Miracast学习（一）-- Message

Miracast是Wi-Fi Alliance于2012年9月19日宣布启动的Wi-Fi CERTIFIED Miracast™认证项目。Miracast设备提供简化发现和设置，用户能够迅速在设备间传输视频。

miracast里面source 发起， 一共有消息以下：

M1： source -> sink

命令：Option

询问Sink端服务能力, 给sink设置Option的trigger

M2：sink->source

命令：Option

受Source 唤起，询问Source 端服务能力

M3：source -> sink

命令：Get_Parameter

询问sink端参数

M4：source -> sink

命令：Set_Parameter

设置sink端参数

M5：source -> sink

命令：setup

初始化sink端，给sink设置setup的trigger

M6：sink-> source

命令：setup

初始化source端

M7/8/9/10：sink -> source

命令：PLAY/TEARDOWN/PAUSE

sink控制rtsp流命令，除了play在创建链接时候自动运行以外，其余等待source的M5 trigger。

M10：sink-> source

命令：SET_PARAMETER

切换主辅sink

M11：sink-> source

命令：SET_PARAMETER

更改connection type

M12：source-> sink

命令：SET_PARAMETER

更改standby 模式

M13：sink-> source

命令：SET_PARAMETER

要求 IDR picture

M14：source-> sink

命令：SET_PARAMETER

创建UIBC

M15：source-> sink； sink-> source

命令：SET_PARAMETER

开关UIBC

M16：source-> sink

命令：Get_PARAMETER

rtsp对话存活性测试

Id	Requester	Payload	Behavior	Description	RTSP State
M1	WFD source	6.2.1	6.4.1	Query sink options	Init
M2	WFD sink	6.2.1	6.4.2	Query source options	Init
M3	WFD source	6.1.2-6.1.7, 6.1.10	6.4.3	Query sink capabilities	Init (for WFD Capability Negotiation) Playing (for WFD Capability Re-negotiation)
M4	WFD source	6.1.2-6.1.7	6.4.4	Set sink parameters	Init (for WFD Capability Negotiation) Playing (for WFD capability Re-negotiation)
M5	WFD source	6.1.8	6.4.5	Trigger WFD sink to issue {SETUP|PLAY|TEARDOWN|PAUSE}   request.	Init (for SETUP) Playing (for PAUSE, PLAY at “PAUSE”   sub-state, and TEARDOWN)
M6	WFD sink	6.2.4	6.4.6	Send SETUP request to WFD source.	Ready
M7	WFD sink		6.4.7	Send PLAY request to WFD source.  WFD source begins audio and/or video streaming.	Ready (for initiate streaming) Playing (at “PAUSE” sub-state)
M8	WFD sink		6.4.8	Send TEARDOWN request to WFD source	Playing
M9	WFD sink		6.4.9	Send PAUSE request to WFD source. WFD   source pauses the audio video stream(s)	Playing
M10	WFD sink	6.1.11	6.4.10	Send RTSP SET_PARAMETER with wfd-route to   change the sink at which audio is rendered. Applies only when both a Primary   and a Secondary sinks are in WFD Session with a WFD source.	Playing (optional)
M11	WFD   sink	6.1.19	6.4.11	Send   RTSP SET_PARAMETER with wfd-connector-type to indicate change of active   connector type, when the WFD source and the WFD sink support content   protection.	Playing   (optional)
M12	WFD   source WFD   sink	6.1.18	6.4.12	Send   RTSP SET_PARAMETER with wfd-standby to indicate that the sender is entering ‘standby’   mode.	Playing   (optional)
M13	WFD   sink	6.1.20	6.4.13	Send   RTSP SET_PARAMETER with wfd-idr-request to request IDR refresh	Playing (optional   at the Primary sink to send request, and mandatory at the WFD source to   respond)
M14	WFD   source WFD   sink	6.1.15	6.4.14	Send   RTSP SET_PARAMETER with wfd-uibc-capability to select UIBC to be used.	Playing (optional)
M15	WFD   source WFD   sink	6.1.16	6.4.15	Send   RTSP SET_PARAMETER with wfd-uibc-setting to enable/disable UIBC.	Playing (optional)
M16	WFD   source		6.4.16	Send   GET_PARAMETER to confirm active RTSP session	Ready Playing