (rtp); payload = gst_rtp_buffer_get_payload (rtp); marker = gst_rtp_buffer_get_marker (rtp); GST_DEBUG_OBJECT (rtph264depay, "receiving %d bytes", payload_len); if (payload_len == 0) goto empty_packet; /* +---------------+ * |0|1|2|3|4|5|6|7| * +-+-+-+-+-+-+-+-+ * |F|NRI| Type | * +---------------+ * * F must be 0. */ nal_ref_idc = (payload[0] & 0x60) >> 5; nal_unit_type = payload[0] & 0x1f; /* at least one byte header with type */ header_len = 1; GST_DEBUG_OBJECT (rtph264depay, "NRI %d, Type %d %s", nal_ref_idc, nal_unit_type, marker ? "marker" : ""); /* If FU unit was being processed, but the current nal is of a different * type. Assume that the remote payloader is buggy (didn't set the end bit * when the FU ended) and send out what we gathered thusfar */ if (G_UNLIKELY (rtph264depay->current_fu_type != 0 && nal_unit_type != rtph264depay->current_fu_type)) gst_rtp_h264_finish_fragmentation_unit (rtph264depay); switch (nal_unit_type) { case 0: case 30: case 31: /* undefined */ goto undefined_type; case 25: /* STAP-B Single-time aggregation packet 5.7.1 */ /* 2 byte extra header for DON */ header_len += 2; /* fallthrough */ case 24: { /* strip headers */ payload += header_len; payload_len -= header_len; rtph264depay->wait_start = FALSE; /* STAP-A Single-time aggregation packet 5.7.1 */ while (payload_len > 2) { gboolean last = FALSE; /* 1 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | NALU Size | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ nalu_size = (payload[0] << 8) | payload[1]; /* don't include nalu_size */ if (nalu_size > (payload_len - 2)) nalu_size = payload_len - 2; outsize = nalu_size + sizeof (sync_bytes); outbuf = gst_buffer_new_and_alloc (outsize); gst_buffer_map (outbuf, &map, GST_MAP_WRITE); if (rtph264depay->byte_stream) { memcpy (map.data, sync_bytes, sizeof (sync_bytes)); } else { map.data[0] = map.data[1] = 0; map.data[2] = payload[0]; map.data[3] = payload[1]; } /* strip NALU size */ payload += 2; payload_len -= 2; memcpy (map.data + sizeof (sync_bytes), payload, nalu_size); gst_buffer_unmap (outbuf, &map); gst_rtp_copy_video_meta (rtph264depay, outbuf, rtp->buffer); if (payload_len - nalu_size <= 2) last = TRUE; gst_rtp_h264_depay_handle_nal (rtph264depay, outbuf, timestamp, marker && last); payload += nalu_size; payload_len -= nalu_size; } break; } case 26: /* MTAP16 Multi-time aggregation packet 5.7.2 */ // header_len = 5; /* fallthrough, not implemented */ case 27: /* MTAP24 Multi-time aggregation packet 5.7.2 */ // header_len = 6; goto not_implemented; break; case 28: case 29: { /* FU-A Fragmentation unit 5.8 */ /* FU-B Fragmentation unit 5.8 */ gboolean S, E; /* +---------------+ * |0|1|2|3|4|5|6|7| * +-+-+-+-+-+-+-+-+ * |S|E|R| Type | * +---------------+ * * R is reserved and always 0 */ S = (payload[1] & 0x80) == 0x80; E = (payload[1] & 0x40) == 0x40; GST_DEBUG_OBJECT (rtph264depay, "S %d, E %d", S, E); if (rtph264depay->wait_start && !S) goto waiting_start; if (S) { /* NAL unit starts here */ guint8 nal_header; /* If a new FU unit started, while still processing an older one. * Assume that the remote payloader is buggy (doesn't set the end * bit) and send out what we've gathered thusfar */ if (G_UNLIKELY (rtph264depay->current_fu_type != 0)) gst_rtp_h264_finish_fragmentation_unit (rtph264depay); rtph264depay->current_fu_type = nal_unit_type; rtph264depay->fu_timestamp = timestamp; rtph264depay->last_fu_seqnum = gst_rtp_buffer_get_seq (rtp); rtph264depay->wait_start = FALSE; /* reconstruct NAL header */ nal_header = (payload[0] & 0xe0) | (payload[1] & 0x1f); /* strip type header, keep FU header, we'll reuse it to reconstruct * the NAL header. */ payload += 1; payload_len -= 1; nalu_size = payload_len; outsize = nalu_size + sizeof (sync_bytes); outbuf = gst_buffer_new_and_alloc (outsize); gst_buffer_map (outbuf, &map, GST_MAP_WRITE); memcpy (map.data + sizeof (sync_bytes), payload, nalu_size); map.data[sizeof (sync_bytes)] = nal_header; gst_buffer_unmap (outbuf, &map); gst_rtp_copy_video_meta (rtph264depay, outbuf, rtp->buffer); GST_DEBUG_OBJECT (rtph264depay, "queueing %d bytes", outsize); /* and assemble in the adapter */ gst_adapter_push (rtph264depay->adapter, outbuf); } else { if (rtph264depay->current_fu_type == 0) { /* previous FU packet missing start bit? */ GST_WARNING_OBJECT (rtph264depay, "missing FU start bit on an " "earlier packet. Dropping."); gst_adapter_clear (rtph264depay->adapter); return NULL; } if (gst_rtp_buffer_compare_seqnum (rtph264depay->last_fu_seqnum, gst_rtp_buffer_get_seq (rtp)) != 1) { /* jump in sequence numbers within an FU is cause for discarding */ GST_WARNING_OBJECT (rtph264depay, "Jump in sequence numbers from " "%u to %u within Fragmentation Unit. Data was lost, dropping " "stored.", rtph264depay->last_fu_seqnum, gst_rtp_buffer_get_seq (rtp)); gst_adapter_clear (rtph264depay->adapter); return NULL; } rtph264depay->last_fu_seqnum = gst_rtp_buffer_get_seq (rtp); /* strip off FU indicator and FU header bytes */ payload += 2; payload_len -= 2; outsize = payload_len; outbuf = gst_buffer_new_and_alloc (outsize); gst_buffer_fill (outbuf, 0, payload, outsize); gst_rtp_copy_video_meta (rtph264depay, outbuf, rtp->buffer); GST_DEBUG_OBJECT (rtph264depay, "queueing %d bytes", outsize); /* and assemble in the adapter */ gst_adapter_push (rtph264depay->adapter, outbuf); } outbuf = NULL; rtph264depay->fu_marker = marker; /* if NAL unit ends, flush the adapter */ if (E) gst_rtp_h264_finish_fragmentation_unit (rtph264depay); break; } default: { rtph264depay->wait_start = FALSE; /* 1-23 NAL unit Single NAL unit packet per H.264 5.6 */ /* the entire payload is the output buffer */ nalu_size = payload_len; outsize = nalu_size + sizeof (sync_bytes); outbuf = gst_buffer_new_and_alloc (outsize); gst_buffer_map (outbuf, &map, GST_MAP_WRITE); if (rtph264depay->byte_stream) { memcpy (map.data, sync_bytes, sizeof (sync_bytes)); } else { map.data[0] = map.data[1] = 0; map.data[2] = nalu_size >> 8; map.data[3] = nalu_size & 0xff; } memcpy (map.data + sizeof (sync_bytes), payload, nalu_size); gst_buffer_unmap (outbuf, &map); gst_rtp_copy_video_meta (rtph264depay, outbuf, rtp->buffer); gst_rtp_h264_depay_handle_nal (rtph264depay, outbuf, timestamp, marker); break; } } } return NULL; /* ERRORS */ empty_packet: { GST_DEBUG_OBJECT (rtph264depay, "empty packet"); return NULL; } undefined_type: { GST_ELEMENT_WARNING (rtph264depay, STREAM, DECODE, (NULL), ("Undefined packet type")); return NULL; } waiting_start: { GST_DEBUG_OBJECT (rtph264depay, "waiting for start"); return NULL; } not_implemented: { GST_ELEMENT_ERROR (rtph264depay, STREAM, FORMAT, (NULL), ("NAL unit type %d not supported yet", nal_unit_type)); return NULL; } } static gboolean gst_rtp_h264_depay_handle_event (GstRTPBaseDepayload * depay, GstEvent * event) { GstRtpH264Depay *rtph264depay; rtph264depay = GST_RTP_H264_DEPAY (depay); switch (GST_EVENT_TYPE (event)) { case GST_EVENT_FLUSH_STOP: gst_rtp_h264_depay_reset (rtph264depay, FALSE); break; case GST_EVENT_EOS: gst_rtp_h264_depay_drain (rtph264depay); break; default: break; } return GST_RTP_BASE_DEPAYLOAD_CLASS (parent_class)->handle_event (depay, event); } static GstStateChangeReturn gst_rtp_h264_depay_change_state (GstElement * element, GstStateChange transition) { GstRtpH264Depay *rtph264depay; GstStateChangeReturn ret; rtph264depay = GST_RTP_H264_DEPAY (element); switch (transition) { case GST_STATE_CHANGE_NULL_TO_READY: break; case GST_STATE_CHANGE_READY_TO_PAUSED: gst_rtp_h264_depay_reset (rtph264depay, TRUE); break; default: break; } ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition); switch (transition) { case GST_STATE_CHANGE_PAUSED_TO_READY: gst_rtp_h264_depay_reset (rtph264depay, TRUE); break; case GST_STATE_CHANGE_READY_TO_NULL: break; default: break; } return ret; }