[PATCH 1/2] mshtmlmedia: Add dll.

[Brendan Shanks]

> On Apr 21, 2022, at 10:40 PM, Mohamad Al-Jaf <mohamadaljaf at gmail.com> wrote:
> 
> On Fri, Apr 22, 2022 at 12:55 AM Nikolay Sivov <nsivov at codeweavers.com> wrote:
>> Do you see it being loaded at all? It's not always compiled in, and I don't immediately see if ENABLE_DX11_FOR_WIN7 is set anywhere.
> 
> Not on the latest versions but it's possible it was used in previous
> versions. I don't know where ENABLE_DX11_FOR_WIN7 is set, perhaps it's
> done internally at runtime after it checks the system? Seems odd for
> deadcode to exist in a project that's heavily reviewed and I really
> doubt this is the case.

It actually does look like that’s the case and it’s never enabled, it was left in the Chromium source as a TODO 7 years ago (with no action since and likely none coming):

“
Sadly the hack to get DX11 decoding to work on Windows 7 does not work. We can
get a pointer to the MFCreateDXGIDeviceManager function and the device creation
works. However the IMFTransform we use for color space conversion
does not exist on Windows 7. There is a color converter DMO which technically
could work. However it needs the video samples to expose functioning IMF2DBuffer
interfaces which is not the case sadly.

I left the code to get the pointer to the MFCreateDXGIDeviceManager function
under an ifdef for Windows 7. I will look into this at a later point in time.
"

https://codereview.chromium.org/922003002/#msg12

Brendan