Motown: Video renderer library code

mojo/services/media/common/cpp/video_renderer.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MOJO_SERVICES_MEDIA_COMMON_CPP_VIDEO_RENDERER_H_
+#define MOJO_SERVICES_MEDIA_COMMON_CPP_VIDEO_RENDERER_H_
+
+#include <memory>
+#include <queue>
+
+#include "mojo/public/cpp/bindings/binding.h"
+#include "mojo/services/media/common/cpp/mapped_shared_buffer.h"
+#include "mojo/services/media/common/cpp/timeline_function.h"
+#include "mojo/services/media/common/cpp/video_converter.h"
+#include "mojo/services/media/common/interfaces/media_transport.mojom.h"
+#include "mojo/services/media/core/interfaces/media_renderer.mojom.h"
+
+namespace mojo {
+namespace media {
+
+// Implements MediaRenderer for an app that wants to show video.
+class VideoRenderer : public MediaRenderer,
+                      public MediaConsumer,
+                      public MediaTimelineControlSite,
+                      public TimelineConsumer {
+ public:
+  VideoRenderer();
+
+  ~VideoRenderer() override;
+
+  void Bind(InterfaceRequest<MediaRenderer> renderer_request);
+
+  // Gets an RGBA video frame corresponding to the specified reference time.
+  // |width| and |height| refer to |rgba_buffer|.
+  void GetRgbaFrame(uint8_t* rgba_buffer,
+                    size_t width,
+                    size_t height,
+                    int64_t reference_time);
+
+ private:
+  struct PacketAndCallback {
+    PacketAndCallback(MediaPacketPtr packet,
+                      const SendPacketCallback& callback);
+
+    ~PacketAndCallback();
+
+    MediaPacketPtr packet_;
+    SendPacketCallback callback_;
+  };
+
+  // MediaRenderer implementation.
+  void GetSupportedMediaTypes(
+      const GetSupportedMediaTypesCallback& callback) override;
+
+  void SetMediaType(MediaTypePtr media_type) override;
+
+  void GetConsumer(InterfaceRequest<MediaConsumer> consumer_request) override;
+
+  void GetTimelineControlSite(
+      InterfaceRequest<MediaTimelineControlSite> control_site_request) override;
+
+  // MediaConsumer implementation.
+  void SetBuffer(ScopedSharedBufferHandle buffer,
+                 const SetBufferCallback& callback) override;
+
+  void SendPacket(MediaPacketPtr packet,
+                  const SendPacketCallback& callback) override;
+
+  void Prime(const PrimeCallback& callback) override;
+
+  void Flush(const FlushCallback& callback) override;
+
+  // MediaTimelineControlSite implementation.
+  void GetStatus(uint64_t version_last_seen,
+                 const GetStatusCallback& callback) override;
+
+  void GetTimelineConsumer(
+      InterfaceRequest<TimelineConsumer> timeline_consumer_request) override;
+
+  // TimelineConsumer implementation.
+  void SetTimelineTransform(
+      int64_t subject_time,
+      uint32_t reference_delta,
+      uint32_t subject_delta,
+      int64_t effective_reference_time,
+      int64_t effective_subject_time,
+      const SetTimelineTransformCallback& callback) override;
+
+  // Clears the pending timeline function and calls its associated callback
+  // with the indicated completed status.
+  void ClearPendingTimelineFunction(bool completed);
+
+  // Apply a pending timeline change if there is one an it's due.
+  void MaybeApplyPendingTimelineChange(int64_t reference_time);
+
+  // Publishes end-of-stream as needed.
+  void MaybePublishEndOfStream();
+
+  // Sends status updates to waiting callers of GetStatus.
+  void SendStatusUpdates();
+
+  // Calls the callback with the current status.
+  void CompleteGetStatus(const GetStatusCallback& callback);
+
+  Binding<MediaRenderer> renderer_binding_;
+  Binding<MediaConsumer> consumer_binding_;
+  Binding<MediaTimelineControlSite> control_site_binding_;
+  Binding<TimelineConsumer> timeline_consumer_binding_;
+  MappedSharedBuffer shared_buffer_;
+  std::queue<PacketAndCallback> packet_queue_;
+  TimelineFunction current_timeline_function_;
+  TimelineFunction pending_timeline_function_;
+  SetTimelineTransformCallback set_timeline_transform_callback_;
+  int64_t end_of_stream_pts_ = kUnspecifiedTime;
+  bool end_of_stream_published_ = false;
+  uint64_t status_version_ = 1u;
+  std::vector<GetStatusCallback> pending_status_callbacks_;
+  VideoConverter converter_;
+};
+
+}  // namespace media
+}  // namespace moj
+
+#endif  // MOJO_SERVICES_MEDIA_COMMON_CPP_VIDEO_RENDERER_H_