[Bug 55891] New: mfmediaengine - Frame server mode is implemented incorrectly

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=55891

            Bug ID: 55891
           Summary: mfmediaengine - Frame server mode is implemented
                    incorrectly
           Product: Wine
           Version: 8.20
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: mfplat
          Assignee: wine-bugs(a)winehq.org
          Reporter: besentv(a)gmail.com
      Distribution: ---

Today, Wine's implementation of media engine plays back the video stream at
full speed in frame server mode potentially skipping frames. Windows does in
fact play back the video stream at full speed as well, however it uses a custom
sink that only requests more frames from the pipeline, when OnVideoStreamTick()
was called.

The used sink is a private interface which can be created using the activate
interface with UUID 4d4dedaa-43c5-480d-9ee0-1464f9f4ff4b (CLSID_SVRActivate) .

Additionally Windows prerolls 2 frames by scrubbing at postition 0 (0 rate
playback) before actual playback in media engine is started by a call to
OnVideoStreamTick(). Even though it seems illogical, the Play() function just
generally allows OnVideoStreamTick() to start playback.

To properly implement this we seem to be (partially) blocked by the following
issues:

- No implementation of this custom Sink in Wine.
- Scrubbing at 0 rate seems to be broken at the moment.
- Need to manually copy frame data from CPU to GPU instead of just passing
Samples from the sink to the user program. To fix this, we need to detach
decoding from the media source and move it into the pipeline with decoder MFTs.
This also needs a minor rewrite of the topo resolving logic.

I wrote an extension to the effect test, which better shows the general issue,
which is available here:
https://gitlab.winehq.org/wine/wine/-/merge_requests/4379

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