webrtc-sys 0.2.1-alpha

Unsafe bindings to libwebrtc
Documentation
/*
 * Copyright 2023 LiveKit
 *
 * Licensed under the Apache License, Version 2.0 (the “License”);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an “AS IS” BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "livekit/video_encoder_factory.h"

#include "api/video_codecs/sdp_video_format.h"
#include "api/video_codecs/video_encoder.h"
#include "api/video_codecs/video_encoder_factory_template.h"
#include "api/video_codecs/video_encoder_factory_template_libvpx_vp8_adapter.h"
#include "livekit/objc_video_factory.h"
#include "media/base/media_constants.h"
#include "media/engine/simulcast_encoder_adapter.h"
#include "rtc_base/logging.h"

#if defined(WEBRTC_USE_H264)
#include "api/video_codecs/video_encoder_factory_template_open_h264_adapter.h"
#endif

#ifdef WEBRTC_ANDROID
#include "livekit/android.h"
#endif

namespace livekit {

using Factory =
    webrtc::VideoEncoderFactoryTemplate<webrtc::LibvpxVp8EncoderTemplateAdapter
#if defined(WEBRTC_USE_H264)
                                        ,
                                        webrtc::OpenH264EncoderTemplateAdapter
#endif
                                        >;

VideoEncoderFactory::InternalFactory::InternalFactory() {
#ifdef __APPLE__
  factories_.push_back(livekit::CreateObjCVideoEncoderFactory());
#endif

#ifdef WEBRTC_ANDROID
  factories_.push_back(CreateAndroidVideoEncoderFactory());
#endif

  // TODO(theomonnom): Add other HW encoders here
}

std::vector<webrtc::SdpVideoFormat>
VideoEncoderFactory::InternalFactory::GetSupportedFormats() const {
  std::vector<webrtc::SdpVideoFormat> formats = Factory().GetSupportedFormats();

  for (const auto& factory : factories_) {
    auto supported_formats = factory->GetSupportedFormats();
    formats.insert(formats.end(), supported_formats.begin(),
                   supported_formats.end());
  }
  return formats;
}

VideoEncoderFactory::CodecSupport
VideoEncoderFactory::InternalFactory::QueryCodecSupport(
    const webrtc::SdpVideoFormat& format,
    absl::optional<std::string> scalability_mode) const {
  auto original_format =
      webrtc::FuzzyMatchSdpVideoFormat(Factory().GetSupportedFormats(), format);
  return original_format
             ? Factory().QueryCodecSupport(*original_format, scalability_mode)
             : webrtc::VideoEncoderFactory::CodecSupport{.is_supported = false};
}

std::unique_ptr<webrtc::VideoEncoder>
VideoEncoderFactory::InternalFactory::CreateVideoEncoder(
    const webrtc::SdpVideoFormat& format) {
  for (const auto& factory : factories_) {
    for (const auto& supported_format : factory->GetSupportedFormats()) {
      if (supported_format.IsSameCodec(format))
        return factory->CreateVideoEncoder(format);
    }
  }

  auto original_format =
      webrtc::FuzzyMatchSdpVideoFormat(Factory().GetSupportedFormats(), format);

  if (original_format) {
    return Factory().CreateVideoEncoder(*original_format);
  }

  RTC_LOG(LS_ERROR) << "No VideoEncoder found for " << format.name;
  return nullptr;
}

VideoEncoderFactory::VideoEncoderFactory() {
  internal_factory_ = std::make_unique<InternalFactory>();
}

std::vector<webrtc::SdpVideoFormat> VideoEncoderFactory::GetSupportedFormats()
    const {
  return internal_factory_->GetSupportedFormats();
}

VideoEncoderFactory::CodecSupport VideoEncoderFactory::QueryCodecSupport(
    const webrtc::SdpVideoFormat& format,
    absl::optional<std::string> scalability_mode) const {
  return internal_factory_->QueryCodecSupport(format, scalability_mode);
}

std::unique_ptr<webrtc::VideoEncoder> VideoEncoderFactory::CreateVideoEncoder(
    const webrtc::SdpVideoFormat& format) {
  std::unique_ptr<webrtc::VideoEncoder> encoder;
  if (format.IsCodecInList(internal_factory_->GetSupportedFormats())) {
    encoder = std::make_unique<webrtc::SimulcastEncoderAdapter>(
        internal_factory_.get(), format);
  }

  return encoder;
}

}  // namespace livekit