Layer Blending mode study (partial)

Change only Bright (lighten)

The formula is: Max (A, B)

It's just a big brightness, nothing to say.

Top floor	Underlying	After mixing
#50 50 50	#9f BE 1c	#9f be 50

From this example, it can be seen that the algorithm is a separate operation for each channel

Masking (color filter)

The formula is: 255-comp (a) *comp (b)/255

It is because the red part is always less than 1, so the minuend will be less than comp (b), so the Cmop (b*) is the equivalent of becoming smaller, thus b* become larger and brighter.

Top floor	Underlying	After mixing
80 80 80	154 185 24	186 207 96

255-175*101/255

Ans =

185.6863

255-175*70/255

Ans =

206.9608

x=0:255;

Y= (255-x). * (255-100)/255;

Plot (x, Y, ' R ')

On

Plot (x,255-y, ' B ')

Axis ([0 255 0 255])

Grid on

Look at the blue part, set the original for the bottom of 100, when top layer is 0 o'clock the top layer of the complement is 255, at this time B*=255-comp (b), the equivalent of no change, and when top layer is 255 when the top of the time-out 0, at this time b*=255 equivalent to achieve great.

Dodge (Color Dodge)

The formula is: A+a*b/comp (b)

The odd thing about this formula is that the coefficient of addend is a, and the reason for this is that the difference in brightness varies from one pixel to another, and the feeling is richer.

x=0:255;

Y=100+100*x./(255-x);

Plot (x, y)

Axis ([0 255 0 255])

Grid on

Add (Linear simple)

Formula: A+b

This is nothing to say, more simple than the filter, the same color as the Dodge can not be pulled out of the rhythm.

x=0:255;

Y=100+x;

Plot (x, y)

Axis ([0 255 0 255])

Grid on

formulas for various blending modes (collected from the network)

Layer Blending mode study (partial)