DIAL: DIscovery And Launch简介

Posted 2020-11-25 jebediahkerman

运行以下VBScript脚本

Dim deviceFinder
Set deviceFinder = CreateObject("UPnP.UPnPDeviceFinder")
Dim devices
Set devices = deviceFinder.FindByType("ssdp:all", 0)
For Each device In devices
    WScript.Echo device.FriendlyName + " " + device.Type
Next

可以得到类似下面的结果

[TV] Samsung 6 Series (55) urn:schemas-upnp-org:device:MediaRenderer:1
[TV] Samsung 6 Series (55) urn:samsung.com:device:RemoteControlReceiver:1
[TV] Samsung 6 Series (55) urn:samsung.com:device:RemoteControlReceiver:1
[TV] Samsung 6 Series (55) urn:dial-multiscreen-org:device:dialreceiver:1
[TV] Samsung 6 Series (55) urn:dial-multiscreen-org:device:dialreceiver:1
[TV] Samsung 6 Series (55) urn:samsung.com:device:RemoteControlReceiver:1
[TV] Samsung 6 Series (55) urn:dial-multiscreen-org:device:dialreceiver:1
[TV] Samsung 6 Series (55) urn:samsung.com:device:RemoteControlReceiver:1
[TV] Samsung 6 Series (55) urn:schemas-upnp-org:device:MediaRenderer:1
[TV] Samsung 6 Series (55) urn:schemas-upnp-org:device:MediaRenderer:1
[TV] Samsung 6 Series (55) urn:schemas-upnp-org:device:MediaRenderer:1
[TV] Samsung 6 Series (55) urn:dial-multiscreen-org:device:dialreceiver:1
[TV] Samsung 6 Series (55) urn:schemas-upnp-org:device:MediaRenderer:1
[TV] Samsung 6 Series (55) urn:schemas-upnp-org:device:MediaRenderer:1
[TV] Samsung 6 Series (55) urn:schemas-upnp-org:device:MediaRenderer:1

其中有三种协议，分别是UPnP、DIAL和urn:samsung.com。UPnP是一个通用的智能设备通信协议，关于在Windows上查找UPnP设备可以参考https://www.cnblogs.com/JebediahKerman/p/Windows_UPnP_APIs.html。DIAL和urn:samsung.com都属于UPnP协议。urn:samsung.com是三星的协议，不作更多讨论。DIAL是一个通用的多屏互动协议，手机视频投送到电视上一般使用的是这个协议。关于DIAL的介绍可以在http://www.dial-multiscreen.org/找到。

注意到上面重复了四次"[TV] Samsung 6 Series (55) urn:dial-multiscreen-org:device:dialreceiver:1"，这并不是四个设备，而是同一个设备实现了DIAL的四个版本，分别是1.7、2.0、2.1和2.2。关于协议的描述可以在http://www.dial-multiscreen.org/dial-protocol-specification找到。