Bug Report Red colour corruption with DirectX renderer

[FrostyCoolSlug]

I've been noticing that red colours recorded by OBS using the DirectX rendering engine seem to have an odd form of 'corruption' (for want of a better word). Areas around the reds seem to become distorted and blocky. The preview window seems to be correctly rendering the image.

Below is an image of what I'm seeing (Note the reds, especially at the top-middle of the screen, Log Here):

When switching OBS to the OpenGL renderer and the same settings, the (roughly) same image produces the correct results (Log Here):

Any idea what may be causing this? I unfortunately can't stick with the OpenGL renderer due to significantly poorer performance than the DX11 one.

Thanks.

 

[Sapiens]

https://en.wikipedia.org/wiki/Chroma_subsampling is the cause, it's normal behavior.

 

[FrostyCoolSlug]

Hi Sapiens, thanks for your response.

A couple of points just for clarification purposes:

- I am aware of some general degradation which comes from recording videos (especially in reds), but what I'm seeing here appears to be an overly extreme example.
- I only started experiencing this problem a few weeks ago after I reformatted my machine, before then these settings produced the correct results
- The only difference between the two images is the OBS setting of Settings -> Advanced -> Renderer, my encoder settings remained the same for both recordings.
- Edit, could this be AU related in some way given that it occurred after a fresh install of Windows 10 and I run an Nvidia card?

I'm curious as to why the OBS Direct3D 11 Renderer seems to massively exacerbate this problem, where as the OpenGL one doesn't have any problems at all. If I was changing the encoder between between recordings, then it would make sense that there would be differences in behaviour, but I'm not, it's just the one OBS specific setting that I'm changing.

I've included some a more 'centralised example' at a size that fits better to the forums, so you can evaluate how bad this is (note that the recordings were made at 1440p, the images aren't scaled up). Note that both of these images are screenshots of an OBS recording.


File -> Setting -> Advanced -> Renderer -> Direct3D 11

File -> Settings -> Advanced -> Renderer -> OpenGL

Hopefully you can help clear this up for me.

Thanks.

 

[FrostyCoolSlug]

Additional info, I've done some more testing and uploaded a 'test clip' to youtube here (apologies for quality, best I could do with youtube).

From what I can tell, there are persistent vertical lines going down the entire recording that are offsetting reds by a few pixels at each of the boundaries.

Not really sure what else I can do for testing here..

 

[FrostyCoolSlug]

Final Note, I've just tried dropping my screen resolution from 1440p down to 1080p and performing a recording and the problem seems to go away. So it's possibly related to high resolutions when using the Direct3D 11 backend.

Cheers.