text: /*
   *  Copyright (c) 2018 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.
   */
  #ifndef MODULES_RTP_RTCP_SOURCE_RTP_GENERIC_FRAME_DESCRIPTOR_H_
  #define MODULES_RTP_RTCP_SOURCE_RTP_GENERIC_FRAME_DESCRIPTOR_H_
  
  #include <stddef.h>
  #include <stdint.h>
  
  #include <vector>
  
  #include "absl/types/optional.h"
  #include "api/array_view.h"
  
  namespace webrtc {
  
  class RtpGenericFrameDescriptorExtension;
  
  // Data to put on the wire for FrameDescriptor rtp header extension.
  class RtpGenericFrameDescriptor {
   public:
    static constexpr int kMaxNumFrameDependencies = 8;
    static constexpr int kMaxTemporalLayers = 8;
    static constexpr int kMaxSpatialLayers = 8;
  
    RtpGenericFrameDescriptor();
    RtpGenericFrameDescriptor(const RtpGenericFrameDescriptor&);
    ~RtpGenericFrameDescriptor();
  
    bool FirstPacketInSubFrame() const { return beginning_of_subframe_; }
    void SetFirstPacketInSubFrame(bool first) { beginning_of_subframe_ = first; }
    bool LastPacketInSubFrame() const { return end_of_subframe_; }
    void SetLastPacketInSubFrame(bool last) { end_of_subframe_ = last; }
  
    // Properties below undefined if !FirstPacketInSubFrame()
    // Valid range for temporal layer: [0, 7]
    int TemporalLayer() const;
    void SetTemporalLayer(int temporal_layer);
  
    // Frame might by used, possible indirectly, for spatial layer sid iff
    // (bitmask & (1 << sid)) != 0
    int SpatialLayer() const;
    uint8_t SpatialLayersBitmask() const;
    void SetSpatialLayersBitmask(uint8_t spatial_layers);
  
    int Width() const { return width_; }
    int Height() const { return height_; }
    void SetResolution(int width, int height);
  
    uint16_t FrameId() const;
    void SetFrameId(uint16_t frame_id);
  
    rtc::ArrayView<const uint16_t> FrameDependenciesDiffs() const;
    void ClearFrameDependencies() { num_frame_deps_ = 0; }
    // Returns false on failure, i.e. number of dependencies is too large.
    bool AddFrameDependencyDiff(uint16_t fdiff);
  
   private:
    bool beginning_of_subframe_ = false;
    bool end_of_subframe_ = false;
  
    uint16_t frame_id_ = 0;
    uint8_t spatial_layers_ = 1;
    uint8_t temporal_layer_ = 0;
    size_t num_frame_deps_ = 0;
    uint16_t frame_deps_id_diffs_[kMaxNumFrameDependencies];
    int width_ = 0;
    int height_ = 0;
  };
  
  }  // namespace webrtc
  
  #endif  // MODULES_RTP_RTCP_SOURCE_RTP_GENERIC_FRAME_DESCRIPTOR_H_
  