| /* |
| * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| // This file contains structures for describing SSRCs from a media source such |
| // as a MediaStreamTrack when it is sent across an RTP session. Multiple media |
| // sources may be sent across the same RTP session, each of them will be |
| // described by one StreamParams object |
| // SsrcGroup is used to describe the relationship between the SSRCs that |
| // are used for this media source. |
| // E.x: Consider a source that is sent as 3 simulcast streams |
| // Let the simulcast elements have SSRC 10, 20, 30. |
| // Let each simulcast element use FEC and let the protection packets have |
| // SSRC 11,21,31. |
| // To describe this 4 SsrcGroups are needed, |
| // StreamParams would then contain ssrc = {10,11,20,21,30,31} and |
| // ssrc_groups = {{SIM,{10,20,30}, {FEC,{10,11}, {FEC, {20,21}, {FEC {30,31}}} |
| // Please see RFC 5576. |
| // A spec-compliant way to achieve this is to use RIDs and Simulcast attribute |
| // instead of the ssrc-group. In this method, the StreamParam object will |
| // have multiple RidDescriptions, each corresponding to a simulcast layer |
| // and the media section will have a simulcast attribute that indicates |
| // that these layers are for the same source. This also removes the extra |
| // lines for redundancy streams, as the same RIDs appear in the redundancy |
| // packets. |
| // Note: in the spec compliant simulcast scenario, some of the RIDs might be |
| // alternatives for one another (such as different encodings for same data). |
| // In the context of the StreamParams class, the notion of alternatives does |
| // not exist and all the RIDs will describe different layers of the same source. |
| // When the StreamParams class is used to configure the media engine, simulcast |
| // considerations will be used to remove the alternative layers outside of this |
| // class. |
| // As an example, let the simulcast layers have RID 10, 20, 30. |
| // StreamParams would contain rid = { 10, 20, 30 }. |
| // MediaSection would contain SimulcastDescription specifying these rids. |
| // a=simulcast:send 10;20;30 (or a=simulcast:send 10,20;30 or similar). |
| // See https://tools.ietf.org/html/draft-ietf-mmusic-sdp-simulcast-13 |
| // and https://tools.ietf.org/html/draft-ietf-mmusic-rid-15. |
| |
| #ifndef MEDIA_BASE_STREAMPARAMS_H_ |
| #define MEDIA_BASE_STREAMPARAMS_H_ |
| |
| #include <stddef.h> |
| #include <algorithm> |
| #include <cstdint> |
| #include <string> |
| #include <vector> |
| |
| #include "media/base/riddescription.h" |
| #include "rtc_base/constructormagic.h" |
| |
| namespace cricket { |
| |
| extern const char kFecSsrcGroupSemantics[]; |
| extern const char kFecFrSsrcGroupSemantics[]; |
| extern const char kFidSsrcGroupSemantics[]; |
| extern const char kSimSsrcGroupSemantics[]; |
| |
| struct SsrcGroup { |
| SsrcGroup(const std::string& usage, const std::vector<uint32_t>& ssrcs); |
| SsrcGroup(const SsrcGroup&); |
| SsrcGroup(SsrcGroup&&); |
| ~SsrcGroup(); |
| SsrcGroup& operator=(const SsrcGroup&); |
| SsrcGroup& operator=(SsrcGroup&&); |
| |
| bool operator==(const SsrcGroup& other) const { |
| return (semantics == other.semantics && ssrcs == other.ssrcs); |
| } |
| bool operator!=(const SsrcGroup& other) const { return !(*this == other); } |
| |
| bool has_semantics(const std::string& semantics) const; |
| |
| std::string ToString() const; |
| |
| std::string semantics; // e.g FIX, FEC, SIM. |
| std::vector<uint32_t> ssrcs; // SSRCs of this type. |
| }; |
| |
| // StreamParams is used to represent a sender/track in a SessionDescription. |
| // In Plan B, this means that multiple StreamParams can exist within one |
| // MediaContentDescription, while in UnifiedPlan this means that there is one |
| // StreamParams per MediaContentDescription. |
| struct StreamParams { |
| StreamParams(); |
| StreamParams(const StreamParams&); |
| StreamParams(StreamParams&&); |
| ~StreamParams(); |
| StreamParams& operator=(const StreamParams&); |
| StreamParams& operator=(StreamParams&&); |
| |
| static StreamParams CreateLegacy(uint32_t ssrc) { |
| StreamParams stream; |
| stream.ssrcs.push_back(ssrc); |
| return stream; |
| } |
| |
| bool operator==(const StreamParams& other) const; |
| bool operator!=(const StreamParams& other) const { return !(*this == other); } |
| |
| uint32_t first_ssrc() const { |
| if (ssrcs.empty()) { |
| return 0; |
| } |
| |
| return ssrcs[0]; |
| } |
| bool has_ssrcs() const { return !ssrcs.empty(); } |
| bool has_ssrc(uint32_t ssrc) const { |
| return std::find(ssrcs.begin(), ssrcs.end(), ssrc) != ssrcs.end(); |
| } |
| void add_ssrc(uint32_t ssrc) { ssrcs.push_back(ssrc); } |
| bool has_ssrc_groups() const { return !ssrc_groups.empty(); } |
| bool has_ssrc_group(const std::string& semantics) const { |
| return (get_ssrc_group(semantics) != NULL); |
| } |
| const SsrcGroup* get_ssrc_group(const std::string& semantics) const { |
| for (std::vector<SsrcGroup>::const_iterator it = ssrc_groups.begin(); |
| it != ssrc_groups.end(); ++it) { |
| if (it->has_semantics(semantics)) { |
| return &(*it); |
| } |
| } |
| return NULL; |
| } |
| |
| // Convenience function to add an FID ssrc for a primary_ssrc |
| // that's already been added. |
| bool AddFidSsrc(uint32_t primary_ssrc, uint32_t fid_ssrc) { |
| return AddSecondarySsrc(kFidSsrcGroupSemantics, primary_ssrc, fid_ssrc); |
| } |
| |
| // Convenience function to lookup the FID ssrc for a primary_ssrc. |
| // Returns false if primary_ssrc not found or FID not defined for it. |
| bool GetFidSsrc(uint32_t primary_ssrc, uint32_t* fid_ssrc) const { |
| return GetSecondarySsrc(kFidSsrcGroupSemantics, primary_ssrc, fid_ssrc); |
| } |
| |
| // Convenience function to add an FEC-FR ssrc for a primary_ssrc |
| // that's already been added. |
| bool AddFecFrSsrc(uint32_t primary_ssrc, uint32_t fecfr_ssrc) { |
| return AddSecondarySsrc(kFecFrSsrcGroupSemantics, primary_ssrc, fecfr_ssrc); |
| } |
| |
| // Convenience function to lookup the FEC-FR ssrc for a primary_ssrc. |
| // Returns false if primary_ssrc not found or FEC-FR not defined for it. |
| bool GetFecFrSsrc(uint32_t primary_ssrc, uint32_t* fecfr_ssrc) const { |
| return GetSecondarySsrc(kFecFrSsrcGroupSemantics, primary_ssrc, fecfr_ssrc); |
| } |
| |
| // Convenience to get all the SIM SSRCs if there are SIM ssrcs, or |
| // the first SSRC otherwise. |
| void GetPrimarySsrcs(std::vector<uint32_t>* ssrcs) const; |
| |
| // Convenience to get all the FID SSRCs for the given primary ssrcs. |
| // If a given primary SSRC does not have a FID SSRC, the list of FID |
| // SSRCS will be smaller than the list of primary SSRCs. |
| void GetFidSsrcs(const std::vector<uint32_t>& primary_ssrcs, |
| std::vector<uint32_t>* fid_ssrcs) const; |
| |
| // Stream ids serialized to SDP. |
| std::vector<std::string> stream_ids() const; |
| void set_stream_ids(const std::vector<std::string>& stream_ids); |
| |
| // Returns the first stream id or "" if none exist. This method exists only |
| // as temporary backwards compatibility with the old sync_label. |
| std::string first_stream_id() const; |
| |
| std::string ToString() const; |
| |
| // Resource of the MUC jid of the participant of with this stream. |
| // For 1:1 calls, should be left empty (which means remote streams |
| // and local streams should not be mixed together). This is not used |
| // internally and should be deprecated. |
| std::string groupid; |
| // A unique identifier of the StreamParams object. When the SDP is created, |
| // this comes from the track ID of the sender that the StreamParams object |
| // is associated with. |
| std::string id; |
| // There may be no SSRCs stored in unsignaled case when stream_ids are |
| // signaled with a=msid lines. |
| std::vector<uint32_t> ssrcs; // All SSRCs for this source |
| std::vector<SsrcGroup> ssrc_groups; // e.g. FID, FEC, SIM |
| std::string cname; // RTCP CNAME |
| |
| // RID functionality according to |
| // https://tools.ietf.org/html/draft-ietf-mmusic-rid-15 |
| // Each layer can be represented by a RID identifier and can also have |
| // restrictions (such as max-width, max-height, etc.) |
| // If the track has multiple layers (ex. Simulcast), each layer will be |
| // represented by a RID. |
| bool has_rids() const { return !rids_.empty(); } |
| const std::vector<RidDescription>& rids() const { return rids_; } |
| void set_rids(const std::vector<RidDescription>& rids) { rids_ = rids; } |
| |
| private: |
| bool AddSecondarySsrc(const std::string& semantics, |
| uint32_t primary_ssrc, |
| uint32_t secondary_ssrc); |
| bool GetSecondarySsrc(const std::string& semantics, |
| uint32_t primary_ssrc, |
| uint32_t* secondary_ssrc) const; |
| |
| // The stream IDs of the sender that the StreamParams object is associated |
| // with. In Plan B this should always be size of 1, while in Unified Plan this |
| // could be none or multiple stream IDs. |
| std::vector<std::string> stream_ids_; |
| |
| std::vector<RidDescription> rids_; |
| }; |
| |
| // A Stream can be selected by either groupid+id or ssrc. |
| struct StreamSelector { |
| explicit StreamSelector(uint32_t ssrc) : ssrc(ssrc) {} |
| |
| StreamSelector(const std::string& groupid, const std::string& streamid) |
| : ssrc(0), groupid(groupid), streamid(streamid) {} |
| |
| explicit StreamSelector(const std::string& streamid) |
| : ssrc(0), streamid(streamid) {} |
| |
| bool Matches(const StreamParams& stream) const { |
| if (ssrc == 0) { |
| return stream.groupid == groupid && stream.id == streamid; |
| } else { |
| return stream.has_ssrc(ssrc); |
| } |
| } |
| |
| uint32_t ssrc; |
| std::string groupid; |
| std::string streamid; |
| }; |
| |
| typedef std::vector<StreamParams> StreamParamsVec; |
| |
| // A collection of audio and video and data streams. Most of the |
| // methods are merely for convenience. Many of these methods are keyed |
| // by ssrc, which is the source identifier in the RTP spec |
| // (http://tools.ietf.org/html/rfc3550). |
| // TODO(pthatcher): Add basic unit test for these. |
| // See https://code.google.com/p/webrtc/issues/detail?id=4107 |
| struct MediaStreams { |
| public: |
| MediaStreams(); |
| ~MediaStreams(); |
| void CopyFrom(const MediaStreams& sources); |
| |
| bool empty() const { |
| return audio_.empty() && video_.empty() && data_.empty(); |
| } |
| |
| std::vector<StreamParams>* mutable_audio() { return &audio_; } |
| std::vector<StreamParams>* mutable_video() { return &video_; } |
| std::vector<StreamParams>* mutable_data() { return &data_; } |
| const std::vector<StreamParams>& audio() const { return audio_; } |
| const std::vector<StreamParams>& video() const { return video_; } |
| const std::vector<StreamParams>& data() const { return data_; } |
| |
| // Gets a stream, returning true if found. |
| bool GetAudioStream(const StreamSelector& selector, StreamParams* stream); |
| bool GetVideoStream(const StreamSelector& selector, StreamParams* stream); |
| bool GetDataStream(const StreamSelector& selector, StreamParams* stream); |
| // Adds a stream. |
| void AddAudioStream(const StreamParams& stream); |
| void AddVideoStream(const StreamParams& stream); |
| void AddDataStream(const StreamParams& stream); |
| // Removes a stream, returning true if found and removed. |
| bool RemoveAudioStream(const StreamSelector& selector); |
| bool RemoveVideoStream(const StreamSelector& selector); |
| bool RemoveDataStream(const StreamSelector& selector); |
| |
| private: |
| std::vector<StreamParams> audio_; |
| std::vector<StreamParams> video_; |
| std::vector<StreamParams> data_; |
| |
| RTC_DISALLOW_COPY_AND_ASSIGN(MediaStreams); |
| }; |
| |
| template <class Condition> |
| const StreamParams* GetStream(const StreamParamsVec& streams, |
| Condition condition) { |
| StreamParamsVec::const_iterator found = |
| std::find_if(streams.begin(), streams.end(), condition); |
| return found == streams.end() ? nullptr : &(*found); |
| } |
| |
| template <class Condition> |
| StreamParams* GetStream(StreamParamsVec& streams, Condition condition) { |
| StreamParamsVec::iterator found = |
| std::find_if(streams.begin(), streams.end(), condition); |
| return found == streams.end() ? nullptr : &(*found); |
| } |
| |
| inline bool HasStreamWithNoSsrcs(const StreamParamsVec& streams) { |
| return GetStream(streams, |
| [](const StreamParams& sp) { return !sp.has_ssrcs(); }); |
| } |
| |
| inline const StreamParams* GetStreamBySsrc(const StreamParamsVec& streams, |
| uint32_t ssrc) { |
| return GetStream( |
| streams, [&ssrc](const StreamParams& sp) { return sp.has_ssrc(ssrc); }); |
| } |
| |
| inline const StreamParams* GetStreamByIds(const StreamParamsVec& streams, |
| const std::string& groupid, |
| const std::string& id) { |
| return GetStream(streams, [&groupid, &id](const StreamParams& sp) { |
| return sp.groupid == groupid && sp.id == id; |
| }); |
| } |
| |
| inline StreamParams* GetStreamByIds(StreamParamsVec& streams, |
| const std::string& groupid, |
| const std::string& id) { |
| return GetStream(streams, [&groupid, &id](const StreamParams& sp) { |
| return sp.groupid == groupid && sp.id == id; |
| }); |
| } |
| |
| inline const StreamParams* GetStream(const StreamParamsVec& streams, |
| const StreamSelector& selector) { |
| return GetStream(streams, [&selector](const StreamParams& sp) { |
| return selector.Matches(sp); |
| }); |
| } |
| |
| template <class Condition> |
| bool RemoveStream(StreamParamsVec* streams, Condition condition) { |
| auto iter(std::remove_if(streams->begin(), streams->end(), condition)); |
| if (iter == streams->end()) |
| return false; |
| streams->erase(iter, streams->end()); |
| return true; |
| } |
| |
| // Removes the stream from streams. Returns true if a stream is |
| // found and removed. |
| inline bool RemoveStream(StreamParamsVec* streams, |
| const StreamSelector& selector) { |
| return RemoveStream(streams, [&selector](const StreamParams& sp) { |
| return selector.Matches(sp); |
| }); |
| } |
| inline bool RemoveStreamBySsrc(StreamParamsVec* streams, uint32_t ssrc) { |
| return RemoveStream( |
| streams, [&ssrc](const StreamParams& sp) { return sp.has_ssrc(ssrc); }); |
| } |
| inline bool RemoveStreamByIds(StreamParamsVec* streams, |
| const std::string& groupid, |
| const std::string& id) { |
| return RemoveStream(streams, [&groupid, &id](const StreamParams& sp) { |
| return sp.groupid == groupid && sp.id == id; |
| }); |
| } |
| |
| // Checks if |sp| defines parameters for a single primary stream. There may |
| // be an RTX stream or a FlexFEC stream (or both) associated with the primary |
| // stream. Leaving as non-static so we can test this function. |
| bool IsOneSsrcStream(const StreamParams& sp); |
| |
| // Checks if |sp| defines parameters for one Simulcast stream. There may be RTX |
| // streams associated with the simulcast streams. Leaving as non-static so we |
| // can test this function. |
| bool IsSimulcastStream(const StreamParams& sp); |
| |
| } // namespace cricket |
| |
| #endif // MEDIA_BASE_STREAMPARAMS_H_ |