GamMac v1.10 - 15 June 2018

[johnmeyer]

Oh wow, I've got to try this filter!

I have been asked to re-transfer some early color film that may be used for broadcast, and this looks like the results are far better than I can do by hand. The ability to track color changes and make sensible adjustments is particularly intriguing. For me, color grading is the most time-consuming part of film transfer and restoration.

P.S. VideoFred, which version of the filter did you use for the tests you just posted?

[videoFred]

Oh wow, I've got to try this filter!

Yes, actualy I was waiting for a response from you because we are working with the same kind of films ;)


For me, color grading is the most time-consuming part of film transfer and restoration.

GamMac will take a lot of work out of your hands, believe me! Not only it corrects color cast, but also levels. But you will have to fine tune it sometimes as I explained above here.


P.S. VideoFred, which version of the filter did you use for the tests you just posted?

Version V1.06B1, it can be found here:
StainlessS@SendSpace (working link in StanlessS signature)

Fred.

[johnmeyer]

Thanks!!

[StainlessS]

GamMac v1.06 Beta02, See MediaFire in sig below.


GamMac(), [Gamma Machine] An extraordinary Idea by VideoFred (the gent from Gent). Coded by StainlessS.

Home Thread:- http://forum.doom9.org/showthread.php?p=1774281#post1774281
Idea:- http://forum.doom9.org/showthread.php?t=173683

RGB Only.

Useful to correct color cast on old 8mm films.
Alters channel pixel average to match LockChan using Gamma correction. (By default alters Red and Blue channels to match Green).
Additional tweaking via RedMul, GrnMul and BluMul multipliers.

What it does(roughly):-
Gets Channel averages, minimums, and maximums (using loTh for minumums and hiTh for maximums).
if(Scale > 0 and loTh>=0.0 and hiTh>=0.0) then rescale averages using dynamic range of r,g,b [0.0 -> DynamicRange(R,G,B)]
For each channel, estimate gamma function that will remap (scaled channel average * channel multiplier) to match a particular
LockVal (chosen via LockChan). Render frame using the output averages from estimated gamma.

GamMac(Clip c,int "LockChan"=1,int "Scale"=2,
\ Float "RedMul"=1.0,Float "GrnMul"=1.0, Float "BluMul"=1.0,
\ Float "Th"= 0.04,Float "loTh"=Th,Float "hiTh"=Th,
\ Float "LockVal"=128.0,Float "RngLim"=10.0,Float "GamMax"=10.0,
\ Clip "dc",
\ int "x"=20,int "y"=20,int "w"=-20,int "h"=-20,
\ Bool "Show"=True,int "Verbosity"=1
\ )

LockChan Default 1(Grn). Channel for lock to Average. [range -3 -> 2]
0 ] LockVal = Scaled(RedAve)
1 ] LockVal = Scaled(GreenAve)
2 ] LockVal = Scaled(BlueAve)
-1] LockVal = Use explicit LockVal arg (see below).
-2] LockVal = (Scaled(RedAve)+Scaled(GrnAve)+Scaled(BluAve))/3.0.
-3] LockVal = Median(Scaled(RedAve),Scaled(GrnAve),Scaled(BluAve))
Where Scaled(Channel Average) depends upon Scale, and loTh, and hiTh.

Scale, default 2 Range 0 -> 2. No Effect unless Scale > 0 and loTh and/or hiTh >= 0.0.
where described for Red Channel only:-
RedMin = Red_Channel_Minimum(ignorePerc=loTh) # Pixel minimum for red channel, ignoring up to loTh%, ie noise.
RedMax = Red_Channel_Maximum(ignorePerc=hiTh) # Pixel maximum for red channel, ignoring up to hiTh%, ie noise.
RedAve = Red_Channel_Average() # Pixel average for red Channel.
0 (Scale==0 || (loTh==-1.0 && hiTh==-1.0)) No Effect.
in_min = RedMin = GrnMin = BluMin = 0
in_max = RedMax = GrnMax = BluMax = 255
scaledAveR = RedAve
scaledAveG = GrnAve
scaledAveB = BluAve
1) Scales input channel average maximum dynamic range of R,G,B, to 0.0->(ChanAve-in_min)*255.0/(in_max-in_min+(in_max==in_min))
in_min = min(RedMin,GrnMin,BluMin)
in_max = max(RedMax,GrnMax,BluMax)
in_Rng = in_max - in_min
scaler = (in_Rng==0) ? 255.0 : 255.0 / (in_max - in_min)
scaledAveR = min(max((RedAve - in_min) * scaler,0.0),255.0)
scaledAveG = min(max((GrnAve - in_min) * scaler,0.0),255.0)
scaledAveB = min(max((BluAve - in_min) * scaler,0.0),255.0)
2) Scales input channel average dynamic range of R & G & B, Individually, to 0.0->(ChanAve-Chan_min)*255.0/(ChanMax-ChanMin)
in_RngR = RedMax - RedMin
in_RngG = GrnMax - GrnMin
in_RngB = BluMax - BluMin
scalerR = (In_RngR==0) ? 255.0 : 255.0 / (RedMax-RedMin)
scalerG = (In_RngG==0) ? 255.0 : 255.0 / (GrnMax-GrnMin)
scalerB = (In_RngB==0) ? 255.0 : 255.0 / (BluMax-BluMin)
scaledAveR = min(max((RedAve - RedMin) * scalerR,0.0),255.0)
scaledAveG = min(max((GrnAve - GrnMin) * scalerG,0.0),255.0)
scaledAveB = min(max((BluAve - BluMid) * scalerB,0.0),255.0)

RedMul, default 1.0 Red channel multiplier adjustment. [0.1 <= RedMul <= 10.0]
GrnMul, default 1.0 Green channel multiplier adjustment. [0.1 <= GrnMul <= 10.0]
BluMul, default 1.0 Blue channel multiplier adjustment. [0.1 <= BluMul <= 10.0]
Scaled averages are multiplied by their multiplier then given as args to the gamma estimator.
Allow tweaking of R,G,B channels.
Above Multipliers only shown in metrics when at least one is != 1.0 (Always shown when Verbosity=3=FULL).

Th, Default 0.04 Sets Default for loTh and hiTh. Suggest Default, 0.04(percent). [-1.0(OFF) , or 0.0 -> 1.0]
loTh, Default Th As for Ignore_low in AutoLevels, or Threshold in YPlaneMin. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding minimum R, G or B channel values.
-1.0 is OFF, input channel minimum is set to 0 as for levels(0,gamma,input_max, ... ).
If loTh >=0.0, then will scan frame looking for lowest pixel value whose cumlative sum
[including all pixels counts of lower value pixels] is greater than loTh%.
loTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).
hiTh, Default Th As for Ignore_high in AutoLevels, or Threshold in YPlaneMax. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding maximum R, G or B channel values.
-1.0 is OFF, input channel maximum set to 255, as in levels(input_min,gamma,255, ... ).
If hiTh >=0.0, then will scan frame looking for highest pixel value whose cumlative sum
[including all pixels counts of higher value pixels] is greater than hiTh%.
hiTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).

LockVal, default 128.0 Only used if LockChan = -1.0. [0.0 < LockVal < 255.0] (set via LockChan if LockChan != -1)
There is no restricted range on this (other than 0.0 < LockVal < 255.0), so if you set a stupid value,
you will likely get stupid results.

RngLim, default 10.0 If any input channel average is nearer than this to either channel minimum or channel maximum, then no effect on that channel.
[4.0 <= RngLim <= 32.0]
Allows to skip remapping of a channel where input channel average (un-scaled) is too close to either channel
minimum or maximum, ie avoid remapping of Black, White frames, or single color frames.

GamMax, default 10.0 Upper value for guess gamma [2.0 <= GamMax <= 10.0]
Starting guess upper range and limit for gamma estimator (probably best left alone).
The lower guess range and limit will be set to 1.0 / GamMax, by default 0.1.

dc, default clip c. Detection clip, Must be same ColorSpace and FrameCount as source clip, no other similarities enforced.
(can be different size, denoised etc).

x,y,w,h. All Default 20. Area of dc Detect clip frame to sample when getting averages and estimating Gamma function, allows to ignore rubbish at frame edges.
Specified as for crop ie x=10,y=20,w=-30,h=-40, as in crop(10,20,-30,-40).

Show, default true True, show metrics info on frame.
Verbosity, default 1 0 = Only upper frame metrics
1 = Upper + important ones. (default)
2 = Nearly Full metrics.
3 = Full Metrics
Upper frame metrics shown as eg:- (when Verbosity=3=FULL)

nnnnn] Flags:- 1SR
R G B
IN: 10,253 10,253 10,253
IN_AVE: 78.466 88.552 78.767
SCALED: 71.847 82.431 72.162
GAMMA: 1.135 1.000 1.123
OUTAVE: 82.431 82.422 82.451

where,
nnnnn, is the frame number.
Flags:- (Specific to current frame, can change frame to frame)
'1' = LockChan, as above, channel '1'[ScaleAveG].
Can be, '0', '1', '2' [ScaleAve Channel number LockChan=-3(median) assigns '0', '1' or '2' as appropriate]
'A'[LockChan=-2, (ScaleAveR+ScaleAveG+ScaleAveB)/3.0]
'V'[LockChan=-1, Explicit LockVal]
'S' = Scale, mode signfied by color.
Greyed out. Scale = 0(No Effect).May be Greyed out if all channels Min/Max are 0,255.
White. Scale = 1[Scales input channel average maximum dynamic range of R,G,B]
Orange. Scale = 2[Scales input channel average dynamic range of R and G and B, Individually]
'R' = Limited by RngLim, mode signfied by color.
Greyed out. Not Range Limited.
Red, at least 1 channel has remapping disabled.
IN: Shows comma separated channel minimum and maximum (dependent upon Scale, loTh, hiTh).
IN_AVE: Input channel averages.
SCALED: Scaled input averages, (dependent upon Scale, loTh, hiTh, channel minumums and maximums).
GAMMA: Estimated gamma to achieve lockval for channel. (dependent upon pretty much everything).
OUTAVE: Output channel average ie rendered result.

ALL metrics derived from the detection clip dc.



Fred, Added dc (detection clip) and modified args as per orders.
The RngLim thing still dont work at all well, I'll havta fix that.

[videoFred]

Fred, Added dc (detection clip) and modified args as per orders.

Thank you! It is good to set x,y,w,h to 20 by default.

As you know, I already use RemoveDirt() before Gammac. So the detection clip has no use for me.. But I could try extreme settings and see what I get.


The RngLim thing still dont work at all well, I'll havta fix that.

For now, I add a small 2 to 6 pixels pure white border before Gammac to avoid over-adjusting and this works very well. :)


PS: Gammac works great on my old 1970's photos too!
http://www.super-8.be/Doom/29013.jpg

http://www.super-8.be/Doom/landscape.jpg

Fred.

[StainlessS]

In the words of Harry Potter, "I love magic". :)

Perhaps that's the Hogwart's Express. (at least platform 9.75)

For now, I add a small 2 to 6 pixels pure white border before Gammac to avoid over-adjusting
I'll add output r,g,b max and min targets, as currently set at 0, and 255 (should avoid above, probably
one for each min and max, not for each channel, unless that is required).

[videoFred]

In the words of Harry Potter, "I love magic". :)
Me too ;)

Perhaps that's the Hogwart's Express. (at least platform 9.75)
Haha, no it's the last steam engine from the Belgian Railroad. His last official ride was way back in 1966. The photo is from a 1970's steam festival.

I had to do some additional color corrections on the steam engine picture, but the landscape picture is Gammac only, I only had to do some very minor RedMul and Blumul corrections.

Fred.

[StainlessS]

GamMac v1.06Beta3:- LINK DELETED

Added omin, omax args. Mod to RngLim.


GamMac(), [Gamma Machine] An extraordinary Idea by VideoFred (the gent from Gent). Coded by StainlessS.

Home Thread:- http://forum.doom9.org/showthread.php?p=1774281#post1774281
Idea:- http://forum.doom9.org/showthread.php?t=173683

RGB Only.

Useful to correct color cast on old 8mm films.
Alters channel pixel average to match LockChan using Gamma correction. (By default alters Red and Blue channels to match Green).
Additional tweaking via RedMul, GrnMul and BluMul multipliers.

What it does(roughly):-
Firstly, RAW input channel Ranges are measured for all three channels (see RngLim).
If ALL THREE raw input ranges are less than RngLim (single color frame), then for current frame,
there is no scaling nor gamma estimation, and only linear rendering is done to output range omin -> omax.
OtherWise,
If ANY ONE channel input range is less than RngLim and Scale==2, then Scale is (for current frame) knocked down to Scale=1.
Get Channel averages, minimums, and maximums (using loTh for minimums and hiTh for maximums).
if(Scale==0 || loTh<0.0 a|| hiTh<0.0) then
No rescaling.
if(Scale == 1 and loTh>=0.0 and hiTh>=0.0) then
rescales averages using combined dynamic range of r,g,b ie 0.0 -> (max(redMax,grnMax,bluMax) - min(redMin,grnMin,bluMin)).
else if(Scale == 2 and loTh>=0.0 and hiTh>=0.0) then
rescales averages using separate dynamic ranges ie 0.0->(redMax-redMin), 0.0->(grnMax-grnMin), 0.0->(bluMax-bluMin).
For each channel, estimate gamma function that will remap (scaled channel average * channel multiplier) to match a particular
LockVal (chosen via LockChan) when rendered to the chosen output range specified by omin and omax.
Then renders frame using the output averages from estimated gamma with output channel minimums at omin, and maximums at omax.

GamMac(Clip c,int "LockChan"=1,int "Scale"=2,
\ Float "RedMul"=1.0,Float "GrnMul"=1.0, Float "BluMul"=1.0,
\ Float "Th"= 0.04,Float "loTh"=Th,Float "hiTh"=Th,
\ Float "LockVal"=128.0,int "RngLim"=11,Float "GamMax"=10.0,
\ Clip "dc",
\ int "x"=20,int "y"=20,int "w"=-20,int "h"=-20,
\ int "omin"=0, int "omax"=255,
\ Bool "Show"=True,int "Verbosity"=1
\ )

LockChan Default 1(Grn). Channel for lock to Average. [range -3 -> 2]
0 ] LockVal = Scaled(RedAve)
1 ] LockVal = Scaled(GreenAve)
2 ] LockVal = Scaled(BlueAve)
-1] LockVal = Use explicit LockVal arg (see below).
-2] LockVal = (Scaled(RedAve)+Scaled(GrnAve)+Scaled(BluAve))/3.0. [Mean]
-3] LockVal = Median(Scaled(RedAve),Scaled(GrnAve),Scaled(BluAve))
Where Scaled(Channel Average) depends upon RngLim, Scale, and loTh, and hiTh.

Scale, default 2 Range 0 -> 2.
There is NO SCALING DONE if ALL THREE channels range is less than RngLim, see RngLim, linear render only.
If ANY ONE channel input range is less than RngLim and Scale==2, then Scale is (for current frame) knocked down to Scale=1.

where some described for Red Channel only:-
redMin = RedChanMin(ignorePerc=loTh) # Pixel minimum for red channel, ignoring up to loTh%, ie noise.
redMax = RedChanMax(ignorePerc=hiTh) # Pixel maximum for red channel, ignoring up to hiTh%, ie noise.
redAve = RedChanAve() # Pixel average for red Channel.
redRng = redMax - redMin
inMin = min(redMin,grnMin,bluMin) # Min of minimums
inMax = max(redMax,grnMax,bluMax) # Max of maximums

0 (Scale==0 || (loTh==-1.0 && hiTh==-1.0)) # No Effect on scale.
scaledAveR = redAve
scaledAveG = grnAve
scaledAveB = bluAve
1) Scales input channel average maximum dynamic range of R,G,B, to 0.0->(ChanAve-inMin)*255.0/(inMax-inMin)
scaler = 255.0 / (inMax - inMin)
scaledAveR = min(max((RedAve - inMin) * scaler,0.0),255.0)
scaledAveG = min(max((GrnAve - inMin) * scaler,0.0),255.0)
scaledAveB = min(max((BluAve - inMin) * scaler,0.0),255.0)
2) Scales input channel average dynamic range of R & G & B, Individually, to 0.0->(ChanAve-Chan_min)*255.0/(ChanMax-ChanMin)
scalerR = 255.0 / (redMax-redMin)
scalerG = 255.0 / (grnMax-grnMin)
scalerB = 255.0 / (bluMax-bluMin)
scaledAveR = min(max((redAve - redMin) * scalerR,0.0),255.0)
scaledAveG = min(max((grnAve - grnMin) * scalerG,0.0),255.0)
scaledAveB = min(max((bluAve - bluMid) * scalerB,0.0),255.0)

RedMul, default 1.0 Red channel multiplier adjustment. [0.1 <= RedMul <= 10.0]
GrnMul, default 1.0 Green channel multiplier adjustment. [0.1 <= GrnMul <= 10.0]
BluMul, default 1.0 Blue channel multiplier adjustment. [0.1 <= BluMul <= 10.0]
Scaled averages are multiplied by their multiplier then given as args to the gamma estimator.
Allow tweaking of R,G,B channels.
Above Multipliers only shown in metrics when at least one is != 1.0 (Always shown when Verbosity=3=FULL).

Th, Default 0.04 Sets Default for loTh and hiTh. Suggest Default, 0.04(percent). [-1.0(OFF) , or 0.0 -> 1.0]
loTh, Default Th As for Ignore_low in AutoLevels, or Threshold in YPlaneMin. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding minimum R, G or B channel values.
-1.0 is OFF, input channel minimum is set to 0 as for levels(0,gamma,input_max, ... ).
If loTh >=0.0, then will scan frame looking for lowest pixel value whose cumlative sum
[including all pixels counts of lower value pixels] is greater than loTh%.
loTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).
hiTh, Default Th As for Ignore_high in AutoLevels, or Threshold in YPlaneMax. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding maximum R, G or B channel values.
-1.0 is OFF, input channel maximum set to 255, as in levels(input_min,gamma,255, ... ).
If hiTh >=0.0, then will scan frame looking for highest pixel value whose cumlative sum
[including all pixels counts of higher value pixels] is greater than hiTh%.
hiTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).

LockVal, default 128.0 Only used if LockChan = -1. [0.0 < LockVal < 255.0] (set via LockChan if LockChan != -1)
There is no restricted range on this (other than 0.0 < LockVal < 255.0), so if you set a stupid value,
you will likely get stupid results.

RngLim, default 11 [1 <= RngLim <= 32]
If ALL THREE RAW input channel ranges ie (ChannelMax(max(hiTh,0.0))-ChannelMin(max(loTh,0.0))) are less than RngLim then
all scaling is disabled, and remapping is linear without gamma estimation, to range omin -> omax,
ie avoid remapping of Black, White frames, or single color frames.

GamMax, default 10.0 Upper value for guess gamma [2.0 <= GamMax <= 10.0]
Starting guess upper range and limit for gamma estimator (probably best left alone).
The lower guess range and limit will be set to 1.0 / GamMax, by default 0.1.

dc, default clip c. Detection clip, Must be same ColorSpace and FrameCount as source clip, no other similarities enforced.
(can be different size, denoised etc).

x,y, Both default 20. Area of dc Detect clip frame to sample when getting averages and estimating Gamma function, allows to ignore rubbish at frame edges.
w,h, Both default -20. Specified as for crop eg x=10,y=20,w=-30,h=-40, as in crop(10,20,-30,-40).

omin, default 0. Output limits for all three R, and G, and B channels. [Range 0 -> 16]
omax, default 255. [Range 239 -> 255] (extremes 16->239 allow for Studio RGB output).
May want to give yourself a little head/foot room by setting eg omin=5, omax=250, so that you leave a little room for
further manual color tweaking.

Show, default true True, show metrics info on frame.
Verbosity, default 1 0 = Only upper frame metrics
1 = Upper + important ones. (default)
2 = Nearly Full metrics.
3 = Full Metrics
Upper frame metrics shown as eg:- (when Verbosity=3=FULL)

nnnnn] Flags:- 1SR
R G B
RAW: 10,253 10,253 10,253
IN: 10,253 10,253 10,253
IN_AVE: 78.466 88.552 78.767
SCALED: 71.847 82.431 72.162
GAMMA: 1.135 1.000 1.123
OUTAVE: 82.431 82.422 82.451

where,
nnnnn, is the frame number.
Flags:- (Specific to current frame, can change frame to frame)
'1' = LockChan, as above, channel '1'[ScaleAveG].
Can be, '0', '1', '2' [ScaleAve Channel number LockChan=-3(median) assigns '0', '1' or '2' as appropriate]
'A'[LockChan=-2, (ScaleAveR+ScaleAveG+ScaleAveB)/3.0]
'V'[LockChan=-1, Explicit LockVal]
'S' = Scale, mode signfied by color.
Greyed out. Scale = 0(No Effect). May be Greyed out if all channels Min/Max are 0,255.
White. Scale = 1[Scales input channel average maximum dynamic range of R,G,B]
Orange. Scale = 2[Scales input channel average dynamic range of R and G and B, Individually]
'R' = Limited by RngLim, mode signfied by color.
Greyed out. Not Range Limited.
Red, at least 1 channel has remapping disabled.
RAW: Shows RAW comma separated channel minimum and maximum, eg ChannelMin(max(loTh,0.0)) and (ChannelMax(max(hiTh,0.0)),
only shown if Verbosity>=3 or, if any RAW input range is less than RngLim AND any of the RAW inputs are different
to the equivalent standard input.
IN: Shows comma separated channel minimum and maximum (dependent upon Scale, loTh, hiTh).
IN_AVE: Input channel averages.
SCALED: Scaled input averages, (dependent upon Scale, loTh, hiTh, channel minumums and maximums).
GAMMA: Estimated gamma to achieve lockval for channel. (dependent upon pretty much everything).
OUTAVE: Output channel average ie rendered result.

ALL metrics derived from the detection clip dc.


Not really sure how I should process low range frames (as by RngLim), could well be discontinuities in fades.

EDIT: Fred, omin, omax obviates need for a "few pixels of black,white border" (I hope).

[StainlessS]

GamMac v1.06 Beta 4, new version:- LINK REMOVED

Added Coords arg.

Coords, default False. If True, then shows DC clip with dotted lines showing the x,y,w,h coords plotted on frame. (All other functionality disabled).



GamMac(), [Gamma Machine] An extraordinary Idea by VideoFred (the gent from Gent). Coded by StainlessS.

Home Thread:- http://forum.doom9.org/showthread.php?p=1774281#post1774281
Idea:- http://forum.doom9.org/showthread.php?t=173683

RGB Only.

Useful to correct color cast on old 8mm films.
Alters channel pixel average to match LockChan using Gamma correction. (By default alters Red and Blue channels to match Green).
Additional tweaking via RedMul, GrnMul and BluMul multipliers.

What it does(roughly):-
Firstly, RAW input channel Ranges are measured for all three channels (see RngLim).
If ALL THREE raw input ranges are less than RngLim (single color frame), then for current frame,
there is no scaling nor gamma estimation, and only linear rendering is done to output range omin -> omax.
[EDIT: Channel multipliers are still applied though].
OtherWise,
If ANY ONE channel input range is less than RngLim and Scale==2, then Scale is (for current frame) knocked down to Scale=1.
Get Channel averages, minimums, and maximums (using loTh for minimums and hiTh for maximums).
if(Scale==0 || loTh<0.0 || hiTh<0.0) then
EDIT: if(Scale==0 || (loTh<0.0 AND hiTh<0.0)) then
No rescaling.
if(Scale == 1 and loTh>=0.0 and hiTh>=0.0) then
if(Scale == 1 and (loTh>=0.0 OR hiTh>=0.0)) then
rescales averages using combined dynamic range of r,g,b ie 0.0 -> (max(redMax,grnMax,bluMax) - min(redMin,grnMin,bluMin)).
else if(Scale == 2 and loTh>=0.0 and hiTh>=0.0) then
else if(Scale == 2 AND (loTh>=0.0 OR hiTh>=0.0)) then
rescales averages using separate dynamic ranges ie 0.0->(redMax-redMin), 0.0->(grnMax-grnMin), 0.0->(bluMax-bluMin).
For each channel, estimate gamma function that will remap (scaled channel average * channel multiplier) to match a particular
LockVal (chosen via LockChan) when rendered to the chosen output range specified by omin and omax.
Then renders frame using the output averages from estimated gamma with output channel minimums at omin, and maximums at omax.

GamMac(Clip c,int "LockChan"=1,int "Scale"=2,
\ Float "RedMul"=1.0,Float "GrnMul"=1.0, Float "BluMul"=1.0,
\ Float "Th"= 0.04,Float "loTh"=Th,Float "hiTh"=Th,
\ Float "LockVal"=128.0,int "RngLim"=11,Float "GamMax"=10.0,
\ Clip "dc",
\ int "x"=20,int "y"=20,int "w"=-20,int "h"=-20,
\ int "omin"=0, int "omax"=255,
\ Bool "Show"=True,int "Verbosity"=1,Bool "Coords"=false
\ )

LockChan Default 1(Grn). Channel for lock to Average. [range -3 -> 2]
0 ] LockVal = Scaled(RedAve)
1 ] LockVal = Scaled(GrnAve)
2 ] LockVal = Scaled(BluAve)
-1] LockVal = Use explicit LockVal arg (see below).
-2] LockVal = (Scaled(RedAve)+Scaled(GrnAve)+Scaled(BluAve))/3.0. [Mean]
-3] LockVal = Median(Scaled(RedAve),Scaled(GrnAve),Scaled(BluAve))
Where Scaled(Channel Average) depends upon RngLim, Scale, and loTh, and hiTh.

Scale, default 2 Range 0 -> 2.
There is NO SCALING DONE if ALL THREE channels range is less than RngLim, see RngLim, linear render only.
If ANY ONE channel input range is less than RngLim and Scale==2, then Scale is (for current frame) knocked down to Scale=1.

where some described for Red Channel only:-
redMin = RedChanMin(ignorePerc=loTh) # Pixel minimum for red channel, ignoring up to loTh%, ie noise.
redMax = RedChanMax(ignorePerc=hiTh) # Pixel maximum for red channel, ignoring up to hiTh%, ie noise.
redAve = RedChanAve() # Pixel average for red Channel.
redRng = redMax - redMin
inMin = min(redMin,grnMin,bluMin) # Min of minimums
inMax = max(redMax,grnMax,bluMax) # Max of maximums

0 (Scale==0 || (loTh==-1.0 && hiTh==-1.0)) # No Effect on scale.
scaledAveR = redAve
scaledAveG = grnAve
scaledAveB = bluAve
1) Scales input channel average maximum dynamic range of R,G,B, to 0.0->(ChanAve-inMin)*255.0/(inMax-inMin)
scaler = 255.0 / (inMax - inMin)
scaledAveR = min(max((RedAve - inMin) * scaler,0.0),255.0)
scaledAveG = min(max((GrnAve - inMin) * scaler,0.0),255.0)
scaledAveB = min(max((BluAve - inMin) * scaler,0.0),255.0)
2) Scales input channel average dynamic range of R & G & B, Individually, to 0.0->(ChanAve-Chan_min)*255.0/(ChanMax-ChanMin)
scalerR = 255.0 / (redMax-redMin)
scalerG = 255.0 / (grnMax-grnMin)
scalerB = 255.0 / (bluMax-bluMin)
scaledAveR = min(max((redAve - redMin) * scalerR,0.0),255.0)
scaledAveG = min(max((grnAve - grnMin) * scalerG,0.0),255.0)
scaledAveB = min(max((bluAve - bluMid) * scalerB,0.0),255.0)

RedMul, default 1.0 Red channel multiplier adjustment. [0.1 <= RedMul <= 10.0]
GrnMul, default 1.0 Green channel multiplier adjustment. [0.1 <= GrnMul <= 10.0]
BluMul, default 1.0 Blue channel multiplier adjustment. [0.1 <= BluMul <= 10.0]
Scaled averages are multiplied by their multiplier then given as args to the gamma estimator.
Allow tweaking of R,G,B channels.
Above Multipliers only shown in metrics when at least one is != 1.0 (Always shown when Verbosity=3=FULL).

Th, Default 0.04 Sets Default for loTh and hiTh. Suggest Default, 0.04(percent). [-1.0(OFF) , or 0.0 -> 1.0]
loTh, Default Th As for Ignore_low in AutoLevels, or Threshold in YPlaneMin. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding minimum R, G or B channel values.
-1.0 is OFF, input channel minimum is set to 0 as for levels(0,gamma,input_max, ... ).
If loTh >=0.0, then will scan frame looking for lowest pixel value whose cumulative sum
[including all pixels counts of lower value pixels] is greater than loTh%.
loTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).
hiTh, Default Th As for Ignore_high in AutoLevels, or Threshold in YPlaneMax. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding maximum R, G or B channel values.
-1.0 is OFF, input channel maximum set to 255, as in levels(input_min,gamma,255, ... ).
If hiTh >=0.0, then will scan frame looking for highest pixel value whose cumulative sum
[including all pixels counts of higher value pixels] is greater than hiTh%.
hiTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).

LockVal, default 128.0 Only used if LockChan = -1. [0.0 < LockVal < 255.0] (set via LockChan if LockChan != -1)
There is no restricted range on this (other than 0.0 < LockVal < 255.0), so if you set a stupid value,
you will likely get stupid results.

RngLim, default 11 [1 <= RngLim <= 32]
If ALL THREE RAW input channel ranges ie (ChannelMax(max(hiTh,0.0))-ChannelMin(max(loTh,0.0))) are less than RngLim then
all scaling is disabled, and remapping is linear without gamma estimation, to range omin -> omax,
ie avoid remapping of Black, White frames, or single color frames.

GamMax, default 10.0 Upper value for guess gamma [2.0 <= GamMax <= 10.0]
Starting guess upper range and limit for gamma estimator (probably best left alone).
The lower guess range and limit will be set to 1.0 / GamMax, by default 0.1.

dc, default clip c. Detection clip, Must be same ColorSpace and FrameCount as source clip, no other similarities enforced.
(can be different size, denoised etc).

x,y, Both default 20. Area of dc Detect clip frame to sample when getting averages and estimating Gamma function, allows to ignore rubbish at frame edges.
w,h, Both default -20. Specified as for crop eg x=10,y=20,w=-30,h=-40, as in crop(10,20,-30,-40).

omin, default 0. Output limits for all three R, and G, and B channels. [Range 0 -> 16]
omax, default 255. [Range 239 -> 255] (extremes 16->239 allow for Studio RGB output).
May want to give yourself a little head/foot room by setting eg omin=5, omax=250, so that you leave a little room for
further manual color tweaking.

Show, default true True, show metrics info on frame.
Verbosity, default 1 0 = Only upper frame metrics
1 = Upper + important ones. (default)
2 = Nearly Full metrics.
3 = Full Metrics
Upper frame metrics shown as eg:- (when Verbosity=3=FULL)

nnnnn] Flags:- 1SR
R G B
RAW: 10,253 10,253 10,253
IN: 10,253 10,253 10,253
IN_AVE: 78.466 88.552 78.767
SCALED: 71.847 82.431 72.162
GAMMA: 1.135 1.000 1.123
OUTAVE: 82.431 82.422 82.451

where,
nnnnn, is the frame number.
Flags:- (Specific to current frame, can change frame to frame)
'1' = LockChan, as above, channel '1'[ScaleAveG].
Can be, '0', '1', '2' [ScaleAve Channel number LockChan=-3(median) assigns '0', '1' or '2' as appropriate]
'A'[LockChan=-2, (ScaleAveR+ScaleAveG+ScaleAveB)/3.0]
'V'[LockChan=-1, Explicit LockVal]
'S' = Scale, mode signified by color.
Greyed out. Scale = 0(No Effect). May be Greyed out if all channels Min/Max are 0,255.
White. Scale = 1[Scales input channel average maximum dynamic range of R,G,B]
Orange. Scale = 2[Scales input channel average dynamic range of R and G and B, Individually]
'R' = Limited by RngLim, mode signfied by color.
Greyed out. Not Range Limited.
Red, at least 1 channel has remapping disabled.
RAW: Shows RAW comma separated channel minimum and maximum, eg ChannelMin(max(loTh,0.0)) and (ChannelMax(max(hiTh,0.0)),
only shown if Verbosity>=3 or, if any RAW input range is less than RngLim AND any of the RAW inputs are different
to the equivalent standard input.
IN: Shows comma separated channel minimum and maximum (dependent upon Scale, loTh, hiTh).
IN_AVE: Input channel averages.
SCALED: Scaled input averages, (dependent upon Scale, loTh, hiTh, channel minimums and maximums).
GAMMA: Estimated gamma to achieve lockval for channel. (dependent upon pretty much everything).
OUTAVE: Output channel average ie rendered result.

ALL metrics derived from the detection clip dc (Including OutAve's).

Coords, default False. If True, then shows DC clip with dotted lines showing the x,y,w,h coords plotted on frame. (All other functionality disabled).

[StainlessS]

GamMac v1.06 Beta 5, new version:- LINK REMOVED

Negative LockChan was broken, fixed. Some metrics mainly S flag color fixed.

Previous post DOCS not changed.

EDIT:
To use coords arg and detection clip not used, (DC defaults to Last)

Return GamMac(Last,x=x,y=y,w=w,h=h,Coords=True) # Show Coords only

or with DC detection clip

Return GamMac(DC,x=x,y=y,w=w,h=h,Coords=True) # Show Coords only
# or
#Return GamMac(dc=DC,x=x,y=y,w=w,h=h,Coords=True)


EDIT:
How it looks, Verbocity=1
https://s20.postimg.cc/hhcfqen3x/pup0000_zpsxaw0pgfv.png (https://postimg.cc/image/jlwsrhoqh/)

and original with detect coords shown
https://s20.postimg.cc/5tidvuxz1/pup_Coord0000_zpsuzm6foic.png (https://postimg.cc/image/8nlj9b055/)

EDIT:
And coords shown avoiding detect on original subtitles
https://s20.postimg.cc/g4uqoipod/Coords0000_zpsy7ir1e6x.png (https://postimg.cc/image/t90b17hq1/)

And result
https://s20.postimg.cc/w4de82lq5/Miss_Coords0000_zps85k72spw.png (https://postimg.cc/image/rih9zq06x/)

[johnmeyer]

OK, I need to get off the sidelines and get into this game. Harry Potter magic doesn't begin to describe what I'm seeing. Amazing stuff, StainlessS!

I'm working on a complete re-write of the software for my shutterless projector transfer system, and I need to integrate this into my new workflow.

[StainlessS]

All, but all magic is down to Videofred, i' m just a grunt.

Videofred ain't no muggle. [EDIT: Yoda had some say so too, yo dude, Yoda for king, or maybe Pope or something].

[johnmeyer]

I know what VideoFred can do, and it is beyond remarkable. However, I've followed this development, and you came up with the code that makes everything work.

I hope to get to this next week, and I'll report back on what I'm able to do with it.

[StainlessS]

Post #1 of 2
GamMac v1.06 Beta6, New Version:- LINK REMOVED
(~998KB, Included Puppy.png, LennaRed.png, and GreenChurch.png)

Updates mainly cosmetic.
Increased number of Verbosity levels to 5 (default=2, 5=Show version info + ALL metrics, 0=show metrics Flags line only).
A few mods to docs.
Added Subs to 4 window output, optional coords shown (included avs script).
EDIT: The DC clip (detect clip) coords now changed from all white dotted lines to alternate white and black dots.

Docs

GamMac(), [Gamma Machine] An extraordinary Idea by VideoFred (the gent from Gent). Coded by StainlessS.

Home Thread:- http://forum.doom9.org/showthread.php?p=1774281#post1774281
Idea:- http://forum.doom9.org/showthread.php?t=173683

RGB Only.

Useful to correct color cast on old 8mm films.
Alters channel pixel average to match LockChan using Gamma correction. (By default alters Red and Blue channels to match Green).
Additional tweaking via RedMul, GrnMul and BluMul multipliers.

What it does(roughly):-
Firstly, RAW input channel Ranges are measured for all three channels (see RngLim).
If ALL THREE raw input ranges are less than RngLim (single color frame), then for current frame,
there is no scaling nor gamma estimation, and only linear rendering is done to output range omin -> omax.
[Channels multipliers RedMul, GrnMul and BluMul still applied though.]
OtherWise,
If ANY ONE channel input range is less than RngLim and Scale==2, then Scale is (for current frame) knocked down to Scale=1.
Get Channel averages, minimums, and maximums (using loTh for minimums and hiTh for maximums).
if(Scale==0 OR (loTh<0.0 AND hiTh<0.0)) then
No rescaling.
if(Scale == 1 AND (loTh>=0.0 OR hiTh>=0.0)) then
rescales averages using combined dynamic range of r,g,b ie 0.0 -> (max(redMax,grnMax,bluMax) - min(redMin,grnMin,bluMin)).
else if(Scale == 2 AND (loTh>=0.0 OR hiTh>=0.0)) then
rescales averages using separate dynamic ranges ie 0.0->(redMax-redMin), 0.0->(grnMax-grnMin), 0.0->(bluMax-bluMin).
For each channel, estimate gamma function that will remap (scaled channel average * channel multiplier) to match a particular
LockVal (chosen via LockChan) when rendered to the chosen output range specified by omin and omax.
Then renders frame using the output averages from estimated gamma with output channel minimums at omin, and maximums at omax.

GamMac(Clip c,int "LockChan"=1,int "Scale"=2,
\ Float "RedMul"=1.0,Float "GrnMul"=1.0, Float "BluMul"=1.0,
\ Float "Th"= 0.04,Float "loTh"=Th,Float "hiTh"=Th,
\ Float "LockVal"=128.0,int "RngLim"=11,Float "GamMax"=10.0,
\ Clip "dc",
\ int "x"=20,int "y"=20,int "w"=-20,int "h"=-20,
\ int "omin"=0, int "omax"=255,
\ Bool "Show"=True,int "Verbosity"=2,Bool "Coords"=false
\ )

LockChan Default 1(Grn). Channel for lock to Average. [range -3 -> 2]
0 ] LockVal = Scaled(RedAve)
1 ] LockVal = Scaled(GrnAve)
2 ] LockVal = Scaled(BluAve)
-1] LockVal = Use explicit LockVal arg (see below).
-2] LockVal = (Scaled(RedAve)+Scaled(GrnAve)+Scaled(BluAve))/3.0. [Mean]
-3] LockVal = Median(Scaled(RedAve),Scaled(GrnAve),Scaled(BluAve))
Where Scaled(Channel Average) depends upon RngLim, Scale, and loTh, and hiTh.

Scale, default 2 Range 0 -> 2.
There is NO SCALING DONE if ALL THREE channels range is less than RngLim, see RngLim, linear render only.
If ANY ONE channel input range is less than RngLim and Scale==2, then Scale is (for current frame) knocked down to Scale=1.

where some described for Red Channel only:-
redMin = RedChanMin(ignorePerc=loTh) # Pixel minimum for red channel, ignoring up to loTh%, ie noise.
redMax = RedChanMax(ignorePerc=hiTh) # Pixel maximum for red channel, ignoring up to hiTh%, ie noise.
redAve = RedChanAve() # Pixel average for red Channel.
redRng = redMax - redMin
inMin = min(redMin,grnMin,bluMin) # Min of minimums
inMax = max(redMax,grnMax,bluMax) # Max of maximums

0 (Scale==0 || (loTh==-1.0 && hiTh==-1.0)) # No Effect on scale.
scaledAveR = redAve
scaledAveG = grnAve
scaledAveB = bluAve
1) Scales input channel average maximum dynamic range of R,G,B, to 0.0->(ChanAve-inMin)*255.0/(inMax-inMin)
scaler = 255.0 / (inMax - inMin)
scaledAveR = min(max((RedAve - inMin) * scaler,0.0),255.0)
scaledAveG = min(max((GrnAve - inMin) * scaler,0.0),255.0)
scaledAveB = min(max((BluAve - inMin) * scaler,0.0),255.0)
2) Scales input channel average dynamic range of R & G & B, Individually, to 0.0->(ChanAve-Chan_min)*255.0/(ChanMax-ChanMin)
scalerR = 255.0 / (redMax-redMin)
scalerG = 255.0 / (grnMax-grnMin)
scalerB = 255.0 / (bluMax-bluMin)
scaledAveR = min(max((redAve - redMin) * scalerR,0.0),255.0)
scaledAveG = min(max((grnAve - grnMin) * scalerG,0.0),255.0)
scaledAveB = min(max((bluAve - bluMid) * scalerB,0.0),255.0)

RedMul, default 1.0 Red channel multiplier adjustment. [0.1 <= RedMul <= 10.0]
GrnMul, default 1.0 Green channel multiplier adjustment. [0.1 <= GrnMul <= 10.0]
BluMul, default 1.0 Blue channel multiplier adjustment. [0.1 <= BluMul <= 10.0]
Scaled averages are multiplied by their multiplier then given as args to the gamma estimator.
Allow tweaking of R,G,B channels.
Above Multipliers only shown in metrics when at least one is != 1.0 (Always shown when Verbosity=3=FULL).

Th, Default 0.04 Sets Default for loTh and hiTh. Suggest Default, 0.04(percent). [-1.0(OFF) , or 0.0 -> 1.0]
loTh, Default Th As for Ignore_low in AutoLevels, or Threshold in YPlaneMin. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding minimum R, G or B channel values.
-1.0 is OFF, input channel minimum is set to 0 as for levels(0,gamma,input_max, ... ).
If loTh >=0.0, then will scan frame looking for lowest pixel value whose cumulative sum
[including all pixels counts of lower value pixels] is greater than loTh%.
loTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).
hiTh, Default Th As for Ignore_high in AutoLevels, or Threshold in YPlaneMax. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding maximum R, G or B channel values.
-1.0 is OFF, input channel maximum set to 255, as in levels(input_min,gamma,255, ... ).
If hiTh >=0.0, then will scan frame looking for highest pixel value whose cumulative sum
[including all pixels counts of higher value pixels] is greater than hiTh%.
hiTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).

LockVal, default 128.0 Only used if LockChan = -1. [0.0 < LockVal < 255.0] (set via LockChan if LockChan != -1)
There is no restricted range on this (other than 0.0 < LockVal < 255.0), so if you set a stupid value,
you will likely get stupid results.

RngLim, default 11 [1 <= RngLim <= 32]
If ALL THREE RAW input channel ranges ie (ChannelMax(max(hiTh,0.0))-ChannelMin(max(loTh,0.0))) are less than RngLim then
all scaling is disabled, and remapping is linear without gamma estimation, to range omin -> omax,
ie avoid remapping of Black, White frames, or single color frames.

GamMax, default 10.0 Upper value for guess gamma [2.0 <= GamMax <= 10.0]
Starting guess upper range and limit for gamma estimator (probably best left alone).
The lower guess range and limit will be set to 1.0 / GamMax, by default 0.1.

dc, default clip c. Detection clip, Must be same ColorSpace and FrameCount as source clip, no other similarities enforced.
(can be different size, denoised etc).

x,y, Both default 20. Area of dc Detect clip frame to sample when getting averages and estimating Gamma function, allows to ignore rubbish at frame edges.
w,h, Both default -20. Specified as for crop eg x=10,y=20,w=-30,h=-40, as in crop(10,20,-30,-40).

omin, default 0. Output limits for all three R, and G, and B channels. [Range 0 -> 16]
omax, default 255. [Range 239 -> 255] (extremes 16->239 allow for Studio RGB output).
May want to give yourself a little head/foot room by setting eg omin=5, omax=250, so that you leave a little room for
further manual color tweaking.

Show, default true True, show metrics info on frame.
Verbosity, default 2 0 = Only upper frame metrics Flags line only
1 = Upper frame metrics
2 = Upper + important ones. (default)
3 = Nearly Full metrics.
4 = Full Metrics except version info
5 = Full Metrics including version info
Upper frame metrics shown as eg:- (when Verbosity=5=FULL)

nnnnn] Flags:- 1SR
R G B
RAW: 10,253 10,253 10,253
IN: 10,253 10,253 10,253
IN_AVE: 78.466 88.552 78.767
SCALED: 71.847 82.431 72.162
GAMMA: 1.135 1.000 1.123
OUTAVE: 82.431 82.422 82.451

where,
nnnnn, is the frame number.
Flags:- (Specific to current frame, can change frame to frame)
'1' = LockChan, as above, channel '1'[ScaleAveG].
Can be, '0', '1', '2' [ScaleAve Channel number LockChan=-3(median) assigns '0', '1' or '2' as appropriate]
'A'[LockChan=-2, (ScaleAveR+ScaleAveG+ScaleAveB)/3.0]
'V'[LockChan=-1, Explicit LockVal]
'S' = Scale, mode signified by color.
Greyed out. Scale = 0(No Effect). May be Greyed out if all channels Min/Max are 0,255.
White. Scale = 1[Scales input channel average maximum dynamic range of R,G,B]
Orange. Scale = 2[Scales input channel average dynamic range of R and G and B, Individually]
'R' = Limited by RngLim, mode signfied by color.
Greyed out. Not Range Limited.
Red, at least 1 channel has remapping disabled.
RAW: Shows RAW comma separated channel minimum and maximum, eg ChannelMin(max(loTh,0.0)) and (ChannelMax(max(hiTh,0.0)),
only shown if Verbosity>=3 or, if any RAW input range is less than RngLim AND any of the RAW inputs are different
to the equivalent standard input.
IN: Shows comma separated channel minimum and maximum (dependent upon Scale, loTh, hiTh).
IN_AVE: Input channel averages.
SCALED: Scaled input averages, (dependent upon Scale, loTh, hiTh, channel minimums and maximums).
GAMMA: Estimated gamma to achieve lockval for channel. (dependent upon pretty much everything).
OUTAVE: Output channel average ie rendered result.

ALL metrics derived from the detection clip dc (Including OutAve's).

Coords, default False. If True, then shows DC clip with dotted lines showing the x,y,w,h coords plotted on frame. (All other functionality disabled).

[StainlessS]

Post #2 of 2

Included script showing Coords


Imagesource("GreenChurch.png",end=0)
#Imagesource("Puppy.png",end=0)
#Imagesource("lennaRed.png",end=0)

ConvertToRGB24.KillAudio
#Spline36Resize(512,384)
O=Last
DC=Last

#DC=DC.Blur(1.0) # Detection Clip (uses source clip if dc not supplied, Denoised or whatever)

LockChan = 1 # Chan for lock to Ave, 0=R, 1=G, 2=B
# -1 = Use LockVal below.
# -2 = LockVal=(RedAve+GrnAve+BluAve)/3.0 for LockVal.
# -3 = LockVal=Median(RedAve,GrnAve,BluAve)
Scale=2
RedMul = 1.0 # Required Ave multiplier for Red Channel, applied when requesting GuessGamma(reqAve*RedMul), Even applied when LockChan=-1.
GrnMul = 1.0 # Same for Green channel. GrnMul even applies when LockChan is Green Channel, etc for chans.
BluMul = 1.0 # Same for Blue channel. Allows tinkering/fine tuning.
Th = 0.04
LockVal = 128.0 # Only valid if LockChan == -1
RngLim = 11
GamMax = 10.0
Show = True # Metrics
Verb = 1 # Verbocity FULL
SHOWCOORDS= True # Show Original with Coords

x =5 # Coords (for dc Detection Clip)
y =5
w=-5
h=-5

omin=5 # Output channels minimum (footroom for manual editing).
omax=250 # Output channels maximum (headroom for manual editing).

#Return GamMac(DC,x=x,y=y,w=w,h=h,Coords=True) # Show Coords only

Scale=0
A_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
A=GamMac(LockChan=LockChan,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,LockVal=LockVal,RngLim=RngLim,GamMax=GamMax,
\ dc=DC,
\ x=x,y=y,w=w,h=h,
\ omin=omin,omax=omax,
\ Show=Show,Verbosity=Verb)


Scale=1 BluMul=1.05
B_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
B=GamMac(LockChan=LockChan,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,LockVal=LockVal,RngLim=RngLim,GamMax=GamMax,
\ dc=DC,
\ x=x,y=y,w=w,h=h,
\ omin=omin,omax=omax,
\ Show=Show,Verbosity=Verb)

Scale=2 BluMul=0.95
C_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
C=GamMac(LockChan=LockChan,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,LockVal=LockVal,RngLim=RngLim,GamMax=GamMax,
\ dc=DC,
\ x=x,y=y,w=w,h=h,
\ omin=omin,omax=omax,
\ Show=Show,Verbosity=Verb)

COORDS=GamMac(DC,x=x,y=y,w=w,h=h,Coords=True)
TOP=StackHorizontal(SHOWCOORDS?Sub(COORDS,"Coords Original"):Sub(O,"Original"),Sub(A,A_TEXT))
BOT=StackHorizontal(Sub(B,B_TEXT),Sub(C,C_TEXT))
StackVertical(TOP,BOT)
return Last

Function Sub(clip c,string tit) {StackVertical(c.BlankClip(height=20).ScriptClip("""Subtitle(RT_String("%d] %s",current_frame,tit))""",Args="tit",Local=true),c)}


Result
https://s20.postimg.cc/litiw2fel/coords_Plus0000_zpsolotwqys.png (https://postimg.cc/image/6a3lialq1/)

EDIT: The titles added above each frame include frame number.
EDIT: Script requires Grunt() (c) Gavino, for Args arg in Scriptclip [used by Function Sub()].

[StainlessS]

GamMatch() v0.00 NEW PLUGIN [based on GamMac()] :- LINK REMOVED


GamMatch(), [Gamma Matcher] A daft Idea, based upon an extraordinary Idea by VideoFred (the gent from Gent). (Daft idea and code by StainlessS).

The Idea behind the daft idea(GamMac):- http://forum.doom9.org/showthread.php?p=1774281#post1774281
Original Idea:- http://forum.doom9.org/showthread.php?t=173683

RGB Only.

Useful to correct bad color clip where there is a better color source of perhaps lower rez available.
Additional tweaking via RedMul, GrnMul and BluMul multipliers.

What it does(roughly):-
Alter bad color clip c channel minimums, maximums and averages to match dc (good color clip) by
varying Gamma

GamMatch(Clip c,clip dc,int "Scale"=2,
\ Float "RedMul"=1.0,Float "GrnMul"=1.0, Float "BluMul"=1.0,
\ Float "Th"= 0.04,Float "loTh"=Th,Float "hiTh"=Th,
\ int "RngLim"=11,Float "GamMax"=10.0,
\ int "x"=20,int "y"=20,int "w"=-20,int "h"=-20,
\ Bool "Show"=True,int "Verbosity"=2,Bool "Coords"=false
\ )

c, no default. Bad Color clip.

dc, no default. Detection clip (good color clip). Must be same ColorSpace and FrameCount as source clip, no other similarities enforced.

Scale, default 2 Range 0 -> 2.

RedMul, default 1.0 Red channel multiplier adjustment. [0.1 <= RedMul <= 10.0]
GrnMul, default 1.0 Green channel multiplier adjustment. [0.1 <= GrnMul <= 10.0]
BluMul, default 1.0 Blue channel multiplier adjustment. [0.1 <= BluMul <= 10.0]

Th, Default 0.04 Sets Default for loTh and hiTh. Suggest Default, 0.04(percent). [-1.0(OFF) , or 0.0 -> 1.0]
loTh, Default Th As for Ignore_low in AutoLevels, or Threshold in YPlaneMin. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding minimum R, G or B channel values.
-1.0 is OFF, input channel minimum is set to 0 as for levels(0,gamma,input_max, ... ).
If loTh >=0.0, then will scan frame looking for lowest pixel value whose cumulative sum
[including all pixels counts of lower value pixels] is greater than loTh%.
loTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).
hiTh, Default Th As for Ignore_high in AutoLevels, or Threshold in YPlaneMax. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding maximum R, G or B channel values.
-1.0 is OFF, input channel maximum set to 255, as in levels(input_min,gamma,255, ... ).
If hiTh >=0.0, then will scan frame looking for highest pixel value whose cumulative sum
[including all pixels counts of higher value pixels] is greater than hiTh%.
hiTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).

RngLim, default 11 [1 <= RngLim <= 32]
If ALL THREE RAW input channel ranges ie (ChannelMax(max(hiTh,0.0))-ChannelMin(max(loTh,0.0))) are less than RngLim then
all scaling is disabled, and remapping is linear without gamma estimation, to range omin -> omax,
ie avoid remapping of Black, White frames, or single color frames.

GamMax, default 10.0 Upper value for guess gamma [2.0 <= GamMax <= 10.0]
Starting guess upper range and limit for gamma estimator (probably best left alone).
The lower guess range and limit will be set to 1.0 / GamMax, by default 0.1.


x,y, Both default 20. Area of dc Detect clip frame to sample when getting averages and estimating Gamma function, allows to ignore rubbish at frame edges.
w,h, Both default -20. Specified as for crop eg x=10,y=20,w=-30,h=-40, as in crop(10,20,-30,-40).

Show, default true True, show metrics info on frame.
Verbosity, default 2 0 = Only upper frame metrics Flags line only
1 = Upper frame metrics
2 = Upper + important ones. (default)
3 = Nearly Full metrics.
4 = Full Metrics except version info
5 = Full Metrics including version info
Upper frame metrics shown as eg:- (when Verbosity=5=FULL)

nnnnn] Flags:- SR
R G B
DC: 4,255 3,255 2,255
DC_AVE: 92.123 128.543 132.890
RAW: 10,253 10,253 10,253
IN: 10,253 10,253 10,253
IN_AVE: 78.466 88.552 78.767
SCALED: 71.847 82.431 72.162
GAMMA: 1.135 1.000 1.123
OUTAVE: 82.431 82.422 82.451 <<< OUTAVE will read about same as DC_AVE (made up numbers)

where,
nnnnn, is the frame number.
Flags:- (Specific to current frame, can change frame to frame)
'S' = Scale, mode signified by color.
Greyed out. Scale = 0(No Effect). May be Greyed out if all channels Min/Max are 0,255.
White. Scale = 1[Scales input channel average maximum dynamic range of R,G,B]
Orange. Scale = 2[Scales input channel average dynamic range of R and G and B, Individually]
'R' = Limited by RngLim, mode signfied by color.
Greyed out. Not Range Limited.
Red, at least 1 channel has remapping disabled.
DC: Shows comma separated channel minimum and maximum of DC clip(dependent upon loTh, hiTh).
DC_AVE: DC Clip channel averages.
RAW: Shows RAW comma separated channel minimum and maximum, eg ChannelMin(max(loTh,0.0)) and (ChannelMax(max(hiTh,0.0)),
only shown if Verbosity>=3 or, if any RAW input range is less than RngLim AND any of the RAW inputs are different
to the equivalent standard input.
IN: Shows comma separated channel minimum and maximum (dependent upon Scale, loTh, hiTh).
IN_AVE: Input channel averages.
SCALED: Scaled input averages, (dependent upon Scale, loTh, hiTh, channel minimums and maximums).
GAMMA: Estimated gamma to achieve lockval for channel. (dependent upon pretty much everything).
OUTAVE: Output channel average ie rendered result.

DC and DC_AVE derived from DC (Good color clip), all others from clip c (BAD color clip, Incl OUTAVE).

Coords, default False. If True, then shows DC clip with dotted lines showing the x,y,w,h coords plotted on frame. (All other functionality disabled).


Simulated Demo

# Some good color clip
Avisource("1941 Flint Michigan Parade [Low, 360p].mp4.AVI")
ConvertToRGB24.KillAudio
DC=Last

# Simulate bad color, Input clip
RED=ShowRed(Pixel_Type="Y8").Levels( 0,0.9,255, 8 , 247,coring=false)
GRN=ShowGreen(Pixel_Type="Y8").Levels(0,1.5,255, 12, 223,coring=false)
BLU=ShowBlue(Pixel_Type="Y8").Levels( 0,2.5,255, 18, 239,coring=false)
MergeRGB(RED,GRN,BLU,pixel_Type="RGB24")

O=Last

Scale=2
RedMul = 1.0 # Required Ave multiplier for Red Channel, applied when requesting GuessGamma(reqAve*RedMul), Even applied when LockChan=-1.
GrnMul = 1.0 # Same for Green channel. GrnMul even applies when LockChan is Green Channel, etc for chans.
BluMul = 1.0 # Same for Blue channel. Allows tinkering/fine tuning.
Th = 0.04
RngLim = 11
GamMax = 10.0
Show = True # Metrics
Verb = 5 # Verbocity FULL

x =5 # Coords (for dc Detection Clip)
y =5
w=-5
h=-5

Scale=0
A_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
A=GamMatch(Last,DC,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,RngLim=RngLim,GamMax=GamMax,
\ x=x,y=y,w=w,h=h,
\ Show=Show,Verbosity=Verb)


Scale=1
B_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
B=GamMatch(Last,DC,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,RngLim=RngLim,GamMax=GamMax,
\ x=x,y=y,w=w,h=h,
\ Show=Show,Verbosity=Verb)

Scale=2
C_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
C=GamMatch(Last,DC,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,RngLim=RngLim,GamMax=GamMax,
\ x=x,y=y,w=w,h=h,
\ Show=Show,Verbosity=Verb)

COORDS=GamMatch(Last,DC,x=x,y=y,w=w,h=h,Coords=True)

TOP=StackHorizontal(Sub(O,"Original (Simulated bad clip)"),Sub(COORDS,"Detect with Coords"),Sub(A,A_TEXT))
BOT=StackHorizontal(Sub(DC,"DC Detect (Good color clip)"),Sub(B,B_TEXT),Sub(C,C_TEXT))
StackVertical(TOP,BOT)
return Last

Function Sub(clip c,string tit) {StackVertical(c.BlankClip(height=20).ScriptClip("""Subtitle(RT_String("%d] %s",current_frame,tit))""",Args="tit",Local=true),c)}


result

https://s20.postimg.cc/wwg279px9/Gam_Match_zpsseitomzc.png (https://postimg.cc/image/aki9dvqt5/)

without metrics

https://s20.postimg.cc/7269hhpx9/Gam_Match_No_Metrics_zpsq0t4iyq0.png (https://postimg.cc/image/e5e4x3vcp/)

EDIT: IN: Red values a little wonky in metrics.

EDIT: Both clips should be in sync.

EDIT: The Scale=0 result does not alter minimums and maximums to match DC, hence the slightly reddish white lines on road.

[super8boy]

That's seriously great work. Well done. Really impressive.
How well does it work on film for which an overscan has been done?

Would the system get confused by extra information on the top and bottom of the frame + left (perforations) and right?

If that was the case, I guess one could only process say only x by y amount of pixels (say 75% of the image) correct?
If not, the only solution would be not to overscan so much, to not overscan at all or to recrop the video to 1440x1080 for example before applying Gammac.

Trying to figure out what the best workflow would be.

[johnmeyer]

That's seriously great work. Well done. Really impressive.
How well does it work on film for which an overscan has been done?I haven't yet had the chance to use this, but for similar situations you merely create a cropped clip and use that. You can then apply the modifications to the uncropped clip, or apply the modifications to the cropped clip and then add borders. Either way, you end up with the same sized clip as the original.

[StainlessS]

You can set args x,y,w,h and coord=true, to show current coords on screen for DC detect clip. Set cords =false for use.
Cropping DC would also work fine.

[StainlessS]

Now not mobile.

The above windowed demos did not I think cope with DC detect clip of different size to source (just for the windowed display),
I have done updated scripts some time ago, but there seemed to be little interest and so did not bother to update scripts.
Also, the published GamMatch() plug, suffered from Access Violations if not given two clips (1 was supposed to be optional),
I dont know why this occurred, from examining source I think there should have been no problem, but there was. Anyway,
made second clip non optional and problem has disappeared. (I had been testing with AVS+, perhaps problem was in some way related,
it seemed to crash before getting 'into' the plugin, so perhaps something in AVS+ was accessing optional clip when not supplied).
I shall try to update GamMatch() plug, and also demo windowed routines for both GamMac() and GamMatch(), soon.

GamMac(), lets you alter Channel averages to match one of the other channels (or optional specific value), eg faded color on aged film.

GamMatch, Allows to correct a clip that has had Levels + Gamma badly applied, to one of more channels, by using an in sync version
with good un-messed with color, but perhaps of inferior resolution.
GamMatch is unlikely to be of any use where eg Tweak or some other non RGB levels type mod has been applied, it is yet though not certain
(as nobody has responded) as to whether or not a faded hi rez clip could be fixed via a non faded DC detect clip.
(Actually, Tweak does not seem to give valid ColorSpace's in v2.6 AVS docs, just tested, does not support RGB).

[StainlessS]

OK, Here modded Windowed Demo script that supports different sized DC detect clip.


Avisource("1941 Flint Michigan Parade [Low, 360p].mp4.AVI")

ConvertToRGB24.KillAudio
O=Last
DC=Last

# Test DC can be different size
DC=DC.Blur(1.0).BilinearResize(320,240) # Detection Clip Can be different size(uses source clip if dc not supplied, Denoised or whatever)

LockChan = 1 # Chan for lock to Ave, 0=R, 1=G, 2=B
# -1 = Use LockVal below.
# -2 = LockVal=(RedAve+GrnAve+BluAve)/3.0 for LockVal.
# -3 = LockVal=Median(RedAve,GrnAve,BluAve)
Scale=2
RedMul = 1.0 # Required Ave multiplier for Red Channel, applied when requesting GuessGamma(reqAve*RedMul), Even applied when LockChan=-1.
GrnMul = 1.0 # Same for Green channel. GrnMul even applies when LockChan is Green Channel, etc for chans.
BluMul = 1.0 # Same for Blue channel. Allows tinkering/fine tuning.
Th = 0.01
LockVal = 128.0 # Only valid if LockChan == -1
RngLim = 11
GamMax = 10.0
Show = True # Metrics
Verb = 4 # Verbocity FULL
SHOWCOORDS=True # Show DC detect clip instead of original

x =5 # Coords (for dc Detection Clip)
y =5
w=-5
h=-5

omin=5 # Output channels minimum
omax=250 # Output channels maximum

#Return GamMac(DC,x=x,y=y,w=w,h=h,Coords=True) # Show Coords only

Scale=0
A_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
A=O.GamMac(LockChan=LockChan,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,LockVal=LockVal,RngLim=RngLim,GamMax=GamMax,
\ dc=DC,
\ x=x,y=y,w=w,h=h,
\ omin=omin,omax=omax,
\ Show=Show,Verbosity=Verb)


Scale=1
B_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
B=O.GamMac(LockChan=LockChan,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,LockVal=LockVal,RngLim=RngLim,GamMax=GamMax,
\ dc=DC,
\ x=x,y=y,w=w,h=h,
\ omin=omin,omax=omax,
\ Show=Show,Verbosity=Verb)

Scale=2
C_TEXT = RT_String("Scale=%d rMul=%.2f gMul=%.2f bMul=%.2f",Scale,RedMul,GrnMul,BluMul)
C=O.GamMac(LockChan=LockChan,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,LockVal=LockVal,RngLim=RngLim,GamMax=GamMax,
\ dc=DC,
\ x=x,y=y,w=w,h=h,
\ omin=omin,omax=omax,
\ Show=Show,Verbosity=Verb)

COORDS=O.GamMac(dc=DC,x=x,y=y,w=w,h=h,Coords=True)
ODC=((SHOWCOORDS)?COORDS.Spline36Resize(width,Height):O) # Resize COORDS (Not necessarily the same sizse as source clip)
ODC_TEXT=(SHOWCOORDS)?"Detect Clip with Coords":"Original"

TOP=StackHorizontal(Sub(ODC,ODC_TEXT),Sub(A,A_TEXT))
BOT=StackHorizontal(Sub(B,B_TEXT),Sub(C,C_TEXT))
StackVertical(TOP,BOT)
return Last

Function Sub(clip c,string tit) {StackVertical(c.BlankClip(height=20).ScriptClip("""Subtitle(RT_String("%d] %s",current_frame,tit))""",Args="tit",Local=true),c)}


The script as above has created a dummy DC detect clip by Blurring(1.0) and BilinearResize(320,240)
[EDIT: Resize to test DC different size in window display, Blur for no particular reason other than to throw a spanner in the works]
The source clip is 490x360 in size.
Also, SHOWCOORDS=True, to show DC and not the original clip frame.
The Coords shown are relative to the downsize DC clip which was upsized again for display
to match the source clip size.
oMin and oMax set at 5 and 250 respectively (foot and head room for further tweaking).
Below, DC clip shows coords as dotted lines. Pixels outside of the dotted line coords are not considered when
processing the DC frame.
The Blur/Resize test line can be commented out.

https://s20.postimg.cc/bpgwx02nx/gmac1_zpsbq2vafkd.png (https://postimg.cc/image/qlfg4le2h/)

[StainlessS]

I guess that the nearest existing thing to GamMatch() [posted and linked a few posts earlier] is MatchHistogram() by LaTo:- http://forum.doom9.org/showthread.php?t=153196&highlight=histogram

[StainlessS]

New version GamMatch v0.02 (NOTE GamMatch, not this thread plugin, but a spinnoff from it).
See MediaFire in my sig below this post.


GamMatch(), [Gamma Matcher] An daft Idea, based upon an extraordinary Idea by VideoFred (the gent from Gent). (Daft idea and code by StainlessS).

The Idea behind the daft idea(GamMac):- http://forum.doom9.org/showthread.php?p=1774281#post1774281
Original Idea:- http://forum.doom9.org/showthread.php?t=173683

RGB Only.

Useful to correct bad color clip where there is a better color source of perhaps lower rez available.
Additional tweaking via RedMul, GrnMul and BluMul multipliers.
GamMatch, Allows to correct a clip that has had Levels + Gamma badly applied, to one of more channels, by using an in
sync version clip with good un-messed with color, but perhaps of inferior resolution.
GamMatch is unlikely to be of any use where eg Tweak or some other non RGB levels type mod has been applied.

What it does(roughly):-
Alter bad source color clip channel minimums, maximums and averages to match dc detect (good color) clip.

GamMatch(Clip c,clip dc,
\ Float "RedMul"=1.0,Float "GrnMul"=1.0, Float "BluMul"=1.0,
\ Float "Th"= 0.04,Float "loTh"=Th,Float "hiTh"=Th,
\ int "RngLim"=11,Float "GamMax"=10.0,
\ int "x"=20,int "y"=20,int "w"=-20,int "h"=-20,
\ Bool "Show"=True,int "Verbosity"=2,Bool "Coords"=false
\ )

c, no default. Bad Color source clip.

dc, no default. Detection clip (good color clip). Must be same ColorSpace and FrameCount as source clip, no other similarities enforced.

RedMul, default 1.0 Red channel multiplier adjustment. [0.1 <= RedMul <= 10.0]
GrnMul, default 1.0 Green channel multiplier adjustment. [0.1 <= GrnMul <= 10.0]
BluMul, default 1.0 Blue channel multiplier adjustment. [0.1 <= BluMul <= 10.0]

Th, Default 0.04 Sets Default for loTh and hiTh. Suggest Default, 0.04(percent). [-1.0(OFF) , or 0.0 -> 1.0]
loTh, Default Th As for Ignore_low in AutoLevels, or Threshold in YPlaneMin. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding minimum R, G or B channel values.
-1.0 is OFF, input channel minimum is set to 0 as for levels(0,gamma,input_max, ... ).
If loTh >=0.0, then will scan frame looking for lowest pixel value whose cumulative sum
[including all pixels counts of lower value pixels] is greater than loTh%.
loTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).
hiTh, Default Th As for Ignore_high in AutoLevels, or Threshold in YPlaneMax. [-1.0, or 0.0 -> 1.0]
Percent, amount of extreme pixels (eg noise) to ignore when finding maximum R, G or B channel values.
-1.0 is OFF, input channel maximum set to 255, as in levels(input_min,gamma,255, ... ).
If hiTh >=0.0, then will scan frame looking for highest pixel value whose cumulative sum
[including all pixels counts of higher value pixels] is greater than hiTh%.
hiTh, only shown in metrics if greater or equal to 0.0 ie switched ON (Always shown when Verbosity=3=FULL).

RngLim, default 11 [1 <= RngLim <= 32]
If ALL THREE RAW input channel ranges ie (ChannelMax(max(hiTh,0.0))-ChannelMin(max(loTh,0.0))) are less than RngLim then
all scaling is disabled, and remapping is linear without gamma estimation, to range omin -> omax,
ie avoid remapping of Black, White frames, or single color frames.

GamMax, default 10.0 Upper value for guess gamma [2.0 <= GamMax <= 10.0]
Starting guess upper range and limit for gamma estimator (probably best left alone).
The lower guess range and limit will be set to 1.0 / GamMax, by default 0.1.


x,y, Both default 20. Area of dc Detect clip frame to sample when getting averages and estimating Gamma function, allows to ignore rubbish at frame edges.
w,h, Both default -20. Specified as for crop eg x=10,y=20,w=-30,h=-40, as in crop(10,20,-30,-40).

Show, default true True, show metrics info on frame.
Verbosity, default 2 0 = Only upper frame metrics Flags line only
1 = Upper frame metrics
2 = Upper + important ones. (default)
3 = Nearly Full metrics.
4 = Full Metrics except version info
5 = Full Metrics including version info
Upper frame metrics shown as eg:- (when Verbosity=5=FULL)

nnnnn] Flags:- SR
R G B
DC: 0,255 0,255 0,255
DC_AVE: 110.423 98.284 97.997
RAW: 8,247 12,223 18,239
IN: 8,247 12,223 18,239
IN_AVE: 104.545 120.037 149.821
SCALED: 103.008 130.566 152.102
GAMMA: 1.099 0.659 0.495
OUTAVE: 110.416 98.282 97.986

where,
nnnnn, is the frame number.
Flags:- (Specific to current frame, can change frame to frame)
'S' = Scale, mode signified by color.
Greyed out. Scale = 0(No Effect). May be Greyed out if all channels Min/Max are 0,255.
White. Scale = 1[Scales input channel average maximum dynamic range of R,G,B]
Orange. Scale = 2[Scales input channel average dynamic range of R and G and B, Individually]
'R' = Limited by RngLim, mode signfied by color.
Greyed out. Not Range Limited.
Red, at least 1 channel has remapping disabled.
DC: Shows comma separated channel minimum and maximum of DC clip(dependent upon loTh, hiTh).
DC_AVE: DC Clip channel averages.
RAW: Shows RAW comma separated channel minimum and maximum, eg ChannelMin(max(loTh,0.0)) and (ChannelMax(max(hiTh,0.0)),
only shown if Verbosity>=3 or, if any RAW input range is less than RngLim AND any of the RAW inputs are different
to the equivalent standard input.
IN: Shows comma separated channel minimum and maximum (dependent upon Scale, loTh, hiTh).
IN_AVE: Input channel averages.
SCALED: Scaled input averages, (dependent upon Scale, loTh, hiTh, channel minimums and maximums).
GAMMA: Estimated gamma to achieve lockval for channel. (dependent upon pretty much everything).
OUTAVE: Output channel average ie rendered result.

DC and DC_AVE derived from DC (Good color clip), all others from clip c (BAD color clip, Incl OUTAVE).

Coords, default False. If True, then shows DC clip with dotted lines showing the x,y,w,h coords plotted on frame. (All other functionality disabled).


New Demo in AVS folder, copes with different sized DC clip.
Got rid of Scale argument, does not really make sense if trying to match to another clip.

No image at the moment, Photobucket seems to be having DNS problems.

EDIT: Managed to kick my way into PhotoBucket via another route
https://s20.postimg.cc/i4fxto9dp/Gammatch_v0_zps8h9khfyf.png (https://postimg.cc/image/mqc220uwp/)

EDIT: The Demo.avs

# Some good color clip
#Avisource("F:\v\StarWars.AVI")
Avisource("1941 Flint Michigan Parade [Low, 360p].mp4.AVI")
ConvertToRGB24.KillAudio

DC=Last

# Simulate bad Input clip
RED=ShowRed(Pixel_Type="Y8").Levels( 0,0.8,255, 8,247,coring=false)
GRN=ShowGreen(Pixel_Type="Y8").Levels(0,1.5,255,12,223,coring=false)
BLU=ShowBlue(Pixel_Type="Y8").Levels( 0,2.0,255,32,239,coring=false)
MergeRGB(RED,GRN,BLU,pixel_Type="RGB24")

# Simulate DC Low res clip with good color
DC=DC.Blur(1.58).Blur(1.58).Spline36Resize(320,240) # Fake change of size for detect

O=Last

RedMul = 1.0 # Required Ave multiplier for Red Channel, applied when requesting GuessGamma(reqAve*RedMul), Even applied when LockChan=-1.
GrnMul = 1.0 # Same for Green channel. GrnMul even applies when LockChan is Green Channel, etc for chans.
BluMul = 1.0 # Same for Blue channel. Allows tinkering/fine tuning.
Th = 0.04
RngLim = 11
GamMax = 10.0
Verb = 5 # Verbocity FULL
SHOWCOORDS= False

x =5 # Coords (for dc Detection Clip)
y =5
w=-5
h=-5

A_TEXT = RT_String("OUT: rMul=%.2f gMul=%.2f bMul=%.2f",RedMul,GrnMul,BluMul)
A=O.GamMatch(DC,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,RngLim=RngLim,GamMax=GamMax,
\ x=x,y=y,w=w,h=h,
\ Show=True,Verbosity=Verb)

B_TEXT = RT_String("OUT No Metrics: rMul=%.2f gMul=%.2f bMul=%.2f",RedMul,GrnMul,BluMul)
B=O.GamMatch(DC,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,RngLim=RngLim,GamMax=GamMax,
\ x=x,y=y,w=w,h=h,
\ Show=False)


COORDS=O.GamMatch(DC,x=x,y=y,w=w,h=h,Coords=True).Spline36Resize(width,Height) # Resize Coords to same as bad clip for window display
ODC=((SHOWCOORDS)?COORDS:DC).Spline36Resize(width,Height) # Resize COORDS (Not necessarily the same sizse as source clip)
ODC_TEXT=(SHOWCOORDS)?"Detect Clip with Coords":"DC Detect (Match Original to this)"

TOP=StackHorizontal(Sub(O,"Original (Simulated bad clip)"),Sub(A,A_TEXT))
BOT=StackHorizontal(Sub(ODC,ODC_TEXT),Sub(B,B_TEXT))
StackVertical(TOP,BOT)
return Last

Function Sub(clip c,string tit) {StackVertical(c.BlankClip(height=20).ScriptClip("""Subtitle(RT_String("%d] %s",current_frame,tit))""",Args="tit",Local=true),c)}

[juanitogan]

Thank you, everyone, for this incredible GamMac tool. I was doing something very similar with ImageMagick to recover overexposed scenes, but it was generally too aggressive and lacked temporal smoothing. What GamMac accomplishes is much more sane than what I had done so far. Far faster too. In fact, your results are very close to the autoleveling tool in Paint.NET (what I consider, personally, to be the gold standard in autoleveling -- you should see what Paint.NET does with GamMac's test files).

I seem to have uncovered, however, some occasional strange sensitivity in GamMac. That, or I'm just doing it wrong. GamMac does an incredible job with much of the film I'm working with... but with some scenes, however, GamMac creates a flicker where there is otherwise none. From what I can tell, GamMac appears to be too sensitive in determining the channel min and max.

Here's a link to a 7zip of 32 frames from one of the problem scenes:

https://www.dropbox.com/s/m1p2kccy3shaixk/f1a.7z?dl=0

Note the variations in brightness and values in this mosaic:

https://www.dropbox.com/s/fl42fpzctl92qvg/f1a.jpg?dl=0

In this particular case (a 1949 film), changing the lock channel from green to red stabilizes things quite a bit... but even the red channel is not stable (see frame 18 in my test frames, t003962.png, for example). I tried most of the settings GamMac has to offer but found little effect on the stability of the channel extents -- not in any automatic way, anyhow. Thus, setting Scale=0 (to use the channel averages, which are fairly stable) is the only automatic way I have found thus far to eliminate the flicker when using GamMac. Scale=0, however, seemed less effective overall than the other settings.

One point of suspicion is that the frames with heavy dirt appear to be more at risk for wild min numbers. But, then, there are other frames with wild numbers without heavy dirt. I then suspected maybe something unseen so I looked at these frames in Paint.NET with its Levels tool. Paint.NET autolevels the frames without much variance in channel values (after you strip off the borders like I do in the AVS script; set canvas size: 704 x 472, anchor middle). Furthermore, the autoleveling I was doing through ImageMagick was stable as well. Thus, this is why I suspect the procedures used to find the channel effective extents are too sensitive in GamMac (or something like that).

I've been using johnmeyer's excellent adaption of videoFred's amazing scripts. johnmeyer's script produces far less artifacts in the wake of moving objects with my source. I've added my current test version of his script below. (Ignore the autogamma stuff--it's just something I was playing with to bring out the shadows more in home movies.)

You will see that I was testing GamMac in two places: up front just after border cropping (partly to avoid an extra color conversion), and near the end just before border application.

I must say, putting it up front is a particularly bad idea because it makes all the later filters less effective. It does, however, reveal the issue I'm getting at much more vividly up front. In other words, adding GamMac after all the other filtering tames down the flickering quite a bit but, in my opinion, this is only somewhat hiding the issue and is not a fix to it.

[[[
I can't paste the script inline--too many characters for a single post--so here it is:
https://www.dropbox.com/s/85nvmy9t29el12x/ft.avs?dl=0

]]]


p.s. My source material is from films we sent to just8mm.com. I feel the quality is fair for the price but I will be more than happy to pay twice as much for a place like CinePost next time (which I hadn't yet discovered before). Just8mm didn't frame one of the reels correctly (seen in the samples here) and the source they sent me was a DV AVI -- which would have been okay except that their telecine was running at a very bizarre 19.3-19.8-ish fps. They are obviously asleep at the wheel. I wasted a few days of my life trying to pullup the video back into source frames for processing. Hint:

ffmpeg -y -i 1.avi -vf "pullup,yadif" -vsync 0 -q:v 1 f\t%06d.png

This resulted in some barely-perceptible loss in quality in the frames "pullup" couldn't identify and that "yadif" had to correct. The real trick here was "-vsync 0"... that part took forever to find versus trying to calculate a strange fps (which always led to dupe frames here and dropped frames there) and/or trying various other pullup methods.

[videoFred]

I seem to have uncovered, however, some occasional strange sensitivity in GamMac.

Hello Juanitogan and welcome to this forum :)

The flickering is caused by the dirt spots and emulsion damage on your source files. Frame 3972 for example. GamMac is detecting a lot of almost pure black pixels on this one.
You can set LoTh pretty high (above 0.40) and the flickering will be almost gone.

You can also use a precleaned clip (detect) for the GamMac analysis, for example with removedirt().

Or you can clean the clip itself, before using GamMac.

PS: You need a better transfer, there is much more detail in those films than what I see on your examples.

many greetings,
Fred.

[juanitogan]

Hi videoFred, thank you for the welcome. I'm a fan of your digitizers. Even before seeing your work, I was tempted to build my own film scanner. I just can't justify the time with how little I would likely use it. Thank you for sharing your knowledge on that.

Thank you, also, for the loTh hint. I had tested the Th setting but had only gone 2x to 3x of default, if I recall correctly. Setting an extreme loTh does indeed work as you said it would. Apparently, the default is adequate for lighter scenes, dirt or no dirt, but darker scenes like this one require greater measures to account for dirt and other variance. Makes sense. I'll work with it more next week and see where it goes.

Yes, frame 3972 is an obvious example of how dirt affects this. That is the most extreme I have and why I included it in my sample. Yet, frame 3955 appeared to be an anomaly with no visible dirt (and I had many others like 3955). Hence, my suspicions that an algorithm somewhere can maybe be improved. Furthermore, dirt or no dirt, other applications appear to do a better job finding effective extents automatically. But that's just my two cents worth and I'll leave it to others more expert in these filters to figure that out. I hope my sample may be useful for such testing.

Yeah, I need a better transfer -- why I mentioned my experience with just8mm.com -- so others know what to expect from them (and their sister sites: 8mmtodvd.com and dvdmemories.com). This was our first trial with transferring our collection and we sent a few reels to just8mm.com. We'll be trying somewhere with better equipment as budget allows. Supposedly, most of our collection is footage of architecture in Europe, post WWII, because my grandfather was a builder with marble. Not sure when we'll get to that stuff, if ever.

[johnmeyer]

Yeah, I need a better transfer -- why I mentioned my experience with just8mm.com -- so others know what to expect from them (and their sister sites: 8mmtodvd.com and dvdmemories.com). This was our first trial with transferring our collection and we sent a few reels to just8mm.com. We'll be trying somewhere with better equipment as budget allows. I suggest that you put aside an hour or two to do some researching for promotions and deals on film transfer. Until a few years ago, you are correct that there was usually a big difference between the really cheap local transfer houses; the big chains (like YesVideo, which does the Costco and Walmart transfers); and the true professional labs that use a DataCine scanner.

These high-end scanners cost well over $100,000 so the labs have to charge a lot to recover that cost. A few years ago Blackmagic acquired one of the main companies in the business, and I think they reduced the prices quite a bit. That move, coupled with the natural decline in high-end film transfer business has made many labs very eager to take business such as yours. I have very often seen deals for 8mm, Super 8, and 16mm transfers at prices not much higher than those charged by small labs using Roger Evan's MovieStuff equipment which, while good, can never equal the quality of these "ultimate" transfer units.

So, start locally in NM, and if you can't find something in-state, start looking in Los Angeles where I think you may be surprised at the pricing you can get.

[StainlessS]

You can also use a precleaned clip (detect) for the GamMac analysis, for example with removedirt().

juanitogan, dont overlook above quote from VideoFred, you could clean the DC detect clip quite aggressively and should still produce good results.
EDIT: Even a simple Blur(1.5) or similar would calm isolated noise pixels and reduce their affect on histograms and amount of correction.

[juanitogan]

Thanks for the advice all. Don't worry, though, I may not have tested loTh high enough, but I don't feel like I've overlooked much:

I've been using johnmeyer's excellent adaption of videoFred's amazing scripts. ... You will see that I was testing GamMac in two places... I must say, putting it up front is a particularly bad idea because it makes all the later filters less effective. It does, however, reveal the issue I'm getting at much more vividly up front. In other words, adding GamMac after all the other filtering tames down the flickering quite a bit...

So, yes, I'm already on top of the effects of dirt removal and such with GamMac. I also had already spent some time shopping around for a better service to get a better transfer ("twice as much" is far better than I expected to find for a wet transfer):

I will be more than happy to pay twice as much for a place like CinePost next time

I just thought there was maybe more intel I could contribute.

Thanks again, I'll keep tweaking GamMac.

[videoFred]

I have just discovered that GamMac also can be used as a deflicker filter, with LockChan -1 . The results are truly amazing!

Fred. :)

[StainlessS]

GamMac() v1.07, new version, see 1st post [Beta lifted].


v1.07, Bug fixed in GuessGamma(), previously found gamma could have been slightly nearer than result.


EDIT:

Previously implemented something like this

Function GuessGamma(clip c,float reqAveLuma,float "GamHi",Float "GamLo") { # Single Frame Clip only
Assert(c.IsYV12,"GuessGamma: Requires YV12")
gamHi = Default(GamHi,2.0) gamLo = Default(GamLo,1.0/gamHi)
Result = -1.0
ALDif=0.0001
PrevAveL = -1.0
while(GamLo < gamHi) {
gamMid = (gamLo + gamHi) / 2.0
AveL=c.Levels(0,gamMid,255,0,255,coring=false).RT_AverageLuma(0)
if(abs(AveL-PrevAveL)<=ALDif) {
Result = gamMid
gamLo = gamHi + 1.0 # Force Exit, Not getting any nearer
} else if(AveL < reqAveLuma) {
gamLo = gamMid
} else if(AveL > reqAveLuma) {
gamHi = gamMid
} else {
Result = gamMid
gamLo = gamHi + 1.0 # Force Exit, exact match
}
PrevAveL = AveL
}
Return Result
}


Now implemented something like this

Function GuessGamma(clip c,float reqAveLuma,float "GamHi",Float "GamLo") { # Single Frame Clip only
Assert(c.IsYV12,"GuessGamma: Requires YV12")
gamHi = Default(GamHi,2.0) gamLo = Default(GamLo,1.0/gamHi)
Result = -1.0
PrevAveL = -1.0
Bestgmid=GamHi
BestDif=256.0
while(GamLo < gamHi) {
gamMid = (gamLo + gamHi) / 2.0
AveL=c.Levels(0,gamMid,255,0,255,coring=false).RT_AverageLuma(0)
dif=abs(AveL-reqAveLuma)
if(dif<BestDif) {
Bestgmid=gamMid;
BestDif=dif;
}
if(abs(AveL-PrevAveL)==0.0) {
result = Bestgmid
gamLo = gamHi + 1.0 # Force Exit, Not getting any nearer
} else if(dif<0.00001 ) {
result = Bestgmid; # close enough
gamLo = gamHi + 1.0 # break
} else if(AveL>reqAveLuma) {
gamHi = gamMid
} else {
gamLo = gamMid
}
PrevAve=AveL
}
Return Result
}


EDIT: Although above is for YV12 and GamMac is for RGB.

[StainlessS]

GamMatch() v1.03, new version

v1.03, Bug fixed in GuessGamma(), previously found gamma could have been slightly nearer than result.


NOTE, prev posted GamMac update was posted in wrong folder, ie not available, corrected at MediaFire in Below sig (or also on SendSpace, again below).
See MediaFire link below in sig or SendSpace link.

[johnmeyer]

I'm late to this game, but I'm in it now.

I have to agree with everyone else: this is a pretty amazing filter.

I have a test clip I created which contains thirty-nine six-frame scenes from a big film transfer job I did a year ago. These clips are the raw capture. Normally I apply a histogram to gain the lower shadows before I feed the video to any script, but I thought it would be best to use a completely unaltered capture. Here is that clip.

Test Clip (http://www.mediafire.com/file/wdkzhv40ejn56w6/test.avi)

I tried to pick different types of issues that represent what I get when transferring old film (most of this is from the 1940s).

This is a 14.98 fps video using the DV codec. This particular DV codec (MainConcept) permits arbitrary frame rates, but still insists on setting the interlaced flag. This video is progressive, however, and you can set any script accordingly.

On about thirty of the thirty-nine scenes, the script works brilliantly. On the rest, there are some issue.

The first issue is that sometimes I get way too much contrast. Here's an example:

Input:
http://i177.photobucket.com/albums/w208/johnmeyer/Before%20Test%202_zpsre2wjgaj.png

GamMac'd
http://i177.photobucket.com/albums/w208/johnmeyer/GamMacd_zpsvcfqeyoc.jpg

I have this problem even on clips without a big chunk of brightness.

The bigger issue is that on some frames I get color that is shifted completely wrong:

Input
http://i177.photobucket.com/albums/w208/johnmeyer/Before%20Test_zpswghgkczx.png

GamMac'd
http://i177.photobucket.com/albums/w208/johnmeyer/Color%20Shift%20GamMac_zpspjwt3696.jpg

As you can see, the input clip has pretty decent color balance, but it would be nice to gain the gamma. However, GamMac turns the fireplace brick a rather unpleasant blue-green. I'm pretty sure the original was an off-white.

I guess I can play around with the various "mul" overrides, but if I have to do that, I might as well balance each scene by hand in my NLE, which is how I've been doing this for the past six years.

I've spent several hours playing around with all the variables, but haven't hit on anything that fixes either of these problems on these scenes. Even if the function can't be used in a "set it and forget it" mode, I was still hoping I could tune it for these problem scenes.

So, in summary:

1. I was hoping for something that would gain the lower (darker) part of the gamma curve, without disturbing the highlights and black point;

2. I was hoping for more consistent color correction.

I'm not complaining, and I will still be able to get lots of use out of this for certain clips.

Here is the test script I'm using. These GamMac settings are pretty close to the defaults, but I have played around with each and every variable in order to learn about the filter, and also try to get better results for the problem scenes:
O=Last
DC=Last
LockChan = -2 # Chan for lock to Ave, 0=R, 1=G, 2=B
# -1 = Use LockVal below.
# -2 = LockVal=(RedAve+GrnAve+BluAve)/3.0 for LockVal.
# -3 = LockVal=Median(RedAve,GrnAve,BluAve)
Scale=2

RedMul = 1.0 # Required Ave multiplier for Red Channel, applied when requesting GuessGamma(reqAve*RedMul), Even applied when LockChan=-1.
GrnMul = 1.0 # Same for Green channel. GrnMul even applies when LockChan is Green Channel, etc for chans.
BluMul = 1.0 # Same for Blue channel. Allows tinkering/fine tuning.

Th = 0.04
loTh = 0.04
hiTh = 0.04
LockVal = 128.0 # Only valid if LockChan == -1

RngLim = 11

GamMax = 10.0
Show = True # Metrics
Verb = 2 # Verbocity FULL
SHOWCOORDS= True # Show Original with Coords

x =20 # Coords (for dc Detection Clip)
y =20
w=-20
h=-20

omin=0 # Output channels minimum (footroom for manual editing).
omax=255 # Output channels maximum (headroom for manual editing).


source=AVISource("E:\fs.avi").KillAudio()

output=GamMac(source,LockChan=LockChan,SCALE=SCALE,RedMul=RedMul,GrnMul=GrnMul,BluMul=BluMul,
\ Th=Th,LockVal=LockVal,RngLim=RngLim,GamMax=GamMax,
\ dc=DC,loTh=loTh,hiTh=hiTh,
\ x=x,y=y,w=w,h=h,
\ omin=omin,omax=omax,
\ Show=Show,Verbosity=Verb)

#return output
#stackhorizontal(source,output)

#/*
return Interleave(
\ source
\ , output
\ )
#*/

[StainlessS]

Hi John, give it a bash with Scale=1.
Scale=2, scale primaries individually giving in those cases color shift.
There is probably a big min/max range difference between the primaries.

I'll get your test clip and some point but not just yet.

EDIT: I got your clip John, Nice test clip (and not too big), thanx.

EDIT: John, request:, can post any further SOURCE images in this thread as png, result can be jpegs, thanx.

EDIT: John, can you repost or PM both those source images as png please (and verify is GamMac v1.07).

[johnmeyer]

I have appointments this morning. Should be back at my editing computer about noon, my time (8:00 p.m. your time, I think). I'll re-post roughly the same pics (I was just copy/pasting from NLE timeline, so the only way to avoid JPEG is to go back to the source). You now have the original AVI (it was losslessly cut from the original material), so you can get to the original color and avoid the compression artifacts by using that. I don't think I included the exact frames that I used for the still shots, but you do have six frames from the same scene.

P.S. I just noticed that none of the images I posted are showing up. Photobucket must be having problems. They displayed fine last night when I previewed and then posted. I guess I'll try uploading to this site.

[johnmeyer]

OK, I changed the two "input" photos, in my post above, to PNG. The GamMac'd versions are still JPEG. Photobucket is working again this afternoon, after having been flaky the past 24 hours. Hopefully it will work for you.

[Bernardd]

Hello,

In my opinion, GamMac is a tool that allows to correct the colors according to the theory of the gray world. It seeks, in fact, the equality between the mean values of each channel.
For the images of the young children in front of the chimney, I think that the gray world theory is not adapted to this case. ColorYUV (autowhite = true) give also a green
dominant at the fireplace.

With this script, ( https://forum.doom9.org/showthread.php?p=1797799#post1797799 ) which exploits the RGBAdapt plugin, a autogain function allows you to change the colors independently of the gray world theory.
As the work is in RGB espace, this autogain reinforces light and darkness but also the colors. Its application may be a solution for scenes such as the chimney or on the beach.

Bernard

(google traduction)

[videoFred]

With this script, ( https://forum.doom9.org/showthread.php?p=1797799#post1797799 ) which exploits the RGBAdapt plugin, a autogain function allows you to change the colors independently of the gray world theory.
As the work is in RGB espace, this autogain reinforces light and darkness but also the colors. Its application may be a solution for scenes such as the chimney or on the beach.

Hello Bernard,

Can you show us a result of your script applied on these specific frames?

Fred.

[videoFred]

The first issue is that sometimes I get way too much contrast.

Hi John, this can be solved with oMin and oMax (see examples)


The bigger issue is that on some frames I get color that is shifted completely wrong

Yes, I have the same problem on some frames and I think it happens when one color is dominating.


As you can see, the input clip has pretty decent color balance, but it would be nice to gain the gamma. However, GamMac turns the fireplace brick a rather unpleasant blue-green. I'm pretty sure the original was an off-white.

On this specific frame, the red channel is dominant. When set LockChan to 0 (red) the green cast is better, but still not perfect:

http://www.super-8.be/Doom/247_test_John_Meyer000135.jpg

It needs more specific "mul" settings to be correct:

http://www.super-8.be/Doom/247_test_John_Meyer000136.jpg

I wonder if a smart guy like StainlessS can see some consistency in all these values. :confused:

Anyhow, it might be an idea to add a "auto lockchan" option. If one color is realy dominating, lockchan should lock on that color.

It's very obvious on this frame for example:

http://www.super-8.be/Doom/247_test_John_Meyer000077.jpg

But the color dominance is sometimes changing from frame to frame so I do not know if it can be done without flickering effects etc... Also, estimated gamma will be pretty high.

Fred.

[Bernardd]

Below three results of script

two first given with only gain_strength = 0.8

https://www.dropbox.com/s/ogj4emqu2jt1xl3/cheminee.png?dl=0

https://www.dropbox.com/s/cosk1qfjarhjreq/Plage.png?dl=0

the last given with default args gain_strength = 1.0, rpow_strength = 1.0 and bias_strength = 1.0

https://www.dropbox.com/s/57qzp5o4ck5jmsp/neige.png?dl=0

Bernard

[johnmeyer]

Below three results of scriptThe first two results are very, very good. The last is not good.

Do you have a list of plugins required for your script?

Hi John, this can be solved with oMin and oMax (see examples)...I thought I had tried that, but I'll go back and try again. Thanks for that help.

On this specific frame, the red channel is dominant. When set LockChan to 0 (red) the green cast is better, but still not perfect:That result looks exceptionally good. Once again, I thought I had tried that.

I don't mind too much if I have to run the script several times with different settings. I often create 2-3 versions of a given film and then line them up on the NLE timeline. I quickly scrub through the version that gives me the best result for the majority of the film, and when that fails, I switch to one of the other versions. It obviously takes more computer time, but since I can do other things while the computer cranks, it is not too much of a problem.

I'll go back and "play around" with the settings some more, now that I have these hints.

[videoFred]

I often create 2-3 versions of a given film and then line them up on the NLE timeline. I quickly scrub through the version that gives me the best result for the majority of the film, and when that fails, I switch to one of the other versions.

Yes, this is the way to go until we have a perfect all automatic script (probably impossible).
Have you ever tried ClipClop John? Another StainlessS idea and it works like a charm.

Fred.

[videoFred]

Below three results of script

I agree with John: cheminee.prg looks very, very good Bernard.

I will see if I can get your script running here.

Fred.

[Bernardd]

The script is based on StainlessS's RGBADapt plugin http://forum.doom9.org/showthread.php?t=170642
It need StainlessS's RT_Stats plugin http://forum.doom9.org/showthread.php?t=165479
It need Gavino's GRunT plugin http://forum.doom9.org/showthread.php?t=139337 and GScript plugin http://forum.doom9.org/showthread.php?t=147846
Bernard

[StainlessS]

I am chewing on it. (tis very chewy, my jaws are aching :) )

[Bernardd]

In my script, gain fonction uses channel MinMaxDiff values. In extraction process for these datas Rt_Stats has a Threshold arg
which is a percentage, stating how many percent of the pixels are allowed below minimum or above maximum.

For Rt_Stats default threshold value is 0.0, in my script default value is 0.10, but with 0.50 for snow scene the ouput is below.

https://www.dropbox.com/s/thuy67k2kqxo8pp/neige2.png?dl=0

Bernard

[johnmeyer]

Have you ever tried ClipClop John? Another StainlessS idea and it works like a charm. Fred.I am aware of it, and as he was developing it I skimmed the thread. For this particular situation, I'm not sure it would save any time compared to doing the work in my NLE (Vegas Pro) which has a built-in multi-camera capability. I can view many versions, playing all at once, and cut between them (I can even do this while playing) simply by pressing a single key on the keyboard that has been assigned to that camera. I can immediately undo anything I don't like, or can "slip" the edit point one way or the other. I can also cross-fade between cameras. This is useful in this particular situation if I want to make less obvious and less abrupt the transition between two different corrections.

[StainlessS]

For Rt_Stats default threshold value is 0.0, in my script default value is 0.10, but with 0.50 for snow scene the ouput is below.


RT_Stats Threshold and GamMac Th, (or individual set loTh, and hiTh) are pretty much the same thing. JFYI.

[videoFred]

The script is based on.......

Yes, I know. Are you sure you have posted a good working script Bernard? I'm getting GScript syntax errors on lines 82, 149, 342 and 410. Might be a copy/paste error.. Can you upload your script in one part somewhere?

Fred.

[Bernardd]

Fred,
in DropBox, script file
https://www.dropbox.com/s/yis4gwsdb0ditkf/RGBAdapt_AWB_Process.avs?dl=0
Bernard