Doom9's Forum - View Single Post - KNLMeansCL: OpenCL NLMeans de-noising algorithm [2018-01-29]

SaurusX · 25th July 2017, 15:51

Well, I found a way to break the filter while encoding some cartoons. Here's the pseudo-script:

MPEG2SOURCE("myclip")
TComb(mode=0, blah, blah) #for dot-crawl removal
TFM()
TDecimate()
the masked and motion-compensating derainbowing procedure found here
Bifrost(interlaced=false) #1.1 version for final de-rainbowing
KNLMeansCL(d=2,a=3,h=1.2,device_type="GPU") #Using Intel HD4000 graphics
maa2() #anti-alias
msharpen() #resharpen
dehalo_alpha() #de-halo
awarpsharp2() #sharpen chroma

It seems like too much temporal analysis will cause mask pops, frame flashing, and mistimed chroma in the final encode. I can remove TComb or remove Bifrost or change the d parameter to 1 and the problems disappear. This may not be a specific problem to KNLMeansCL, but I thought you'd like to know about it.

25th July 2017, 15:51	#1203 \| Link
SaurusX Registered User Join Date: Feb 2017 Posts: 135	Well, I found a way to break the filter while encoding some cartoons. Here's the pseudo-script: MPEG2SOURCE("myclip") TComb(mode=0, blah, blah) #for dot-crawl removal TFM() TDecimate() the masked and motion-compensating derainbowing procedure found here Bifrost(interlaced=false) #1.1 version for final de-rainbowing KNLMeansCL(d=2,a=3,h=1.2,device_type="GPU") #Using Intel HD4000 graphics maa2() #anti-alias msharpen() #resharpen dehalo_alpha() #de-halo awarpsharp2() #sharpen chroma It seems like too much temporal analysis will cause mask pops, frame flashing, and mistimed chroma in the final encode. I can remove TComb or remove Bifrost or change the d parameter to 1 and the problems disappear. This may not be a specific problem to KNLMeansCL, but I thought you'd like to know about it. Last edited by SaurusX; 25th July 2017 at 15:54.