G711 implementation of the Audio{En,De}coderFactoryTemplate APIs

webrtc/api/audio_codecs/g711/audio_decoder_g711.cc

+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/api/audio_codecs/g711/audio_decoder_g711.h"
+
+#include <memory>
+#include <vector>
+
+#include "webrtc/common_types.h"
+#include "webrtc/modules/audio_coding/codecs/g711/audio_decoder_pcm.h"
+#include "webrtc/rtc_base/ptr_util.h"
+#include "webrtc/rtc_base/safe_conversions.h"
+
+namespace webrtc {
+
+rtc::Optional<AudioDecoderG711::Config> AudioDecoderG711::SdpToConfig(
+    const SdpAudioFormat& format) {
+  const bool is_pcmu = STR_CASE_CMP(format.name.c_str(), "PCMU") == 0;
+  const bool is_pcma = STR_CASE_CMP(format.name.c_str(), "PCMA") == 0;
+  if (format.clockrate_hz == 8000 && format.num_channels >= 1 &&
+      (is_pcmu || is_pcma)) {
+    Config config;
+    config.type = is_pcmu ? Config::Type::kPcmU : Config::Type::kPcmA;
+    config.num_channels = rtc::dchecked_cast<int>(format.num_channels);
+    RTC_DCHECK(config.IsOk());
+    return rtc::Optional<Config>(config);
+  } else {
+    return rtc::Optional<Config>();
+  }
+}
+
+void AudioDecoderG711::AppendSupportedDecoders(
+    std::vector<AudioCodecSpec>* specs) {
+  for (const char* type : {"PCMU", "PCMA"}) {
+    specs->push_back({{type, 8000, 1}, {8000, 1, 64000}});
+  }
+}
+
+std::unique_ptr<AudioDecoder> AudioDecoderG711::MakeAudioDecoder(
+    const Config& config) {
+  RTC_DCHECK(config.IsOk());
+  switch (config.type) {
+    case Config::Type::kPcmU:
+      return rtc::MakeUnique<AudioDecoderPcmU>(config.num_channels);
+    case Config::Type::kPcmA:
+      return rtc::MakeUnique<AudioDecoderPcmA>(config.num_channels);
+    default:
+      return nullptr;
+  }
+}
+
+}  // namespace webrtc