1/*
2 * libjingle
3 * Copyright 2013, 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/app/webrtc/mediaconstraintsinterface.h"
29
30#include "webrtc/base/stringencode.h"
31
32namespace webrtc {
33
34const char MediaConstraintsInterface::kValueTrue[] = "true";
35const char MediaConstraintsInterface::kValueFalse[] = "false";
36
37// Constraints declared as static members in mediastreaminterface.h
38// Specified by draft-alvestrand-constraints-resolution-00b
39const char MediaConstraintsInterface::kMinAspectRatio[] = "minAspectRatio";
40const char MediaConstraintsInterface::kMaxAspectRatio[] = "maxAspectRatio";
41const char MediaConstraintsInterface::kMaxWidth[] = "maxWidth";
42const char MediaConstraintsInterface::kMinWidth[] = "minWidth";
43const char MediaConstraintsInterface::kMaxHeight[] = "maxHeight";
44const char MediaConstraintsInterface::kMinHeight[] = "minHeight";
45const char MediaConstraintsInterface::kMaxFrameRate[] = "maxFrameRate";
46const char MediaConstraintsInterface::kMinFrameRate[] = "minFrameRate";
47
48// Audio constraints.
49const char MediaConstraintsInterface::kEchoCancellation[] =
50    "googEchoCancellation";
51const char MediaConstraintsInterface::kExperimentalEchoCancellation[] =
52    "googEchoCancellation2";
53const char MediaConstraintsInterface::kAutoGainControl[] =
54    "googAutoGainControl";
55const char MediaConstraintsInterface::kExperimentalAutoGainControl[] =
56    "googAutoGainControl2";
57const char MediaConstraintsInterface::kNoiseSuppression[] =
58    "googNoiseSuppression";
59const char MediaConstraintsInterface::kExperimentalNoiseSuppression[] =
60    "googNoiseSuppression2";
61const char MediaConstraintsInterface::kHighpassFilter[] =
62    "googHighpassFilter";
63const char MediaConstraintsInterface::kTypingNoiseDetection[] =
64    "googTypingNoiseDetection";
65const char MediaConstraintsInterface::kAudioMirroring[] = "googAudioMirroring";
66
67// Google-specific constraint keys for a local video source (getUserMedia).
68const char MediaConstraintsInterface::kNoiseReduction[] = "googNoiseReduction";
69const char MediaConstraintsInterface::kLeakyBucket[] = "googLeakyBucket";
70const char MediaConstraintsInterface::kTemporalLayeredScreencast[] =
71    "googTemporalLayeredScreencast";
72
73// Constraint keys for CreateOffer / CreateAnswer defined in W3C specification.
74const char MediaConstraintsInterface::kOfferToReceiveAudio[] =
75    "OfferToReceiveAudio";
76const char MediaConstraintsInterface::kOfferToReceiveVideo[] =
77    "OfferToReceiveVideo";
78const char MediaConstraintsInterface::kVoiceActivityDetection[] =
79    "VoiceActivityDetection";
80const char MediaConstraintsInterface::kIceRestart[] =
81    "IceRestart";
82// Google specific constraint for BUNDLE enable/disable.
83const char MediaConstraintsInterface::kUseRtpMux[] =
84    "googUseRtpMUX";
85
86// Below constraints should be used during PeerConnection construction.
87const char MediaConstraintsInterface::kEnableDtlsSrtp[] =
88    "DtlsSrtpKeyAgreement";
89const char MediaConstraintsInterface::kEnableRtpDataChannels[] =
90    "RtpDataChannels";
91// Google-specific constraint keys.
92const char MediaConstraintsInterface::kEnableDscp[] = "googDscp";
93const char MediaConstraintsInterface::kEnableIPv6[] = "googIPv6";
94const char MediaConstraintsInterface::kEnableVideoSuspendBelowMinBitrate[] =
95    "googSuspendBelowMinBitrate";
96const char MediaConstraintsInterface::kNumUnsignalledRecvStreams[] =
97    "googNumUnsignalledRecvStreams";
98const char MediaConstraintsInterface::kCombinedAudioVideoBwe[] =
99    "googCombinedAudioVideoBwe";
100const char MediaConstraintsInterface::kScreencastMinBitrate[] =
101    "googScreencastMinBitrate";
102// TODO(ronghuawu): Remove once cpu overuse detection is stable.
103const char MediaConstraintsInterface::kCpuOveruseDetection[] =
104    "googCpuOveruseDetection";
105const char MediaConstraintsInterface::kCpuUnderuseThreshold[] =
106    "googCpuUnderuseThreshold";
107const char MediaConstraintsInterface::kCpuOveruseThreshold[] =
108    "googCpuOveruseThreshold";
109const char MediaConstraintsInterface::kCpuUnderuseEncodeRsdThreshold[] =
110    "googCpuUnderuseEncodeRsdThreshold";
111const char MediaConstraintsInterface::kCpuOveruseEncodeRsdThreshold[] =
112    "googCpuOveruseEncodeRsdThreshold";
113const char MediaConstraintsInterface::kCpuOveruseEncodeUsage[] =
114    "googCpuOveruseEncodeUsage";
115const char MediaConstraintsInterface::kHighStartBitrate[] =
116    "googHighStartBitrate";
117const char MediaConstraintsInterface::kHighBitrate[] =
118    "googHighBitrate";
119const char MediaConstraintsInterface::kVeryHighBitrate[] =
120    "googVeryHighBitrate";
121const char MediaConstraintsInterface::kPayloadPadding[] = "googPayloadPadding";
122
123
124// Set |value| to the value associated with the first appearance of |key|, or
125// return false if |key| is not found.
126bool MediaConstraintsInterface::Constraints::FindFirst(
127    const std::string& key, std::string* value) const {
128  for (Constraints::const_iterator iter = begin(); iter != end(); ++iter) {
129    if (iter->key == key) {
130      *value = iter->value;
131      return true;
132    }
133  }
134  return false;
135}
136
137// Find the highest-priority instance of the boolean-valued constraint) named by
138// |key| and return its value as |value|. |constraints| can be null.
139// If |mandatory_constraints| is non-null, it is incremented if the key appears
140// among the mandatory constraints.
141// Returns true if the key was found and has a valid boolean value.
142// If the key appears multiple times as an optional constraint, appearances
143// after the first are ignored.
144// Note: Because this uses FindFirst, repeated optional constraints whose
145// first instance has an unrecognized value are not handled precisely in
146// accordance with the specification.
147bool FindConstraint(const MediaConstraintsInterface* constraints,
148                    const std::string& key, bool* value,
149                    size_t* mandatory_constraints) {
150  std::string string_value;
151  if (!constraints) {
152    return false;
153  }
154  if (constraints->GetMandatory().FindFirst(key, &string_value)) {
155    if (mandatory_constraints)
156      ++*mandatory_constraints;
157    return rtc::FromString(string_value, value);
158  }
159  if (constraints->GetOptional().FindFirst(key, &string_value)) {
160    return rtc::FromString(string_value, value);
161  }
162  return false;
163}
164
165}  // namespace webrtc
166