AVDRoomJoinDelegate Protocol Reference Conforms to NSObject Declared in AVDRoom.h Overview < 值类型为MediaCodecInfo.CodecCapabilities中的枚举值, 字符类型为枚举值的字符串,目前支持一下:"19" - YUV420Planar or “21” - YUV420SemiPlanar:表示房间中合屏数据回调的格式。缺省为 “19”