1 /*
2  * libjingle
3  * Copyright 2004 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 #include "talk/media/base/codec.h"
29 
30 #include <algorithm>
31 #include <sstream>
32 
33 #include "webrtc/base/common.h"
34 #include "webrtc/base/logging.h"
35 #include "webrtc/base/stringencode.h"
36 #include "webrtc/base/stringutils.h"
37 
38 namespace cricket {
39 
40 const int kMaxPayloadId = 127;
41 
operator ==(const FeedbackParam & other) const42 bool FeedbackParam::operator==(const FeedbackParam& other) const {
43   return _stricmp(other.id().c_str(), id().c_str()) == 0 &&
44       _stricmp(other.param().c_str(), param().c_str()) == 0;
45 }
46 
operator ==(const FeedbackParams & other) const47 bool FeedbackParams::operator==(const FeedbackParams& other) const {
48   return params_ == other.params_;
49 }
50 
Has(const FeedbackParam & param) const51 bool FeedbackParams::Has(const FeedbackParam& param) const {
52   return std::find(params_.begin(), params_.end(), param) != params_.end();
53 }
54 
Add(const FeedbackParam & param)55 void FeedbackParams::Add(const FeedbackParam& param) {
56   if (param.id().empty()) {
57     return;
58   }
59   if (Has(param)) {
60     // Param already in |this|.
61     return;
62   }
63   params_.push_back(param);
64   ASSERT(!HasDuplicateEntries());
65 }
66 
Intersect(const FeedbackParams & from)67 void FeedbackParams::Intersect(const FeedbackParams& from) {
68   std::vector<FeedbackParam>::iterator iter_to = params_.begin();
69   while (iter_to != params_.end()) {
70     if (!from.Has(*iter_to)) {
71       iter_to = params_.erase(iter_to);
72     } else {
73       ++iter_to;
74     }
75   }
76 }
77 
HasDuplicateEntries() const78 bool FeedbackParams::HasDuplicateEntries() const {
79   for (std::vector<FeedbackParam>::const_iterator iter = params_.begin();
80        iter != params_.end(); ++iter) {
81     for (std::vector<FeedbackParam>::const_iterator found = iter + 1;
82          found != params_.end(); ++found) {
83       if (*found == *iter) {
84         return true;
85       }
86     }
87   }
88   return false;
89 }
90 
Codec(int id,const std::string & name,int clockrate,int preference)91 Codec::Codec(int id, const std::string& name, int clockrate, int preference)
92     : id(id), name(name), clockrate(clockrate), preference(preference) {
93 }
94 
Codec()95 Codec::Codec() : id(0), clockrate(0), preference(0) {
96 }
97 
98 Codec::Codec(const Codec& c) = default;
99 
100 Codec::~Codec() = default;
101 
operator =(const Codec & c)102 Codec& Codec::operator=(const Codec& c) {
103   this->id = c.id;  // id is reserved in objective-c
104   name = c.name;
105   clockrate = c.clockrate;
106   preference = c.preference;
107   params = c.params;
108   feedback_params = c.feedback_params;
109   return *this;
110 }
111 
operator ==(const Codec & c) const112 bool Codec::operator==(const Codec& c) const {
113   return this->id == c.id &&  // id is reserved in objective-c
114          name == c.name && clockrate == c.clockrate &&
115          preference == c.preference && params == c.params &&
116          feedback_params == c.feedback_params;
117 }
118 
Matches(const Codec & codec) const119 bool Codec::Matches(const Codec& codec) const {
120   // Match the codec id/name based on the typical static/dynamic name rules.
121   // Matching is case-insensitive.
122   const int kMaxStaticPayloadId = 95;
123   return (codec.id <= kMaxStaticPayloadId) ?
124       (id == codec.id) : (_stricmp(name.c_str(), codec.name.c_str()) == 0);
125 }
126 
GetParam(const std::string & name,std::string * out) const127 bool Codec::GetParam(const std::string& name, std::string* out) const {
128   CodecParameterMap::const_iterator iter = params.find(name);
129   if (iter == params.end())
130     return false;
131   *out = iter->second;
132   return true;
133 }
134 
GetParam(const std::string & name,int * out) const135 bool Codec::GetParam(const std::string& name, int* out) const {
136   CodecParameterMap::const_iterator iter = params.find(name);
137   if (iter == params.end())
138     return false;
139   return rtc::FromString(iter->second, out);
140 }
141 
SetParam(const std::string & name,const std::string & value)142 void Codec::SetParam(const std::string& name, const std::string& value) {
143   params[name] = value;
144 }
145 
SetParam(const std::string & name,int value)146 void Codec::SetParam(const std::string& name, int value)  {
147   params[name] = rtc::ToString(value);
148 }
149 
RemoveParam(const std::string & name)150 bool Codec::RemoveParam(const std::string& name) {
151   return params.erase(name) == 1;
152 }
153 
AddFeedbackParam(const FeedbackParam & param)154 void Codec::AddFeedbackParam(const FeedbackParam& param) {
155   feedback_params.Add(param);
156 }
157 
HasFeedbackParam(const FeedbackParam & param) const158 bool Codec::HasFeedbackParam(const FeedbackParam& param) const {
159   return feedback_params.Has(param);
160 }
161 
IntersectFeedbackParams(const Codec & other)162 void Codec::IntersectFeedbackParams(const Codec& other) {
163   feedback_params.Intersect(other.feedback_params);
164 }
165 
AudioCodec(int id,const std::string & name,int clockrate,int bitrate,size_t channels,int preference)166 AudioCodec::AudioCodec(int id,
167                        const std::string& name,
168                        int clockrate,
169                        int bitrate,
170                        size_t channels,
171                        int preference)
172     : Codec(id, name, clockrate, preference),
173       bitrate(bitrate),
174       channels(channels) {
175 }
176 
AudioCodec()177 AudioCodec::AudioCodec() : Codec(), bitrate(0), channels(0) {
178 }
179 
180 AudioCodec::AudioCodec(const AudioCodec& c) = default;
181 
operator =(const AudioCodec & c)182 AudioCodec& AudioCodec::operator=(const AudioCodec& c) {
183   Codec::operator=(c);
184   bitrate = c.bitrate;
185   channels = c.channels;
186   return *this;
187 }
188 
operator ==(const AudioCodec & c) const189 bool AudioCodec::operator==(const AudioCodec& c) const {
190   return bitrate == c.bitrate && channels == c.channels && Codec::operator==(c);
191 }
192 
Matches(const AudioCodec & codec) const193 bool AudioCodec::Matches(const AudioCodec& codec) const {
194   // If a nonzero clockrate is specified, it must match the actual clockrate.
195   // If a nonzero bitrate is specified, it must match the actual bitrate,
196   // unless the codec is VBR (0), where we just force the supplied value.
197   // The number of channels must match exactly, with the exception
198   // that channels=0 is treated synonymously as channels=1, per RFC
199   // 4566 section 6: " [The channels] parameter is OPTIONAL and may be
200   // omitted if the number of channels is one."
201   // Preference is ignored.
202   // TODO(juberti): Treat a zero clockrate as 8000Hz, the RTP default clockrate.
203   return Codec::Matches(codec) &&
204       ((codec.clockrate == 0 /*&& clockrate == 8000*/) ||
205           clockrate == codec.clockrate) &&
206       (codec.bitrate == 0 || bitrate <= 0 || bitrate == codec.bitrate) &&
207       ((codec.channels < 2 && channels < 2) || channels == codec.channels);
208 }
209 
ToString() const210 std::string AudioCodec::ToString() const {
211   std::ostringstream os;
212   os << "AudioCodec[" << id << ":" << name << ":" << clockrate << ":" << bitrate
213      << ":" << channels << ":" << preference << "]";
214   return os.str();
215 }
216 
ToString() const217 std::string VideoCodec::ToString() const {
218   std::ostringstream os;
219   os << "VideoCodec[" << id << ":" << name << ":" << width << ":" << height
220      << ":" << framerate << ":" << preference << "]";
221   return os.str();
222 }
223 
VideoCodec(int id,const std::string & name,int width,int height,int framerate,int preference)224 VideoCodec::VideoCodec(int id,
225                        const std::string& name,
226                        int width,
227                        int height,
228                        int framerate,
229                        int preference)
230     : Codec(id, name, kVideoCodecClockrate, preference),
231       width(width),
232       height(height),
233       framerate(framerate) {
234 }
235 
VideoCodec(int id,const std::string & name)236 VideoCodec::VideoCodec(int id, const std::string& name)
237     : Codec(id, name, kVideoCodecClockrate, 0),
238       width(0),
239       height(0),
240       framerate(0) {
241 }
242 
VideoCodec()243 VideoCodec::VideoCodec() : Codec(), width(0), height(0), framerate(0) {
244   clockrate = kVideoCodecClockrate;
245 }
246 
247 VideoCodec::VideoCodec(const VideoCodec& c) = default;
248 
operator =(const VideoCodec & c)249 VideoCodec& VideoCodec::operator=(const VideoCodec& c) {
250   Codec::operator=(c);
251   width = c.width;
252   height = c.height;
253   framerate = c.framerate;
254   return *this;
255 }
256 
operator ==(const VideoCodec & c) const257 bool VideoCodec::operator==(const VideoCodec& c) const {
258   return width == c.width && height == c.height && framerate == c.framerate &&
259          Codec::operator==(c);
260 }
261 
CreateRtxCodec(int rtx_payload_type,int associated_payload_type)262 VideoCodec VideoCodec::CreateRtxCodec(int rtx_payload_type,
263                                       int associated_payload_type) {
264   VideoCodec rtx_codec(rtx_payload_type, kRtxCodecName, 0, 0, 0, 0);
265   rtx_codec.SetParam(kCodecParamAssociatedPayloadType, associated_payload_type);
266   return rtx_codec;
267 }
268 
GetCodecType() const269 VideoCodec::CodecType VideoCodec::GetCodecType() const {
270   const char* payload_name = name.c_str();
271   if (_stricmp(payload_name, kRedCodecName) == 0) {
272     return CODEC_RED;
273   }
274   if (_stricmp(payload_name, kUlpfecCodecName) == 0) {
275     return CODEC_ULPFEC;
276   }
277   if (_stricmp(payload_name, kRtxCodecName) == 0) {
278     return CODEC_RTX;
279   }
280 
281   return CODEC_VIDEO;
282 }
283 
ValidateCodecFormat() const284 bool VideoCodec::ValidateCodecFormat() const {
285   if (id < 0 || id > 127) {
286     LOG(LS_ERROR) << "Codec with invalid payload type: " << ToString();
287     return false;
288   }
289   if (GetCodecType() != CODEC_VIDEO) {
290     return true;
291   }
292 
293   // Video validation from here on.
294 
295   if (width <= 0 || height <= 0) {
296     LOG(LS_ERROR) << "Codec with invalid dimensions: " << ToString();
297     return false;
298   }
299   int min_bitrate = -1;
300   int max_bitrate = -1;
301   if (GetParam(kCodecParamMinBitrate, &min_bitrate) &&
302       GetParam(kCodecParamMaxBitrate, &max_bitrate)) {
303     if (max_bitrate < min_bitrate) {
304       LOG(LS_ERROR) << "Codec with max < min bitrate: " << ToString();
305       return false;
306     }
307   }
308   return true;
309 }
310 
DataCodec(int id,const std::string & name,int preference)311 DataCodec::DataCodec(int id, const std::string& name, int preference)
312     : Codec(id, name, kDataCodecClockrate, preference) {
313 }
314 
DataCodec()315 DataCodec::DataCodec() : Codec() {
316   clockrate = kDataCodecClockrate;
317 }
318 
319 DataCodec::DataCodec(const DataCodec& c) = default;
320 
321 DataCodec& DataCodec::operator=(const DataCodec& c) = default;
322 
ToString() const323 std::string DataCodec::ToString() const {
324   std::ostringstream os;
325   os << "DataCodec[" << id << ":" << name << "]";
326   return os.str();
327 }
328 
HasNack(const VideoCodec & codec)329 bool HasNack(const VideoCodec& codec) {
330   return codec.HasFeedbackParam(
331       FeedbackParam(kRtcpFbParamNack, kParamValueEmpty));
332 }
333 
HasRemb(const VideoCodec & codec)334 bool HasRemb(const VideoCodec& codec) {
335   return codec.HasFeedbackParam(
336       FeedbackParam(kRtcpFbParamRemb, kParamValueEmpty));
337 }
338 
HasTransportCc(const VideoCodec & codec)339 bool HasTransportCc(const VideoCodec& codec) {
340   return codec.HasFeedbackParam(
341       FeedbackParam(kRtcpFbParamTransportCc, kParamValueEmpty));
342 }
343 
CodecNamesEq(const std::string & name1,const std::string & name2)344 bool CodecNamesEq(const std::string& name1, const std::string& name2) {
345   return _stricmp(name1.c_str(), name2.c_str()) == 0;
346 }
347 
348 }  // namespace cricket
349