1 /*
2 * libjingle
3 * Copyright 2011 Google Inc.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice,
9 * this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 // This file contains structures for describing SSRCs from a media source such
29 // as a MediaStreamTrack when it is sent across an RTP session. Multiple media
30 // sources may be sent across the same RTP session, each of them will be
31 // described by one StreamParams object
32 // SsrcGroup is used to describe the relationship between the SSRCs that
33 // are used for this media source.
34 // E.x: Consider a source that is sent as 3 simulcast streams
35 // Let the simulcast elements have SSRC 10, 20, 30.
36 // Let each simulcast element use FEC and let the protection packets have
37 // SSRC 11,21,31.
38 // To describe this 4 SsrcGroups are needed,
39 // StreamParams would then contain ssrc = {10,11,20,21,30,31} and
40 // ssrc_groups = {{SIM,{10,20,30}, {FEC,{10,11}, {FEC, {20,21}, {FEC {30,31}}}
41 // Please see RFC 5576.
42
43 #ifndef TALK_MEDIA_BASE_STREAMPARAMS_H_
44 #define TALK_MEDIA_BASE_STREAMPARAMS_H_
45
46 #include <algorithm>
47 #include <set>
48 #include <string>
49 #include <vector>
50
51 #include "webrtc/base/basictypes.h"
52 #include "webrtc/base/constructormagic.h"
53
54 namespace cricket {
55
56 extern const char kFecSsrcGroupSemantics[];
57 extern const char kFidSsrcGroupSemantics[];
58 extern const char kSimSsrcGroupSemantics[];
59
60 struct SsrcGroup {
SsrcGroupSsrcGroup61 SsrcGroup(const std::string& usage, const std::vector<uint32_t>& ssrcs)
62 : semantics(usage), ssrcs(ssrcs) {}
63
64 bool operator==(const SsrcGroup& other) const {
65 return (semantics == other.semantics && ssrcs == other.ssrcs);
66 }
67 bool operator!=(const SsrcGroup &other) const {
68 return !(*this == other);
69 }
70
71 bool has_semantics(const std::string& semantics) const;
72
73 std::string ToString() const;
74
75 std::string semantics; // e.g FIX, FEC, SIM.
76 std::vector<uint32_t> ssrcs; // SSRCs of this type.
77 };
78
79 struct StreamParams {
CreateLegacyStreamParams80 static StreamParams CreateLegacy(uint32_t ssrc) {
81 StreamParams stream;
82 stream.ssrcs.push_back(ssrc);
83 return stream;
84 }
85
86 bool operator==(const StreamParams& other) const {
87 return (groupid == other.groupid &&
88 id == other.id &&
89 ssrcs == other.ssrcs &&
90 ssrc_groups == other.ssrc_groups &&
91 type == other.type &&
92 display == other.display &&
93 cname == other.cname &&
94 sync_label == other.sync_label);
95 }
96 bool operator!=(const StreamParams &other) const {
97 return !(*this == other);
98 }
99
first_ssrcStreamParams100 uint32_t first_ssrc() const {
101 if (ssrcs.empty()) {
102 return 0;
103 }
104
105 return ssrcs[0];
106 }
has_ssrcsStreamParams107 bool has_ssrcs() const {
108 return !ssrcs.empty();
109 }
has_ssrcStreamParams110 bool has_ssrc(uint32_t ssrc) const {
111 return std::find(ssrcs.begin(), ssrcs.end(), ssrc) != ssrcs.end();
112 }
add_ssrcStreamParams113 void add_ssrc(uint32_t ssrc) { ssrcs.push_back(ssrc); }
has_ssrc_groupsStreamParams114 bool has_ssrc_groups() const {
115 return !ssrc_groups.empty();
116 }
has_ssrc_groupStreamParams117 bool has_ssrc_group(const std::string& semantics) const {
118 return (get_ssrc_group(semantics) != NULL);
119 }
get_ssrc_groupStreamParams120 const SsrcGroup* get_ssrc_group(const std::string& semantics) const {
121 for (std::vector<SsrcGroup>::const_iterator it = ssrc_groups.begin();
122 it != ssrc_groups.end(); ++it) {
123 if (it->has_semantics(semantics)) {
124 return &(*it);
125 }
126 }
127 return NULL;
128 }
129
130 // Convenience function to add an FID ssrc for a primary_ssrc
131 // that's already been added.
AddFidSsrcStreamParams132 inline bool AddFidSsrc(uint32_t primary_ssrc, uint32_t fid_ssrc) {
133 return AddSecondarySsrc(kFidSsrcGroupSemantics, primary_ssrc, fid_ssrc);
134 }
135
136 // Convenience function to lookup the FID ssrc for a primary_ssrc.
137 // Returns false if primary_ssrc not found or FID not defined for it.
GetFidSsrcStreamParams138 inline bool GetFidSsrc(uint32_t primary_ssrc, uint32_t* fid_ssrc) const {
139 return GetSecondarySsrc(kFidSsrcGroupSemantics, primary_ssrc, fid_ssrc);
140 }
141
142 // Convenience to get all the SIM SSRCs if there are SIM ssrcs, or
143 // the first SSRC otherwise.
144 void GetPrimarySsrcs(std::vector<uint32_t>* ssrcs) const;
145
146 // Convenience to get all the FID SSRCs for the given primary ssrcs.
147 // If a given primary SSRC does not have a FID SSRC, the list of FID
148 // SSRCS will be smaller than the list of primary SSRCs.
149 void GetFidSsrcs(const std::vector<uint32_t>& primary_ssrcs,
150 std::vector<uint32_t>* fid_ssrcs) const;
151
152 std::string ToString() const;
153
154 // Resource of the MUC jid of the participant of with this stream.
155 // For 1:1 calls, should be left empty (which means remote streams
156 // and local streams should not be mixed together).
157 std::string groupid;
158 // Unique per-groupid, not across all groupids
159 std::string id;
160 std::vector<uint32_t> ssrcs; // All SSRCs for this source
161 std::vector<SsrcGroup> ssrc_groups; // e.g. FID, FEC, SIM
162 // Examples: "camera", "screencast"
163 std::string type;
164 // Friendly name describing stream
165 std::string display;
166 std::string cname; // RTCP CNAME
167 std::string sync_label; // Friendly name of cname.
168
169 private:
170 bool AddSecondarySsrc(const std::string& semantics,
171 uint32_t primary_ssrc,
172 uint32_t secondary_ssrc);
173 bool GetSecondarySsrc(const std::string& semantics,
174 uint32_t primary_ssrc,
175 uint32_t* secondary_ssrc) const;
176 };
177
178 // A Stream can be selected by either groupid+id or ssrc.
179 struct StreamSelector {
StreamSelectorStreamSelector180 explicit StreamSelector(uint32_t ssrc) : ssrc(ssrc) {}
181
StreamSelectorStreamSelector182 StreamSelector(const std::string& groupid,
183 const std::string& streamid) :
184 ssrc(0),
185 groupid(groupid),
186 streamid(streamid) {
187 }
188
MatchesStreamSelector189 bool Matches(const StreamParams& stream) const {
190 if (ssrc == 0) {
191 return stream.groupid == groupid && stream.id == streamid;
192 } else {
193 return stream.has_ssrc(ssrc);
194 }
195 }
196
197 uint32_t ssrc;
198 std::string groupid;
199 std::string streamid;
200 };
201
202 typedef std::vector<StreamParams> StreamParamsVec;
203
204 // A collection of audio and video and data streams. Most of the
205 // methods are merely for convenience. Many of these methods are keyed
206 // by ssrc, which is the source identifier in the RTP spec
207 // (http://tools.ietf.org/html/rfc3550).
208 // TODO(pthatcher): Add basic unit test for these.
209 // See https://code.google.com/p/webrtc/issues/detail?id=4107
210 struct MediaStreams {
211 public:
MediaStreamsMediaStreams212 MediaStreams() {}
213 void CopyFrom(const MediaStreams& sources);
214
emptyMediaStreams215 bool empty() const {
216 return audio_.empty() && video_.empty() && data_.empty();
217 }
218
mutable_audioMediaStreams219 std::vector<StreamParams>* mutable_audio() { return &audio_; }
mutable_videoMediaStreams220 std::vector<StreamParams>* mutable_video() { return &video_; }
mutable_dataMediaStreams221 std::vector<StreamParams>* mutable_data() { return &data_; }
audioMediaStreams222 const std::vector<StreamParams>& audio() const { return audio_; }
videoMediaStreams223 const std::vector<StreamParams>& video() const { return video_; }
dataMediaStreams224 const std::vector<StreamParams>& data() const { return data_; }
225
226 // Gets a stream, returning true if found.
227 bool GetAudioStream(
228 const StreamSelector& selector, StreamParams* stream);
229 bool GetVideoStream(
230 const StreamSelector& selector, StreamParams* stream);
231 bool GetDataStream(
232 const StreamSelector& selector, StreamParams* stream);
233 // Adds a stream.
234 void AddAudioStream(const StreamParams& stream);
235 void AddVideoStream(const StreamParams& stream);
236 void AddDataStream(const StreamParams& stream);
237 // Removes a stream, returning true if found and removed.
238 bool RemoveAudioStream(const StreamSelector& selector);
239 bool RemoveVideoStream(const StreamSelector& selector);
240 bool RemoveDataStream(const StreamSelector& selector);
241
242 private:
243 std::vector<StreamParams> audio_;
244 std::vector<StreamParams> video_;
245 std::vector<StreamParams> data_;
246
247 RTC_DISALLOW_COPY_AND_ASSIGN(MediaStreams);
248 };
249
250 // A request for a specific format of a specific stream.
251 struct StaticVideoView {
StaticVideoViewStaticVideoView252 StaticVideoView(const StreamSelector& selector,
253 int width, int height, int framerate)
254 : selector(selector),
255 width(width),
256 height(height),
257 framerate(framerate),
258 preference(0) {
259 }
260
261 StreamSelector selector;
262 int width;
263 int height;
264 int framerate;
265 int preference;
266 };
267
268 typedef std::vector<StaticVideoView> StaticVideoViews;
269
270 // A request for several streams in various formats.
271 struct ViewRequest {
272 StaticVideoViews static_video_views;
273 };
274
275 template <class Condition>
GetStream(const StreamParamsVec & streams,Condition condition)276 const StreamParams* GetStream(const StreamParamsVec& streams,
277 Condition condition) {
278 StreamParamsVec::const_iterator found =
279 std::find_if(streams.begin(), streams.end(), condition);
280 return found == streams.end() ? nullptr : &(*found);
281 }
282
GetStreamBySsrc(const StreamParamsVec & streams,uint32_t ssrc)283 inline const StreamParams* GetStreamBySsrc(const StreamParamsVec& streams,
284 uint32_t ssrc) {
285 return GetStream(streams,
286 [&ssrc](const StreamParams& sp) { return sp.has_ssrc(ssrc); });
287 }
288
GetStreamByIds(const StreamParamsVec & streams,const std::string & groupid,const std::string & id)289 inline const StreamParams* GetStreamByIds(const StreamParamsVec& streams,
290 const std::string& groupid,
291 const std::string& id) {
292 return GetStream(streams,
293 [&groupid, &id](const StreamParams& sp) {
294 return sp.groupid == groupid && sp.id == id;
295 });
296 }
297
GetStream(const StreamParamsVec & streams,const StreamSelector & selector)298 inline const StreamParams* GetStream(const StreamParamsVec& streams,
299 const StreamSelector& selector) {
300 return GetStream(streams,
301 [&selector](const StreamParams& sp) { return selector.Matches(sp); });
302 }
303
304 template <class Condition>
RemoveStream(StreamParamsVec * streams,Condition condition)305 bool RemoveStream(StreamParamsVec* streams, Condition condition) {
306 auto iter(std::remove_if(streams->begin(), streams->end(), condition));
307 if (iter == streams->end())
308 return false;
309 streams->erase(iter, streams->end());
310 return true;
311 }
312
313 // Removes the stream from streams. Returns true if a stream is
314 // found and removed.
RemoveStream(StreamParamsVec * streams,const StreamSelector & selector)315 inline bool RemoveStream(StreamParamsVec* streams,
316 const StreamSelector& selector) {
317 return RemoveStream(streams,
318 [&selector](const StreamParams& sp) { return selector.Matches(sp); });
319 }
RemoveStreamBySsrc(StreamParamsVec * streams,uint32_t ssrc)320 inline bool RemoveStreamBySsrc(StreamParamsVec* streams, uint32_t ssrc) {
321 return RemoveStream(streams,
322 [&ssrc](const StreamParams& sp) { return sp.has_ssrc(ssrc); });
323 }
RemoveStreamByIds(StreamParamsVec * streams,const std::string & groupid,const std::string & id)324 inline bool RemoveStreamByIds(StreamParamsVec* streams,
325 const std::string& groupid,
326 const std::string& id) {
327 return RemoveStream(streams,
328 [&groupid, &id](const StreamParams& sp) {
329 return sp.groupid == groupid && sp.id == id;
330 });
331 }
332
333 // Checks if |sp| defines parameters for a single primary stream. There may
334 // be an RTX stream associated with the primary stream. Leaving as non-static so
335 // we can test this function.
336 bool IsOneSsrcStream(const StreamParams& sp);
337
338 // Checks if |sp| defines parameters for one Simulcast stream. There may be RTX
339 // streams associated with the simulcast streams. Leaving as non-static so we
340 // can test this function.
341 bool IsSimulcastStream(const StreamParams& sp);
342
343 } // namespace cricket
344
345 #endif // TALK_MEDIA_BASE_STREAMPARAMS_H_
346