[Warner306]

Banding Artifacts Explained


Blue Sky Color Banding

Wikipedia: Color banding is a problem of inaccurate color presentation in computer graphics. In 24-bit color modes, 8 bits per channel is usually considered sufficient to render images in BT.709 or sRGB. However, in some cases there is a risk of producing abrupt changes between shades of the same color. For instance, displaying natural gradients (like sunsets, dawns or clear blue skies) can show minor color bands.

Color banding is usually introduced at three stages:

• It was created during content production;
  
• It was added by the final codec due to low bitrates and/or poor encoding;
  
• It was created due inaccurate color conversions.
  

Banding caused by inaccurate color conversions can be eliminated by processing the image at a higher bit depth than the source and rounding any digital errors created by image processing at output with dithering. Other forms of color banding are inherent to the source video and can only be corrected by video processing designed to detect and correct abrupt changes in the color shades of gradients.

What Causes Banding in Digital Images?

[gotham_x]

it does not matter , is only for a file test of five minutes duration , I wanted to compare with algorithms more pushed with madVR and not I wanted to change the settings permanent for 1920x1080 ,Thanks anyway.

[TrueMorph]

Hi, after a long read I'm trying to come up with some settings for my specs, but its kinda hard to figure it out since my monitors native resolution is not 1080p but 1680x1050. I guess there would be more downscaling involved since I can't play 1080p material at native resolution. Specs are similar to your older HTPC: Core 2 Quad CPU and GTX 750 Ti. Question is should I just use the same settings as yours or should I modify acording to my native resolution? Any help or recommendation would be great, thanks.

[Warner306]

Hi, after a long read I'm trying to come up with some settings for my specs, but its kinda hard to figure it out since my monitors native resolution is not 1080p but 1680x1050. I guess there would be more downscaling involved since I can't play 1080p material at native resolution. Specs are similar to your older HTPC: Core 2 Quad CPU and GTX 750 Ti. Question is should I just use the same settings as yours or should I modify acording to my native resolution? Any help or recommendation would be great, thanks.

For upscaled sources, use NGU high under Image upscaling and everything else set to Let madVR decide. For 1080p downscaled, use the highest setting of SSIM possible under Image downscaling.

[Warner306]

Updated for madVR v0.91.5.

[DaSilva]

Thanks for updating the guide!!
I followed it yesterday for my new GTX 1060.
I just have 1 question: with my new card in graphics settings I can choose 2160p 4:4:4 8bit color and 2160p 4:2:2 10bit color.
My screen Is 10bit bit wich setting gives me the best quality?
I only watch Blu-Ray upscaled to 2160p.
Thanks in advance!

[Warner306]

Thanks for updating the guide!!
I followed it yesterday for my new GTX 1060.
I just have 1 question: with my new card in graphics settings I can choose 2160p 4:4:4 8bit color and 2160p 4:2:2 10bit color.
My screen Is 10bit bit wich setting gives me the best quality?
I only watch Blu-Ray upscaled to 2160p.
Thanks in advance!

8-bits dithered should give you the better image, but I'm not completely certain of that. madVR's dithering is very good. This avoids any color conversion by the GPU.

You can try each for yourself. If your sources are 8-bit, it would make the most sense to output in 8 bits.

[DaSilva]

Thanks, I've been playing around with the settings and when I use 23Hz I can select 4:4:4 12bit.
So I can narrow my choices down to 60Hz 4:4:4 8bit, 23Hz 4:4:4 12-bit.
Wich would you select?
As I said it's a dedicated HTPC so I'm not bothered with the low refresh rate.

[Warner306]

Thanks, I've been playing around with the settings and when I use 23Hz I can select 4:4:4 12bit.
So I can narrow my choices down to 60Hz 4:4:4 8bit, 23Hz 4:4:4 12-bit.
Wich would you select?
As I said it's a dedicated HTPC so I'm not bothered with the low refresh rate.

You might be able to get away with 30 Hz 4:4:4 at 10 bits. If not, I'd go with 4:4:4 8 bits. The UI will be very sluggish at 23 Hz.

[DaSilva]

Thanks, I will give it a try!!

[Bmn2016]

Please could somebody help me with best personal settings for MPC and MadVR (I am using gtx1080 and i7-5930k and samsung ue43ks7500). I would like to watch e.g. this torrent: http://bit.ly/2m7bwMP in best quality...

[Warner306]

Please could somebody help me with best personal settings for MPC and MadVR (I am using gtx1080 and i7-5930k and samsung ue43ks7500). I would like to watch e.g. this torrent: http://bit.ly/2m7bwMP in best quality...

Why not try the settings posted in this guide?

[Bmn2016]

I have already try, but I have a problem with scaling algorithms (chroma upscaling), because when I change settings for maximum processing (I have try this:NGU low - very high Reconstruction soft - sharp AR NNEDI3 16 - 256 neurons) the frames started to dropp more and more. How should I set algorithms please + what about display modes (madVR may switch to window) how should I set this?

[Warner306]

I have already try, but I have a problem with scaling algorithms (chroma upscaling), because when I change settings for maximum processing (I have try this:NGU low - very high Reconstruction soft - sharp AR NNEDI3 16 - 256 neurons) the frames started to dropp more and more. How should I set algorithms please + what about display modes (madVR may switch to window) how should I set this?

Set chroma upscaling to NGU low. Focus on luma quality. Start at NGU medium and work your way up if there are no dropped frames.

As for display modes, set 2160p23, 2160p24, 2160p50, 2160p59, 2160p60.

[Bmn2016]

I have already try, but I have a problem with scaling algorithms (chroma upscaling), because when I change settings for maximum processing (I have try this:NGU low - very high Reconstruction soft - sharp AR NNEDI3 16 - 256 neurons) the frames started to dropp more and more. How should I set algorithms please + what about display modes (madVR may switch to window) how should I set this?

Set chroma upscaling to NGU low. Focus on luma quality. Start at NGU medium and work your way up if there are no dropped frames.

As for display modes, set 2160p23, 2160p24, 2160p50, 2160p59, 2160p60.

Thank you very much for your advice. So right now I am using:
chroma upscaling NGU - high
image downscalling Jinc (with scale in linear light and activate anti-ringing filter lelaxed)
image upscaling Jinc (with activate anti-ringing filter)
upscaling refinement - off
Artifact removal - Debanding: Medium/High
Artifact removal - Deringing: Off
Image enhancements: sharpen edges (1.0) + AR + AB 50%
Dithering: Error Diffusion 2

Should I change something?