Failing to initialize on linux

[steyrboy]

I've compiled libvlc.so and libvlccore.so from the 2.2.2 source, and I get this error when trying to load a project (running on linux):

[2016.04.07-03.32.42:711][ 0]LogVlcMedia:Warning: Failed to import VLC function libvlc_media_new_callbacks
[2016.04.07-03.32.42:711][ 0]LogVlcMedia:Warning: Failed to initialize libvlc

Any ideas? I'm running a fresh 4.11 (non-preview) source build.

[gmpreussner]

As mentioned in the README, you need to use libvlc 3.x.x

[steyrboy]

Thanks for the quick reply! I did try this out earlier today, and got different errors.

vlc: unknown option or missing mandatory argument --vmem-chroma' Tryvlc --help' for more information.
[2016.04.08-02.13.22:061][ 0]LogVlcMedia:Warning: Failed to create VLC instance ((null))

EDIT: Same error on both Ubuntu 15.10 and 14.04

[gmpreussner]

Can you try changing this to "RV16"?

I'm not exactly sure what the error message indicates. Maybe --vmem-chroma has been removed or replaced in the very latest versions. I'll see if I can repro it on Windows this weekend.

[gmpreussner]

I had a quick look at the VLC code. It looks like vmem-chroma is still there. Maybe your video_output module isn't loaded for some reason? Is there anything else in the log? Can you attach the whole output?

[gmpreussner]

Oh, you know what, I know what it is. It's not finding your VLC plug-in modules. The Linux build rules are not yet configured in the VlcMedia module. I haven't had time yet to work on that. There's likely stuff missing in VlcMedia.Build.cs and Vlc.cpp. The plug-in directory is configured in VlcMediaModule.cpp

The main issue is that I haven't figured out yet how to deal with VLC binaries on Linux. It is not clear what should be redistributed and how. It might be best to assume that libvlc is installed on the machine, although that may not be user friendly.

If you have any ideas, please let me know.

[steyrboy]

I've tried to hack it together on my end, but still no luck. in VlcMedia.Build.cs I added the following code:

            if (Target.Platform == UnrealTargetPlatform.Linux)
            {
                RuntimeDependencies.Add(new RuntimeDependency(Path.Combine(VlcDirectory, "libvlc.so")));
                RuntimeDependencies.Add(new RuntimeDependency(Path.Combine(VlcDirectory, "libvlc.so.5")));
                RuntimeDependencies.Add(new RuntimeDependency(Path.Combine(VlcDirectory, "libvlc.so.5.5.0")));
                RuntimeDependencies.Add(new RuntimeDependency(Path.Combine(VlcDirectory, "libvlc.so.5.5.0T")));
                RuntimeDependencies.Add(new RuntimeDependency(Path.Combine(VlcDirectory, "libvlccore.so")));
                RuntimeDependencies.Add(new RuntimeDependency(Path.Combine(VlcDirectory, "libvlccore.so.8")));
                RuntimeDependencies.Add(new RuntimeDependency(Path.Combine(VlcDirectory, "libvlccore.so.8.0.0")));
            }

and Vlc.cpp:

#if PLATFORM_LINUX
    const FString LibDir = FPaths::Combine(*VlcDir, TEXT("Linux"));

I added the executables and plugins built from VLC into the ThirdParty and ThirdParty/Linux/plugins folders in my engine source plugins folder along side the files you provide. The files do get copied over correctly during the build process. I am still stuck with the following error, with no other errors/warnings:

[2016.04.10-22.26.08:923][ 0]LogVlcMedia:Warning: Failed to create VLC instance ((null))

Before trying all of this, I built VLC form source and did a make install. The correct version of VLC is installed on the PC, but it still errors out saying the executables are missing.

[gmpreussner]

We're still trying to get Linux support done and may look into it this week.

[steyrboy]

I was able to get it working, but not in the most optimal way. I had to build VLC from source, then add symlinks to the project's binaries folder that point to the correct libs/execs in the installed directory in Linux. Ideally the correct libs/execs will be packaged with the project, but this workaround fits my needs (for now).

[djiamnot]

Thank you for the comments in #24. So, those comments and this issue got me much further, the plugin compiles, loads and seems to initialize. For the record, I resorted to compilation of vlc by hand as well.

I can now play videos, however, they are rendered wrong, as in most of the time I get screen-fulls of solid green with occasional flickering of images that actually belong to the video. I wonder if @steyrboy has experienced this kind of artifact, or anyone else for that matter. I used vlc master branch and even tried it against ffmpeg tagged n3.1.3. I tried playing mjpeg and h264 encoded videos with the same results (both in the editor in "game"). I think it's still related to this issue...

[faemir]

Using vlc-nightly from the AUR, then symlinked the files as @steyrboy mentioned got this running for me on Arch Linux. I get a green band at the bottom of the clips, regardless of format and video container. No sound is played (using the media sound wave uasset) either, with these errors logged:

[2016.10.10-22.16.03:138][177]LogVlcMedia:Warning: Possible loss of audio quality due to sample rate != 44100 Hz
[2016.10.10-22.16.03:140][177]LogALAudio:Warning: ALSoundBuffer wave 'TVclips_MediaPlayer_Sound' has an invalid decompression type 5.
[2016.10.10-22.16.03:140][177]LogALAudio:Warning: ALSoundBuffer init failed for wave 'TVclips_MediaPlayer_Sound', decompression type 5.
[2016.10.10-22.16.03:140][177]LogALAudio:Warning: Failed to initialize sound source with WaveInstance 'TVclips_MediaPlayer_Sound'.
[2016.10.10-22.16.03:141][177]LogALAudio:Warning: SampleRate 44100
[2016.10.10-22.16.03:141][177]LogALAudio:Warning: Channels 2
[2016.10.10-22.16.03:141][177]LogAudio:Warning: Failed to start sound source for TVclips_MediaPlayer_Sound