Weird color flicker while playing dshow device

[ninbura]

I'm getting this weird flickering in VLC player 3.0.11 when playing a dshow device (Elgato HD60 Pro), at 54 seconds in the following video you will see the flicker:
https://www.youtube.com/watch?v=p7VqV-G ... e=youtu.be

Here are the parameters I'm using to open / play the device, launched via a PowerShell script:

Code: Select all

vlc ` dshow:// ` :dshow-vdev="Game Capture HD60 Pro (Video) (#01)" ` :dshow-adev="Game Capture HD60 Pro (Audio) (#01)" ` :dshow-size="1920x1080" ` :dshow-aspect-ratio=16\:9 ` :dshow-chroma= ` :dshow-fps=60 ` :no-dshow-config ` :no-dshow-tuner ` :dshow-tuner-channel=0 ` :dshow-tuner-frequency=0 ` :dshow-tuner-country=0 ` :dshow-tuner-standard=0 ` :dshow-tuner-input=0 ` :dshow-video-input=-1 ` :dshow-video-output=-1 ` :dshow-audio-input=-1 ` :dshow-audio-output=-1 ` :dshow-amtuner-mode=1 ` :dshow-audio-channels=0 ` :dshow-audio-samplerate=48000 ` :dshow-audio-bitspersample=16 ` :live-caching=300 ` --aout=waveout ` --waveout-audio-device="Realtek Digital Output (2- Real (`$1,`$64)"

And here is the resulting logfile from the above video:
https://drive.google.com/file/d/1anN-O0 ... sp=sharing

Not sure what I should be looking for... any ideas?

[Hitchhiker]

I played the video in the same version, but don't see any flickering.

In preferences, Input / Codecs menu disable "Hardware-accelerated decoding" at the top. Save, exit and restart vlc.

[ninbura]

I played the video in the same version, but don't see any flickering.

In preferences, Input / Codecs menu disable "Hardware-accelerated decoding" at the top. Save, exit and restart vlc.

Sorry? I'm a bit confused, you don't need to play the video in VLC to see the flicker it's baked into the file at this point, to get the video I just screen recorded VLC while playing the dshow device. I can't give you the exact frame but it happens between 54 and 55 seconds, it can be seen in the YouTube video I posted and locally if you were to download the file:


I tried disabling Hardware-Accelerated Decoding and it did not help, not to mention it negatively affects performance.

[Hitchhiker]

After downloading the video and using the frame-by-frame option ('e' key) to move forward from 54 secs the font color changes briefly from blue to orange and back to blue again.


(click to enlarge)



There's no other discernible event other than that one as far as I can tell. Maybe it's intentional?

[ninbura]

After downloading the video and using the frame-by-frame option ('e' key) to move forward from 54 secs the font color changes briefly from blue to orange and back to blue again.


(click to enlarge)



There's no other discernible event other than that one as far as I can tell. Maybe it's intentional?

That's the event that I'm talking about, let me make sure I describe the situation adequately.

I'm using VLC to play a dshow device so that I can stream VLC to Discord, this adds pseudo capture card support to Discord Live. The problem is that every few minutes the dshow device while playing in VLC will flash inverted colors like is shown in the video and screenshots above, this reflects in the Discord stream which is capturing VLC. To demonstrate that this was happening in VLC I screen captured a Display with VLC open on it playing said dshow device.

When I use the exact same capture card, with the exact same source in OBS or FFmpeg with essentially identical settings (Color space, resolution, framerate) these flickers of inverse colors do not happen. As far as I can tell it is only a problem in VLC, and I feel like there is something I can probably add to my VLC command line to prevent it.

[Hitchhiker]

See if this helps: https://github.com/Pigpog/vlc-discord-rpc

[ninbura]

See if this helps: https://github.com/Pigpog/vlc-discord-rpc

Thanks for the suggestion, this is actually really cool and I will probably continue to use it in the future.

That being said it didn't fix my issue, and that's because the problem doesn't suddenly appear only when I'm streaming to Discord, but just when I play a dshow device in VLC player.

When I play the same device via dshow in FFplay, FFmpeg, OBS there are no problems. I'm quite confident that it can be resolved with some sort of parameter seeing as other applications using the exact same protocol do not exhibit the same issue.

[Hitchhiker]

The DirectShow documentation can be seen here: https://wiki.videolan.org/Documentation:Modules/dshow/

Also in the vlc Advanced settings (accessible from within the Capture Device menu) there are a number of video standards which might play a role in the issue i.e. whether the standard is NTSC, PAL or SECAM. You can change the settings in that menu. Maybe the frame rate has a bearing as well.

However, I'm not familiar with Discord I'm afraid and will have to play around with it to see if I can reproduce the problem using their tutorial.

[ninbura]

I really appreciate you taking the time to try and help, and I hope I never come off as rude or condescending.

The problem is not discord in the above video and screenshots you pulled and everything isn't being run through Discord as it stands. Maybe I should never have mentioned Discord and the only reason I did was because I was trying to explain my complete use case.

That being said, the problem is occurring with vanilla VLC 3.0.11 not running through Discord, just playing a dshow device with the aforementioned parameters.

[Hitchhiker]

Oh...OK. I misunderstood you then.

If you can't fix it by adjusting the advanced settings I mentioned you can file it as a bug at https://trac.videolan.org/vlc/