[1808:1844:0217/143154.096626:VERBOSE1:cast_message_handler.cc(454)] SendCastMessageToSocket: channel_id: 6, message: {source_id: sender-[sender], destination_id: [dest], namespace: urn:x-cast:com.google.cast.webrtc, payload_utf8: {"offer":{"castMode":"mirroring","receiverGetStatus":true,"supportedStreams":[{"aesIvMask":"[mask]","aesKey":"[key]","bitRate":102000,"channels":2,"codecName":"opus","index":0,"receiverRtcpEventLog":true,"rtpExtensions":"adaptive_playout_delay","rtpPayloadType":127,"rtpProfile":"cast","sampleRate":48000,"ssrc":105618,"targetDelay":400,"timeBase":"1/48000","type":"audio_source"},{"aesIvMask":"[mask]","aesKey":"[key]","codecName":"vp8","index":1,"maxBitRate":5000000,"maxFrameRate":"30000/1000","receiverRtcpEventLog":true,"renderMode":"video","resolutions":[{"height":1080,"width":1920}],"rtpExtensions":"adaptive_playout_delay","rtpPayloadType":96,"rtpProfile":"cast","ssrc":584923,"targetDelay":400,"timeBase":"1/90000","type":"video_source"}]},"seqNum":827941470,"type":"OFFER"}}