1 /*
2  *  Copyright (c) 2017 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 #include "api/audio_codecs/g722/audio_encoder_g722.h"
12 
13 #include <memory>
14 #include <vector>
15 
16 #include "absl/strings/match.h"
17 #include "modules/audio_coding/codecs/g722/audio_encoder_g722.h"
18 #include "rtc_base/numerics/safe_conversions.h"
19 #include "rtc_base/numerics/safe_minmax.h"
20 #include "rtc_base/string_to_number.h"
21 
22 namespace webrtc {
23 
SdpToConfig(const SdpAudioFormat & format)24 absl::optional<AudioEncoderG722Config> AudioEncoderG722::SdpToConfig(
25     const SdpAudioFormat& format) {
26   if (!absl::EqualsIgnoreCase(format.name, "g722") ||
27       format.clockrate_hz != 8000) {
28     return absl::nullopt;
29   }
30 
31   AudioEncoderG722Config config;
32   config.num_channels = rtc::checked_cast<int>(format.num_channels);
33   auto ptime_iter = format.parameters.find("ptime");
34   if (ptime_iter != format.parameters.end()) {
35     auto ptime = rtc::StringToNumber<int>(ptime_iter->second);
36     if (ptime && *ptime > 0) {
37       const int whole_packets = *ptime / 10;
38       config.frame_size_ms = rtc::SafeClamp<int>(whole_packets * 10, 10, 60);
39     }
40   }
41   return config.IsOk() ? absl::optional<AudioEncoderG722Config>(config)
42                        : absl::nullopt;
43 }
44 
AppendSupportedEncoders(std::vector<AudioCodecSpec> * specs)45 void AudioEncoderG722::AppendSupportedEncoders(
46     std::vector<AudioCodecSpec>* specs) {
47   const SdpAudioFormat fmt = {"G722", 8000, 1};
48   const AudioCodecInfo info = QueryAudioEncoder(*SdpToConfig(fmt));
49   specs->push_back({fmt, info});
50 }
51 
QueryAudioEncoder(const AudioEncoderG722Config & config)52 AudioCodecInfo AudioEncoderG722::QueryAudioEncoder(
53     const AudioEncoderG722Config& config) {
54   RTC_DCHECK(config.IsOk());
55   return {16000, rtc::dchecked_cast<size_t>(config.num_channels),
56           64000 * config.num_channels};
57 }
58 
MakeAudioEncoder(const AudioEncoderG722Config & config,int payload_type,absl::optional<AudioCodecPairId>)59 std::unique_ptr<AudioEncoder> AudioEncoderG722::MakeAudioEncoder(
60     const AudioEncoderG722Config& config,
61     int payload_type,
62     absl::optional<AudioCodecPairId> /*codec_pair_id*/) {
63   RTC_DCHECK(config.IsOk());
64   return std::make_unique<AudioEncoderG722Impl>(config, payload_type);
65 }
66 
67 }  // namespace webrtc
68