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Stefan-3963 avatar image
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Stefan-3963 asked ElevenYu-MSFT commented

Strange Screen Resolution 1920x1280

What kind of resolution is 1920x1280?

On a 4k Laptop I can select a 1920x1280 resolution for main screen.
On a normal Laptop I can select this resolution when I extend my screen to a 4k screen.

I see this resolution also when I do miracast and when the sink uses the wfd2 protocol.
The strange thing is that the sink doesn't provide this resolution and such a resolution is not
specified in the wfd2 protocol. And windows also returns no optimal video
format in the M4 response message (wfd2-video-formats).

And now the realy strange thing. When I do miracast MICE and the laptop is connected via LAN to the
network. Windows sends a teardown after view seconds when we move the mouse over the screen...

Here the different tests I have done:

standard miracast via P2P --> no teardown
miracast MICE over WIFI interface --> no teardown
miracast MICE over LAN interface --> teardown when moving the mouse
miracast MICE over LAN interface --> no teardown when we don't move the mouse


remote-desktop-serviceswindows-10-network
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1 Answer

ElevenYu-MSFT avatar image
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ElevenYu-MSFT answered ElevenYu-MSFT commented

Hi,

Sorry I am not a specialist of Miracast. But I did some researches on both resolution 1920x1280 and Miracast.

For the resolution 1920x1280, I found a lot of people mentioned this resolution does not really exist.

If you can select it on a 4K laptop, the resolution might be 4K dedicated.


miracast MICE over LAN interface --> teardown when moving the mouse

Do you mean the resolution was lowered in this scenario?

I can only find below article that might have something related to this.
https://docs.microsoft.com/en-us/windows-hardware/design/device-experiences/wireless-projection-receiver-manufacturers#stream-enhancements

It mentioned a Miracast-specific feature Stream enhancements. In order to produce better stream quality, the Miracast Source can Dynamically switch the resolution and frame rate. I am not sure if moving the mouse will trigger the change of the resolution.

Hope the above information could give you some helps.

Thanks,


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Hi ElevenYu-MSFT,

yes 1920x1280 is not really a common resolution.
yes I selected this resolution for the 2nd monitor on my 4k Notebook.
But you will see it also on FullHD Notebooks when you make a miracast connection
to a 4k Miracast device. So this is not really a 4k Notebook issue.

The dynamic resolution switch without a RTSP message is no problem for gstreamer
and is handled there correct.

Windows doesn't do a resolution switch of the video stream it sends the RTSP TEARDOWN message
to the sink and is therefore actively stopping the miracast connection!

So Windows is doing two more things not correct. It provides a strange resolution of 1920x1280 and
after the the connection is established it stops the miracast connection automatically after view
seconds. Maybe windows recognize that it is using a wrong resolution. I don't know.
And that you can see this shutdown only via miracast MICE when you make the miracast
connection over the LAN interface of the laptop.

0 Votes 0 ·

Hi,

Thank you for the further clarification.

As miracast MICE is not a support topic in Q&A forum, we suggest that you could post this issue to the Windows Community to see if there is any other expert can provide more satisfying explanation and solution to this issue.

Appreciate your understanding.

Thanks,


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