Question / Help Washed out colours

gogonono

New Member
Hi guys,

I have a rather odd problem with colours in a new streaming setup. The problem seems to be specific to one computer and not another. The specifics are as follows:

Main PC - GTX 670 Dual link DVI to montior, HDMI to Avermedia Extremecap U3
Streaming PC - Radeon 5850 HDMI to TV, Avermedia Extremecap U3 connects via USB

The settings in OBS, as far as I can make out, are identical, however the Streaming PC seems to receive very washed out colours. I assumed that might be a quirk of the capture device but it seems to not be the case, as when testing it on the main PC directly to troubleshoot a separate problem, the colour representation was fine. I have included a picture to illustrate the issue. Both screenshots were taken on the main PC via a VLC snapshot.

2i8NQJL.png

http://i.imgur.com/2i8NQJL.png

The top Image is with the Extremecap U3 connected directly to the main PC and recorded through OBS, and the bottom is the Extremecap U3 on the streaming PC, also recording through OBS, however the problem is identical through REcentral. The streaming PC was initially using the on-board HD4600 Intel graphics, but is now using an old 5850 and produces the same problem.

If anyone has any idea why this is happening, and hopefully some suggestions on how to fix it I would be extremely grateful.
 

Lain

Forum Admin
Lain
Forum Moderator
Developer
It's mostly YUV <-> RGB color conversion, combined with YUV full range and partial range issues. In the future these will be fully adjustable, but right now they are difficult to modify.

See you're capturing with a capture device, so thats YUV -> RGB. Which may or may not be accounting for range depending on the card (can vary from card to card). Then, after compositing, OBS converts again, RGB -> YUV. Also, your video player is a factor.

Do me a factor and run OBS on the target OBS, use monitor capture, and output to file and check, and if that matches instead, then we'll know it's caused by the capture card or not.
 

gogonono

New Member
Thanks for the reply, Jim. I've been struggling with this for the past couple of days but have come to the conclusion that it is probably the capture device.

I plugged the capture device directly into this computer and set up two sources, one for monitor capture like you said and one for the capture device. When switching sources in the same video, the colours visibly dulled when switching away from monitor capture.

I have discovered the same washed out colours appear in the RECentral software bundled with the device, and have since used the direct show feature in VLC to view the device directly which is also washed out.

The specification for the Extremecap claims YUV 4:2:2 for capture, but you did mention range, which with the greyish whites and dark grey blacks I get, I would assume is the issue. Alternatively, could a fault in the capture hardware be causing this?

I understand the issue doesn't seem to be OBS based, but is the range defined by hardware, or is it driver based?

I had assumed (probably wrongly) that a capture card should capture colours faithfully. In actuality, is this not the case?
 

gogonono

New Member
Ok, so I think we have gotten to the bottom of it. Despite the Nvidia control panel claiming that it was outputting full range, it evidently was a lie. It turns out this is a fairly well documented issue with the Nvidia drivers and HDMI. The DVI was fine, but the HDMI incredibly washed out.

I'm not sure of your policy on linking here, so feel free to remove it, but the following tool seems to have been a complete remedy:

http://blog.metaclassofnil.com/?p=83

The whites and blacks through the HDMI are now as near as my eyes can tell, identical, to the monitor capture, with very slight differences in the reds/blues which are so minimal I'm willing to ignore.

I'll resist my urge to edit my previous posts in an attempt to save face, as they may give someone a chuckle at my many fruitless theories, but also so anyone who is blindly googling symptoms such as myself, may stumble across this solution.

Big thanks to Jim who pretty much solved it by mentioning the color range seemingly being the issue, was only a short few clicks after googling that.
 

rizl4

New Member
jim I'm getting the same with aver media portable xsplit does not look washed out and looks more sharp any ideas
 
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