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+# DRM HAL
+
+This is the underlying HAL implementation for `MediaDrm`/`MediaCrypto` (and
+their NDK counterparts).
+
+## Plugin-vendor-specific VTS modules
+
+The interface `DrmHalVTSVendorModule_V1` is compatible with all versions of the
+DRM HAL (hidl 1.0-1.4, aidl).
+
+Please see `./1.0/vts/doc/Drm_Vendor_Modules_v1.pdf`.
+
+TODO(b/266091099): convert `Drm_Vendor_Modules_v1.pdf` to Markdown.
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