WLXCodecHost.exe

Source	src/WLXCodecHost/
CMake target	WLXCodecHost
Type	Win32 EXE (~32 KB / ~20 KB code in the original)
Family	Media Foundation targets

At a glance

An out-of-process COM codec host: hosts media codecs in a surrogate process so a misbehaving third-party codec cannot take down the editor. The reference binary exposes the 4 COM standard entries and nothing else — no RTTI classes (pure host shell).

Role

COM activation (via CoCreateInstance with CLSCTX_LOCAL_SERVER) hands codec work to this process. MovieMakerCore's WLXCodecHostPS proxy/stub pair (analysis/WLXCodecHostPS/) marshals the interfaces across the process boundary.

Implementation notes

• Minimal by design: a message loop plus COM registration — the original has no application UI and no exports beyond the COM quartet.
• The reconstruction is a single source file (WLXCodecHost.cpp) implementing the local-server registration and class factory.

Testing

• tests/WLXCodecHost/ and tests/WLXCodecHostPS/ — per-module test directories.
• Built in the CI matrix.

Analysis artifacts

analysis/WLXCodecHost/ and analysis/WLXCodecHostPS/ (proxy/stub marshaling analysis).