VideoToolBox decoder/encoder for MacOS & iOS (#19)

* VideoDecoderFactory wrapper

* wip

* fix compilation

* add notes

* upgrade webrtc version

webrtc-sys/include/livekit/objc_video_factory.h

@@ -0,0 +1,15 @@
+#ifndef OBJC_VIDEO_FACTORY_H
+#define OBJC_VIDEO_FACTORY_H
+
+#include <memory>
+#include "api/video_codecs/video_decoder_factory.h"
+#include "api/video_codecs/video_encoder_factory.h"
+
+namespace livekit {
+
+std::unique_ptr<webrtc::VideoEncoderFactory> CreateObjCVideoEncoderFactory();
+std::unique_ptr<webrtc::VideoDecoderFactory> CreateObjCVideoDecoderFactory();
+
+}  // namespace livekit
+
+#endif // OBJC_VIDEO_FACTORY_H

webrtc-sys/include/livekit/video_decoder_factory.h

@@ -0,0 +1,22 @@
+#ifndef VIDEO_DECODER_FACTORY_H
+#define VIDEO_DECODER_FACTORY_H
+
+#include "api/video_codecs/video_decoder_factory.h"
+#include "api/video_codecs/video_decoder.h"
+
+namespace livekit {
+class VideoDecoderFactory : public webrtc::VideoDecoderFactory {
+ public:
+  VideoDecoderFactory();
+
+  std::vector<webrtc::SdpVideoFormat> GetSupportedFormats() const override;
+
+  std::unique_ptr<webrtc::VideoDecoder> CreateVideoDecoder(
+      const webrtc::SdpVideoFormat& format) override;
+
+ private:
+  std::vector<std::unique_ptr<webrtc::VideoDecoderFactory>> factories_;
+};
+}  // namespace livekit
+
+#endif  // VIDEO_DECODER_FACTORY_H

webrtc-sys/include/livekit/video_encoder_factory.h

@@ -0,0 +1,22 @@
+#ifndef VIDEO_ENCODER_FACTORY_H
+#define VIDEO_ENCODER_FACTORY_H
+
+#include "api/video_codecs/video_encoder_factory.h"
+#include "api/video_codecs/video_encoder.h"
+
+namespace livekit {
+class VideoEncoderFactory : public webrtc::VideoEncoderFactory {
+ public:
+  VideoEncoderFactory();
+
+  std::vector<webrtc::SdpVideoFormat> GetSupportedFormats() const override;
+
+  std::unique_ptr<webrtc::VideoEncoder> CreateVideoEncoder(
+      const webrtc::SdpVideoFormat& format) override;
+
+ private:
+  std::vector<std::unique_ptr<webrtc::VideoEncoderFactory>> factories_;
+};
+}  // namespace livekit
+
+#endif  // VIDEO_ENCODER_FACTORY_H