Fix black video on non-Vulkan GPUs: bundle vulkan-1.dll with libmpv - #13888
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The shinchiro 20260814 libmpv (beta 17/18) carries a load-time import of vulkan-1.dll after upstream's 2026-08-04 "vulkan: disable static loader" change. That DLL is installed by GPU drivers, not Windows, so on machines with pre-Vulkan GPUs (or the Microsoft Basic Display driver) LoadLibrary fails outright: black video, no sound, waveform still fine (issue #13856, upstream shinchiro/mpv-winbuild-cmake#831). Repackaged the zips as support-files tag libmpv-2026-08-14b with the Authenticode-signed Khronos loader from the LunarG 1.4.357.0 runtime (x64 and ARM64) plus its license next to libmpv-2.dll; the libmpv DLLs are byte-identical to before. SE loads libmpv with LOAD_WITH_ALTERED_SEARCH_PATH + SetDllDirectory, so the adjacent loader is found; with zero Vulkan ICDs it no-ops and mpv's d3d11/OpenGL contexts work as before. Also copy the whole extracted zip in the Windows CI publish legs, and make the libmpv-update fallback mover carry every file in the folder instead of only libmpv-2.dll. Fixes #13856 Co-Authored-By: Claude Fable 5 <[email protected]>
Manual libmpv installs need vulkan-1.dll too: builds from August 2026 link the Vulkan loader dynamically, so libmpv-2.dll does not load at all without it. Note that in the third-party components list, and add the "black video, no sound, waveform works" symptom to the FAQ. BatchConvertStatusColor_StillFollowsTheErrorTextAfterItChanges used "is the result a brush at all" as a proxy for "is it the error brush". That proxy only held while non-error statuses returned UnsetValue - since the in-progress statuses were given the explicit theme text brush the test failed. Compare brush identity instead, which is what it was really asserting. Co-Authored-By: Claude Fable 5 <[email protected]>
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The regression
Since beta 17, users on GPUs without a Vulkan runtime get a black video with no sound (waveform still works) — reported in #13856 by a GeForce 9500 GT user, where beta 16 works fine.
The libmpv bump in #13761 (shinchiro 20260814) picked up upstream's 2026-08-04 "vulkan: disable static loader" change:
libmpv-2.dllnow has a load-time PE import ofvulkan-1.dll(both x64 and ARM64; the April DLL had none — Vulkan was statically linked).vulkan-1.dllis installed by GPU drivers, not by Windows, so on any machine whose driver predates Vulkan (or with the Microsoft Basic Display driver)LoadLibrary("libmpv-2.dll")fails outright — mpv never even initializes. Upstream ships no loader with their packages either; their open issue shinchiro/mpv-winbuild-cmake#831 says "install the LunarG runtime yourself".The repackaging in #13761 itself was clean — both DLLs verified byte-identical to upstream's non-v3 x86_64 / aarch64 archives.
The fix
New support-files release libmpv-2026-08-14b: the same libmpv DLLs (SHA256-verified unchanged) with the Authenticode-signed Khronos Vulkan loader from the LunarG 1.4.357.0 runtime (Apache-2.0, license text included) next to them — x64 loader in the x64 zip, ARM64 loader in the ARM64 zip.
This works because SE loads libmpv with
LOAD_WITH_ALTERED_SEARCH_PATH+SetDllDirectory, so the adjacentvulkan-1.dllresolves the import. On machines with no Vulkan drivers the loader simply enumerates zero ICDs and mpv's d3d11/OpenGL context probing works exactly as before; on Vulkan-capable machines nothing changes.Repo changes:
LibMpvDownloadService .cs— point both download URLs at thebtag (the in-app unpack already extracts every root-level.dll, sovulkan-1.dllflows through).build-ui.yml— point the CI download at thebtag and copy the whole extracted zip into both Windows publish folders instead of onlylibmpv-2.dll.MainViewModel.cs— thelibmpv-updatefallback (used when the old DLL is locked during an in-app update) now moves every file in the folder, not justlibmpv-2.dll.Docs
docs/third-party-components.md— manual libmpv installs need the loader too, so the MPV section now says where to getvulkan-1.dlland that SE's own download button already includes it.docs/faq.md— added the "black video, no sound, but the waveform works" symptom under Troubleshooting, since that combination is the tell-tale for libmpv failing to load.Unrelated test fix
BatchConvertStatusColor_StillFollowsTheErrorTextAfterItChangeswas failing onmainbefore this branch: #13883 and #13884 raced. The test used "is the result a brush at all" as a proxy for "is it the error brush", which only held while non-error statuses returnedUnsetValue; #13884 correctly changed those to the explicit theme text brush to fix black-on-dark status text. The test now compares brush identity, which is what it was actually asserting. All four test projects pass (3235 + 1399 + 251 + 376).Fixes #13856
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