{
  "context": "This criteria evaluates how well an engineer uses aiortc's frame rate and bitrate control capabilities to implement an adaptive video streaming system. The focus is on proper usage of VideoStreamTrack for custom video sources, RTCPeerConnection for statistics retrieval, and dynamic quality adjustment mechanisms.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "VideoStreamTrack inheritance",
      "description": "Uses aiortc.VideoStreamTrack as the base class for AdaptiveVideoTrack to create a custom video source that generates frames",
      "max_score": 15
    },
    {
      "name": "Frame timing control",
      "description": "Implements recv() method using proper timing mechanisms (asyncio.sleep or similar) to control frame rate, respecting the current FPS setting",
      "max_score": 15
    },
    {
      "name": "VideoFrame generation",
      "description": "Uses av.VideoFrame to create and return video frames from the recv() method with proper format and timestamps",
      "max_score": 10
    },
    {
      "name": "RTCPeerConnection.addTrack usage",
      "description": "Properly adds the video track to the peer connection using addTrack() method to enable video streaming",
      "max_score": 10
    },
    {
      "name": "Statistics retrieval",
      "description": "Uses RTCPeerConnection.getStats() method to retrieve connection statistics for monitoring quality",
      "max_score": 15
    },
    {
      "name": "Stats parsing",
      "description": "Correctly parses RTCStatsReport to extract relevant metrics (packetsLost, packetsSent, roundTripTime) from RTCOutboundRtpStreamStats or RTCInboundRtpStreamStats",
      "max_score": 10
    },
    {
      "name": "Frame rate adaptation",
      "description": "Dynamically adjusts frame rate by modifying the timing in the video track's frame generation loop based on quality metrics",
      "max_score": 10
    },
    {
      "name": "Bitrate control mechanism",
      "description": "Accesses the RTCRtpSender (via getSenders() or transceivers) to adjust video encoding parameters or codec settings for bitrate control",
      "max_score": 15
    }
  ]
}