Need help with color correction

[Die Kuh macht Muh]

I'm trying to fix colors, brightness etc on a video before encoding it. I used the Tweak filter to alter brightness, contrast and saturation after which the picture looks better (I think).
However, a lot of things still look kind of purple. Look at the roof and the guy's face. I already experimented with the hue setting, but all it did was turn things green.

So my question is, can anyone tell me what filter I would use to fix the purpleness?

Here's the before and after pictures:

Before:
http://img371.imageshack.us/img371/2264/mannohnetweakeb9.png

After:
http://img469.imageshack.us/img469/3576/mannbright10cont115sat1ab6.png

Before:
http://img371.imageshack.us/img371/8404/dachohnetweakpm6.png

After:
http://img371.imageshack.us/img371/378/dachbright10cont115sat1ne1.png

[Pookie]

RemovePurple() :D just kidding


You can try a strong chroma cleaner

fft3dfilter(plane=3,sigma=4,degrid=1)

tweak sigma to taste.

[rfmmars]

I have alot of this problem in my Video-Film transfer business.

Using "Fdump's" Colormill 2.1 and EQrgb 2.11 plugins, this can be corrected. These are VD plug-ins which can be called in a AVS script or applied on a frame by frame basis using Magix's EP-11 Plus UK version or the German VideoDeluxe2007 Plus or VideoDeluxe2006-2007 Plus NLE programs. VD plug-ins can't be called in any Magix US version.

Richard
photorecall.net

[Mug Funky]

in theory RGBlut should get you most of the way there. then maybe a hue/sat (hue shouldn't be touched unless things are really off... there's no colourbars on your source is there?)

[videoFred]

RemovePurple() :D just kidding.

FixVideo() :p (with standard settings)

Fred.

[Die Kuh macht Muh]

I have alot of this problem in my Video-Film transfer business.

Using "Fdump's" Colormill 2.1 and EQrgb 2.11 plugins, this can be corrected. These are VD plug-ins which can be called in a AVS script or applied on a frame by frame basis using Magix's EP-11 Plus UK version or the German VideoDeluxe2007 Plus or VideoDeluxe2006-2007 Plus NLE programs. VD plug-ins can't be called in any Magix US version.

Richard
photorecall.net
Thank you. I tried both Color Mill and EQRBG. EQRGB has more settings and I was able to get slightly better results with it than with Color Mill.
Still, I have to say I am not impressed with the picture so far. The purple tint isn't nearly as bad as it was before, but it is still there. Also, it seems I traded the purple tint for a slight greenish to yellowish look in some parts. This is especially visible in black and white scenes (see pictures below).

I found two VirtualDub filters, though: Color Equalizer and Gradation Curve. I'll play with those when I have time.
Here are the EQRGB results:

Before:
http://img356.imageshack.us/img356/3131/dachvorherlu1.png

After:
http://img378.imageshack.us/img378/681/dachnachhergd7.png

Before:
http://img378.imageshack.us/img378/8188/mannvorherik6.png

After:
http://img378.imageshack.us/img378/8698/mannnachheran5.png

Before:
http://img378.imageshack.us/img378/8080/swvorherkb8.png

After:
http://img460.imageshack.us/img460/847/swnachherzk9.png

For comparison, a grayscale version (ideally, this is what the picture would look like after the color correction):
http://img356.imageshack.us/img356/8931/swgraustufenba6.png

[Die Kuh macht Muh]

in theory RGBlut should get you most of the way there. then maybe a hue/sat (hue shouldn't be touched unless things are really off... there's no colourbars on your source is there?)
Fortunately, no. But the color distortion isn't a simple hue shift or anything one-dimensional like that. If it was, playing with the hue setting would have fixed it (right?)

[Die Kuh macht Muh]

FixVideo() :p (with standard settings)

Fred.

Thanks, I'll do that.

[rfmmars]

Fortunately, no. But the color distortion isn't a simple hue shift or anything one-dimensional like that. If it was, playing with the hue setting would have fixed it (right?)


You want to have the EQrgb load first and want to adjust so the picture has a slight green tint in the face, using white balance and hue. Don't forget the many lum choices at the top right corner. Then follow up with Colormill Simular "NOT HSV button" mode second left from top, DO NOT USE REAL. Pull the s-HSV Hue downward just a little until max color sat & flesh tone is reached. You may want now to reduce the total color sat at this point with the slider to the right. This is a non linera function to correct this distortion. You will end up with good fresh but weak green, so that's why you add some green with EQrgb.

Keep going back and foreth until you are satified. Billions of combinations.

Richard

[superuser]

have u tried hdragc? if not try it out in addition to saturation and brightness (gain), its black clip parameter with appropriate values for shift u and v will also help.

[Die Kuh macht Muh]

You want to have the EQrgb load first and want to adjust so the picture has a slight green tint in the face, using white balance and hue. Don't forget the many lum choices at the top right corner. Then follow up with Colormill Simular "NOT HSV button" mode second left from top, DO NOT USE REAL. Pull the s-HSV Hue downward just a little until max color sat & flesh tone is reached. You may want now to reduce the total color sat at this point with the slider to the right. This is a non linera function to correct this distortion. You will end up with good fresh but weak green, so that's why you add some green with EQrgb.

Keep going back and foreth until you are satified. Billions of combinations.

Richard
Thank you so much. I followed your advice and the colors, if not perfect, look a lot better now.
I guess there is always a trade-off between green and purple. By making the flesh tones look right you always distort the green on trees into something blueish, and vice versa. Or maybe I just needed to tinker with the settings some more.

Below are some images, in case anybody is interested. Left is before filtering, right is after.

http://img206.imageshack.us/img206/6662/baumgf9.jpg (http://img206.imageshack.us/img206/7716/baumll6.png)

http://img208.imageshack.us/img208/6982/dachgn7.jpg (http://img412.imageshack.us/img412/8449/dachck4.png)

http://img208.imageshack.us/img208/2760/mannjt9.jpg (http://img120.imageshack.us/img120/3368/mannzl3.jpg)

[Die Kuh macht Muh]

have u tried hdragc? if not try it out in addition to saturation and brightness (gain), its black clip parameter with appropriate values for shift u and v will also help.
Unless I'm mistaken, HDragc doesn't deal with color, only brightness / contrast / saturation.

[Die Kuh macht Muh]

I found a filter named TweakColor that gives better results than the combination of RGBEQ + ColorMill:

TweakColor(hue=-17,startHue=60,endHue=135)