Mixedreality-webrtc: Unity3D + Hololens 2: Unable to load DLL 'mrwebrtc.dll': The specified module could not be found

[eshel]

When compiling a Unity3D app (v 2019.4.9f1) with the IL2CPP backend, then loading the built solution with VS2019 compiling and launching on HoloLens 2, I receive this error. The error is displayed on a small (barely visible) 'Development Console' window in the bottom-left corner of the deployed Unity3D/H2 app.

This happens with the latest version of the library (2.0.1). imported using the 'Scoped Registry' import method on unity described here. Compilation in VS2019 to the Release/ARM64 architecture.

[TheRisenPhoenix]

I had the same issue ( #574), arm64 is unfortunately not yet supported.

[Jason-Chn95]

Take a look at this blog https://blog.csdn.net/qq_42419143/article/details/108771003

[eshel]

Performing these steps allowed my project to launch on a Hololens 2:

1. In unity build settings, select UWP / ARM as build target (not ARM64, not x64).
2. In VS2019, compilation should also be done in ARM configuration (not ARM64).
3. Disabled 'Graphics Jobs' (related to multi-core rendering), was necessary.

Thanks for the references!

[eshel]

The above steps have indeed resolved the issue when attempting to run MixedReality-WebRTC on H2. However, I've hit a wall when attempting to add-in Hololens 2's Research Mode into the mix (which is the recommended way to access various CV cameras and sensors on the device).

I have raised this in an issue in their repo Hololens2ForCV#22.

Thought I'd circle back here and document this here as well.
Any thoughts on the matter will be highly appreciated!

[djee-ms]

Where did you see Research Mode was "the recommended way"?

• It's in public preview
• It's only for non-published apps
• It's for accessing extra sensors beyond camera/microphone (or accessing other feeds like depth we never really tested with this project)

[eshel]

@djee-ms We are building a non-published app, for research purposes, which requires access to these extra sensors. Did not mean to imply this is the recommended way for all apps, merely for apps working with these extra cameras and sensors.