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/*
* libjingle
* Copyright 2011 Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// 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.
#ifndef TALK_MEDIA_BASE_STREAMPARAMS_H_
#define TALK_MEDIA_BASE_STREAMPARAMS_H_
#include <algorithm>
#include <string>
#include <set>
#include <vector>
#include "talk/base/basictypes.h"
namespace cricket {
extern const char kFecSsrcGroupSemantics[];
extern const char kFidSsrcGroupSemantics[];
extern const char kSimSsrcGroupSemantics[];
struct SsrcGroup {
SsrcGroup(const std::string& usage, const std::vector<uint32>& ssrcs)
: semantics(usage), ssrcs(ssrcs) {
}
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> ssrcs; // SSRCs of this type.
};
struct StreamParams {
static StreamParams CreateLegacy(uint32 ssrc) {
StreamParams stream;
stream.ssrcs.push_back(ssrc);
return stream;
}
bool operator==(const StreamParams& other) const {
return (groupid == other.groupid &&
id == other.id &&
ssrcs == other.ssrcs &&
ssrc_groups == other.ssrc_groups &&
type == other.type &&
display == other.display &&
cname == other.cname &&
sync_label == other.sync_label);
}
bool operator!=(const StreamParams &other) const {
return !(*this == other);
}
uint32 first_ssrc() const {
if (ssrcs.empty()) {
return 0;
}
return ssrcs[0];
}
bool has_ssrcs() const {
return !ssrcs.empty();
}
bool has_ssrc(uint32 ssrc) const {
return std::find(ssrcs.begin(), ssrcs.end(), ssrc) != ssrcs.end();
}
void add_ssrc(uint32 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.
inline bool AddFidSsrc(uint32 primary_ssrc, uint32 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.
inline bool GetFidSsrc(uint32 primary_ssrc, uint32* fid_ssrc) const {
return GetSecondarySsrc(kFidSsrcGroupSemantics, primary_ssrc, fid_ssrc);
}
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).
std::string groupid;
// Unique per-groupid, not across all groupids
std::string id;
std::vector<uint32> ssrcs; // All SSRCs for this source
std::vector<SsrcGroup> ssrc_groups; // e.g. FID, FEC, SIM
// Examples: "camera", "screencast"
std::string type;
// Friendly name describing stream
std::string display;
std::string cname; // RTCP CNAME
std::string sync_label; // Friendly name of cname.
private:
bool AddSecondarySsrc(const std::string& semantics, uint32 primary_ssrc,
uint32 secondary_ssrc);
bool GetSecondarySsrc(const std::string& semantics, uint32 primary_ssrc,
uint32* secondary_ssrc) const;
};
// A Stream can be selected by either groupid+id or ssrc.
struct StreamSelector {
explicit StreamSelector(uint32 ssrc) :
ssrc(ssrc) {
}
StreamSelector(const std::string& groupid,
const std::string& streamid) :
ssrc(0),
groupid(groupid),
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 ssrc;
std::string groupid;
std::string streamid;
};
typedef std::vector<StreamParams> StreamParamsVec;
// Finds the stream in streams. Returns true if found.
bool GetStream(const StreamParamsVec& streams,
const StreamSelector& selector,
StreamParams* stream_out);
bool GetStreamBySsrc(const StreamParamsVec& streams, uint32 ssrc,
StreamParams* stream_out);
bool GetStreamByIds(const StreamParamsVec& streams,
const std::string& groupid,
const std::string& id,
StreamParams* stream_out);
// Removes the stream from streams. Returns true if a stream is
// found and removed.
bool RemoveStream(StreamParamsVec* streams,
const StreamSelector& selector);
bool RemoveStreamBySsrc(StreamParamsVec* streams, uint32 ssrc);
bool RemoveStreamByIds(StreamParamsVec* streams,
const std::string& groupid,
const std::string& id);
// Checks if |sp| defines parameters for a single primary stream. There may
// be an RTX stream 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 // TALK_MEDIA_BASE_STREAMPARAMS_H_
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