Colour Correcting at DVinfo.net

Ken Hodson · April 2nd, 2005, 12:05 PM

From my experience the HD1/10 are a little different to CC. So I though I would start a general poll on how we go about it. Any tricks or tips or traps you would recommend?

What's your preferred method?

Do you use a chroma filter? If so which one? (eg. Algolith, Cineform,Virtuaub)

Do you upsample to a higher colour space first? Do you use a special program to do this? (Magic Bullet, Cineform ect.)

Do you stay in 8-bit or move to 10-bit colour.

Ken Hodson · April 3rd, 2005, 06:32 PM

Come-on boys! Some of you have to CC?

Graham Hickling · April 3rd, 2005, 09:04 PM

I've used the avisynth2.5 filter CNR2 with some success, but for noisy footage rather than for color correction per se.

It's here: http://ziquash.chez.tiscali.fr/

(It's essentially a YV12 & YUY2 port of the CNR filter in VDub)

I use PPro's internal cc, but Color Finesse gets good reviews:

http://www.synthetic-ap.com/products/cf/

Ken Hodson · April 3rd, 2005, 11:01 PM

Thanks Graham I am finding some very interesting stuff from your link. One question, is the YUV of HDV, YV12 like the mpeg2 of DVD's?

Graham Hickling · April 4th, 2005, 02:46 PM

Hmmm ...... HDV is 4:2:0 (like PAL DV) but which code they use for it I'm not quite sure.

Ken Hodson · April 4th, 2005, 11:20 PM

YV12 is what 4:2:0 is in HDV and DVD's, I believe. Just learning here myself.
YUY2 is 4:2:2 and is what the Cineform codec and others use. So the Avisynth filters, or most of them should work on both.
Some filters that looked promising to me are Deen (a group of filters) Fluxsmooth, NoMoSmooth and Convolution3D.

My main problem with the HD10 footage shot in non optimal studio conditions is the chroma noise. Those danged jumpy colour spots from frame to frame. This I am thinking is best suited to a temporal noise reducer. Then maybe a Spacial noise reducer to follow. It is this temporal noise that degrades the footage the most in my opinion.
How is the CNR plugin? What are its strengths and weak points?

I like the Aloglith plugins for after effects, but find they are slow and I would prefer seperate settings for temperal and spacial reductions. The Cineform chroma plugin gives no settings, and seems to have little impact on bad noise.

Graham Hickling · April 5th, 2005, 12:01 AM

Well although I've tried CNR2 ocasionally I typically use one of the other smoothers, so that I can smooth on luminace as well as chroma. After some initial comparisons I settled on "Dust" http://www.avisynth.org/warpenterprises/files/dust_20_dll_20030123.zip as the best trade-off between speed and quality.

Sadly that filter didnt get ported to Avisynth2.5, so I then started using Convolution3D which is very effective, but slower.

Most recently, I've been leaving the master footage unfiltered, and instead apply the internal smoothing filters in Procoder or TmpgEnc3XP as I encode to SD Mpeg2 for DVD - that way I always have the option of applying more or less (or better!)smoothing to the master footage at some later date.

Murad Toor · April 5th, 2005, 01:02 PM

Ken, I just leave it as is and hope nobody else notices. Just kidding.

I was wondering why I get breaks in my histogram when color correcting. Is that a matter of incomplete color information? The histogram wasn't explained in the short color correction book I have.

Applying the Anti-Alias filter fills the breaks in the histogram and adds some bumps to its contour.

I'll experiment with temporal noise reduction in my MPEG2 encoder. Graham, thanks for the idea.

I'm transcoding to DVCProHD720p from the camera's transport stream, using MPEG Streamclip, and editing in FCP.

April 2nd, 2005, 12:05 PM	#1
Ken Hodson Trustee Join Date: Aug 2003 Location: Vancouver BC Canada Posts: 1,315	Colour Correcting From my experience the HD1/10 are a little different to CC. So I though I would start a general poll on how we go about it. Any tricks or tips or traps you would recommend? What's your preferred method? Do you use a chroma filter? If so which one? (eg. Algolith, Cineform,Virtuaub) Do you upsample to a higher colour space first? Do you use a special program to do this? (Magic Bullet, Cineform ect.) Do you stay in 8-bit or move to 10-bit colour. __________________ Damnit Jim, I'm a film maker not a sysytems tech.

April 3rd, 2005, 06:32 PM	#2
Ken Hodson Trustee Join Date: Aug 2003 Location: Vancouver BC Canada Posts: 1,315	Come-on boys! Some of you have to CC? __________________ Damnit Jim, I'm a film maker not a sysytems tech.

April 3rd, 2005, 11:01 PM	#4
Ken Hodson Trustee Join Date: Aug 2003 Location: Vancouver BC Canada Posts: 1,315	Thanks Graham I am finding some very interesting stuff from your link. One question, is the YUV of HDV, YV12 like the mpeg2 of DVD's? __________________ Damnit Jim, I'm a film maker not a sysytems tech.

April 4th, 2005, 11:20 PM	#6
Ken Hodson Trustee Join Date: Aug 2003 Location: Vancouver BC Canada Posts: 1,315	YV12 is what 4:2:0 is in HDV and DVD's, I believe. Just learning here myself. YUY2 is 4:2:2 and is what the Cineform codec and others use. So the Avisynth filters, or most of them should work on both. Some filters that looked promising to me are Deen (a group of filters) Fluxsmooth, NoMoSmooth and Convolution3D. My main problem with the HD10 footage shot in non optimal studio conditions is the chroma noise. Those danged jumpy colour spots from frame to frame. This I am thinking is best suited to a temporal noise reducer. Then maybe a Spacial noise reducer to follow. It is this temporal noise that degrades the footage the most in my opinion. How is the CNR plugin? What are its strengths and weak points? I like the Aloglith plugins for after effects, but find they are slow and I would prefer seperate settings for temperal and spacial reductions. The Cineform chroma plugin gives no settings, and seems to have little impact on bad noise. __________________ Damnit Jim, I'm a film maker not a sysytems tech.

April 3rd, 2005, 09:04 PM	#3
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,669	I've used the avisynth2.5 filter CNR2 with some success, but for noisy footage rather than for color correction per se. It's here: http://ziquash.chez.tiscali.fr/ (It's essentially a YV12 & YUY2 port of the CNR filter in VDub) I use PPro's internal cc, but Color Finesse gets good reviews: http://www.synthetic-ap.com/products/cf/

April 4th, 2005, 02:46 PM	#5
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,669	Hmmm ...... HDV is 4:2:0 (like PAL DV) but which code they use for it I'm not quite sure.

April 5th, 2005, 12:01 AM	#7
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,669	Well although I've tried CNR2 ocasionally I typically use one of the other smoothers, so that I can smooth on luminace as well as chroma. After some initial comparisons I settled on "Dust" http://www.avisynth.org/warpenterprises/files/dust_20_dll_20030123.zip as the best trade-off between speed and quality. Sadly that filter didnt get ported to Avisynth2.5, so I then started using Convolution3D which is very effective, but slower. Most recently, I've been leaving the master footage unfiltered, and instead apply the internal smoothing filters in Procoder or TmpgEnc3XP as I encode to SD Mpeg2 for DVD - that way I always have the option of applying more or less (or better!)smoothing to the master footage at some later date.

April 5th, 2005, 01:02 PM	#8
Murad Toor Regular Crew Join Date: Oct 2003 Location: Chicago, IL Posts: 125	Ken, I just leave it as is and hope nobody else notices. Just kidding. I was wondering why I get breaks in my histogram when color correcting. Is that a matter of incomplete color information? The histogram wasn't explained in the short color correction book I have. Applying the Anti-Alias filter fills the breaks in the histogram and adds some bumps to its contour. I'll experiment with temporal noise reduction in my MPEG2 encoder. Graham, thanks for the idea. I'm transcoding to DVCProHD720p from the camera's transport stream, using MPEG Streamclip, and editing in FCP.