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-Vit- · 6th December 2011, 21:46

That's a messed up source. The last shot is progressive and needs no deinterlacing. The first shot looks interlaced, and the top fields are fine, but the bottom fields are just a blend of the current and next frames (i.e. they do not contain a new temporal frame). I think the middle shot (from which your screen cap is taken) is the same. Then there's that fairly strong noise, over a detailed image.

You're not going to get double rate out of this, so QTGMC may not be the correct approach, although it does even out the differences in the fields - you'll want a SelectEven afterwards.

The frame blending means the noise has a temporal echo, which may fool any temporal denoising into thinking it's not noise, meaning you need a stronger denoise that you would expect. A spatial denoise of sufficient strength will destroy the detail. Also the temporal processing of QTGMC is reinforcing the issue, leaving you with that fairly stable grain. Really this needs a more customized repair job, beyond the scope of QTGMC. Within the QTGMC settings you might want to set TR1=1 and TR2=0 (or 1), to reduce the temporal processing of QTGMC and stop the grain from being stabilized. That will leave you with more noise to get rid of though...

6th December 2011, 21:46	#1007 \| Link
-Vit- Registered User Join Date: Jul 2010 Posts: 448	That's a messed up source. The last shot is progressive and needs no deinterlacing. The first shot looks interlaced, and the top fields are fine, but the bottom fields are just a blend of the current and next frames (i.e. they do not contain a new temporal frame). I think the middle shot (from which your screen cap is taken) is the same. Then there's that fairly strong noise, over a detailed image. You're not going to get double rate out of this, so QTGMC may not be the correct approach, although it does even out the differences in the fields - you'll want a SelectEven afterwards. The frame blending means the noise has a temporal echo, which may fool any temporal denoising into thinking it's not noise, meaning you need a stronger denoise that you would expect. A spatial denoise of sufficient strength will destroy the detail. Also the temporal processing of QTGMC is reinforcing the issue, leaving you with that fairly stable grain. Really this needs a more customized repair job, beyond the scope of QTGMC. Within the QTGMC settings you might want to set TR1=1 and TR2=0 (or 1), to reduce the temporal processing of QTGMC and stop the grain from being stabilized. That will leave you with more noise to get rid of though... Last edited by -Vit-; 6th December 2011 at 22:01.