1 /*
2 * Copyright (c) 2004 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #ifndef WEBRTC_MEDIA_BASE_CODEC_H_
12 #define WEBRTC_MEDIA_BASE_CODEC_H_
13
14 #include <map>
15 #include <set>
16 #include <string>
17 #include <vector>
18
19 #include "webrtc/api/rtpparameters.h"
20 #include "webrtc/common_types.h"
21 #include "webrtc/media/base/mediaconstants.h"
22
23 namespace cricket {
24
25 typedef std::map<std::string, std::string> CodecParameterMap;
26
27 class FeedbackParam {
28 public:
FeedbackParam(const std::string & id,const std::string & param)29 FeedbackParam(const std::string& id, const std::string& param)
30 : id_(id),
31 param_(param) {
32 }
FeedbackParam(const std::string & id)33 explicit FeedbackParam(const std::string& id)
34 : id_(id),
35 param_(kParamValueEmpty) {
36 }
37 bool operator==(const FeedbackParam& other) const;
38
id()39 const std::string& id() const { return id_; }
param()40 const std::string& param() const { return param_; }
41
42 private:
43 std::string id_; // e.g. "nack", "ccm"
44 std::string param_; // e.g. "", "rpsi", "fir"
45 };
46
47 class FeedbackParams {
48 public:
49 bool operator==(const FeedbackParams& other) const;
50
51 bool Has(const FeedbackParam& param) const;
52 void Add(const FeedbackParam& param);
53
54 void Intersect(const FeedbackParams& from);
55
params()56 const std::vector<FeedbackParam>& params() const { return params_; }
57 private:
58 bool HasDuplicateEntries() const;
59
60 std::vector<FeedbackParam> params_;
61 };
62
63 struct Codec {
64 int id;
65 std::string name;
66 int clockrate;
67 CodecParameterMap params;
68 FeedbackParams feedback_params;
69
70 virtual ~Codec();
71
72 // Indicates if this codec is compatible with the specified codec.
73 bool Matches(const Codec& codec) const;
74
75 // Find the parameter for |name| and write the value to |out|.
76 bool GetParam(const std::string& name, std::string* out) const;
77 bool GetParam(const std::string& name, int* out) const;
78
79 void SetParam(const std::string& name, const std::string& value);
80 void SetParam(const std::string& name, int value);
81
82 // It is safe to input a non-existent parameter.
83 // Returns true if the parameter existed, false if it did not exist.
84 bool RemoveParam(const std::string& name);
85
86 bool HasFeedbackParam(const FeedbackParam& param) const;
87 void AddFeedbackParam(const FeedbackParam& param);
88
89 // Filter |this| feedbacks params such that only those shared by both |this|
90 // and |other| are kept.
91 void IntersectFeedbackParams(const Codec& other);
92
93 virtual webrtc::RtpCodecParameters ToCodecParameters() const;
94
95 Codec& operator=(const Codec& c);
96 Codec& operator=(Codec&& c);
97
98 bool operator==(const Codec& c) const;
99
100 bool operator!=(const Codec& c) const {
101 return !(*this == c);
102 }
103
104 protected:
105 // A Codec can't be created without a subclass.
106 // Creates a codec with the given parameters.
107 Codec(int id, const std::string& name, int clockrate);
108 // Creates an empty codec.
109 Codec();
110 Codec(const Codec& c);
111 Codec(Codec&& c);
112 };
113
114 struct AudioCodec : public Codec {
115 int bitrate;
116 size_t channels;
117
118 // Creates a codec with the given parameters.
119 AudioCodec(int id,
120 const std::string& name,
121 int clockrate,
122 int bitrate,
123 size_t channels);
124 // Creates an empty codec.
125 AudioCodec();
126 AudioCodec(const AudioCodec& c);
127 AudioCodec(AudioCodec&& c);
128 virtual ~AudioCodec() = default;
129
130 // Indicates if this codec is compatible with the specified codec.
131 bool Matches(const AudioCodec& codec) const;
132
133 std::string ToString() const;
134
135 webrtc::RtpCodecParameters ToCodecParameters() const override;
136
137 AudioCodec& operator=(const AudioCodec& c);
138 AudioCodec& operator=(AudioCodec&& c);
139
140 bool operator==(const AudioCodec& c) const;
141
142 bool operator!=(const AudioCodec& c) const {
143 return !(*this == c);
144 }
145 };
146
147 struct VideoCodec : public Codec {
148 // Creates a codec with the given parameters.
149 VideoCodec(int id, const std::string& name);
150 // Creates a codec with the given name and empty id.
151 explicit VideoCodec(const std::string& name);
152 // Creates an empty codec.
153 VideoCodec();
154 VideoCodec(const VideoCodec& c);
155 VideoCodec(VideoCodec&& c);
156 virtual ~VideoCodec() = default;
157
158 // Indicates if this video codec is the same as the other video codec, e.g. if
159 // they are both VP8 or VP9, or if they are both H264 with the same H264
160 // profile. H264 levels however are not compared.
161 bool Matches(const VideoCodec& codec) const;
162
163 std::string ToString() const;
164
165 VideoCodec& operator=(const VideoCodec& c);
166 VideoCodec& operator=(VideoCodec&& c);
167
168 bool operator==(const VideoCodec& c) const;
169
170 bool operator!=(const VideoCodec& c) const {
171 return !(*this == c);
172 }
173
174 static VideoCodec CreateRtxCodec(int rtx_payload_type,
175 int associated_payload_type);
176
177 enum CodecType {
178 CODEC_VIDEO,
179 CODEC_RED,
180 CODEC_ULPFEC,
181 CODEC_FLEXFEC,
182 CODEC_RTX,
183 };
184
185 CodecType GetCodecType() const;
186 // Validates a VideoCodec's payload type, dimensions and bitrates etc. If they
187 // don't make sense (such as max < min bitrate), and error is logged and
188 // ValidateCodecFormat returns false.
189 bool ValidateCodecFormat() const;
190
191 private:
192 void SetDefaultParameters();
193 };
194
195 struct DataCodec : public Codec {
196 DataCodec(int id, const std::string& name);
197 DataCodec();
198 DataCodec(const DataCodec& c);
199 DataCodec(DataCodec&& c);
200 virtual ~DataCodec() = default;
201
202 DataCodec& operator=(const DataCodec& c);
203 DataCodec& operator=(DataCodec&& c);
204
205 std::string ToString() const;
206 };
207
208 // Get the codec setting associated with |payload_type|. If there
209 // is no codec associated with that payload type it returns nullptr.
210 template <class Codec>
FindCodecById(const std::vector<Codec> & codecs,int payload_type)211 const Codec* FindCodecById(const std::vector<Codec>& codecs, int payload_type) {
212 for (const auto& codec : codecs) {
213 if (codec.id == payload_type)
214 return &codec;
215 }
216 return nullptr;
217 }
218
219 bool CodecNamesEq(const std::string& name1, const std::string& name2);
220 bool CodecNamesEq(const char* name1, const char* name2);
221 bool HasNack(const Codec& codec);
222 bool HasRemb(const Codec& codec);
223 bool HasTransportCc(const Codec& codec);
224 // Returns the first codec in |supported_codecs| that matches |codec|, or
225 // nullptr if no codec matches.
226 const VideoCodec* FindMatchingCodec(
227 const std::vector<VideoCodec>& supported_codecs,
228 const VideoCodec& codec);
229
230 } // namespace cricket
231
232 #endif // WEBRTC_MEDIA_BASE_CODEC_H_
233