Original subtitles

[Autogenerated] in this clip, we're going to go over the channel.

Merge operators channel merge operations are the mathematical

functions at combined two channels to give you a result.

There are many ways that we can merge channels and

operate on them through the channel.

Merge.

I have this scene that you can open up and follow along with.

We have different groupings of different operations and we're

going to start out with our first one right here.

Now, this is called ABS minus abs minus is an absolute value of a minus bi.

And what this does is it gives you the the difference of the two pixels.

So here we have a star that is made out of 20.5 gray put 5.5

point 5.5 and we have a full color white circle.

The operator has been changed to ABS minus and it gives us this result.

This result is the difference between each the absolute

value of the difference between each pixels.

Now the next operator B, if not a shows a wherever a exists.

Otherwise it shows be so.

If we have our white star on our white circle, it combines them in this way.

Now it does combine them.

However, we do get thes alias ing artifacts right here.

And that is because these air not black.

So they are pixels that exist in a so because they exist, they do show through.

Otherwise they show be so unless the values absolutely zero,

it will collect those pixels and pass them alone.

Now we have Max.

Now we have again.

We have a 0.5 star and we have a full value of a point or a 1.0 circle here.

The operation has been set to Max.

Now this basically takes the maximum value of air B.

So a comma be the max value,

so it selects the lighter of the two colors of the resulting color.

Onley areas darker than be are replaced,

while other areas air lighter than be do not change when it compares A and B,

it takes the absolute value of the maximum pixel from each area.

So you can see that because the circle is a maximum value over the darker star.

It keeps all of the circle.

But it on Lee keeps the star where it was brighter than

the black of the outline of the circle.

Thus, it keeps the maximum value.

Now, if we're gonna have a maximum, we might as well have a minimum.

But in this case, I have the star as a solid white star and a salad white circle.

And this time it's going to take the minimum value pixel from a M B.

It selects the darker of the two colors as a resulting color.

Any parts that are lighter than be are substituted.

Any parts of the image that are darker to be don't change.

So what this means is that where the overlaps?

Because there is black over here and there's white over here.

When it results, it clips that off.

Same thing with the circle on the Star side.

There's black on the circle.

There's white, so it results in a clipping of both.

So in this, it both clips the star and the circle, creating a brand new shape.

This guy's called from now from is B minus A.

I also want to point out that minus is a minus bi.

These are essentially the same note from and minus both of them,

our subtraction, and you can get this result by swapping the channels up here.

So I'm gonna hit shift acts which will reverse the inputs.

A is over here and be is here that will reverse the inputs,

and now you can see that it creates the same thing.

Now it's subtracting be for May, even though the inputs are reversed,

so divide the values but stops to negative values from becoming a positive.

So when this divides a over B,

it prevents anything less than zero from going away.

And what I have is a 00.5 star and the a full white circle on what you concezio.

It's dividing that one by itself, resulting in the same value,

or it's dividing zero and skipping it so it doesn't go below zero.

But where you end up getting is a little bit of an artifact where the

intersection of the anti liaising where different values are,

Let's look at multiply.

We've got a get the white star and a white circle,

and what ends up happening is very similar to one

of the very similar to minimum, but it's doing it differently.

Some multiply is a times B, if a is less than zero and B is less than zero.

So multiplies by a and B will always give it a darker value.

Can see that it has resulted in zero and as resulted in one now in

over here shows areas of overlap that are this Does this can allow

for values going less than zero right here.

Multiply will clamp it where in will actually just do a straight multiplication.

So in is another form of multiplication where it does not

calculate for the F A A and B are lesson zero.

Now let's take a look.

It out out is another form of multiplication,

however, inverts the Alfa Channel before it does the multiply.

So it's not doing a a Times B, its first inverting it by subtracting one by B.

So it basically inverts the circle on the B side and then multiplies,

which is why it looks like it's cut out.

Stencil is the opposite,

where it inverts the a side so it takes that star and then

inverts it by subtracting it by one,

then multiplies it by B and gives you the inverse so you can

see out in stencil are inverts of each other,

and it's almost like you can get a very similar

effect simply by swapping the inputs.

Now let's look at the last row we have plus in which we have a star,

which is a value of +1111 and we have a circle that is a value of one,

and it's a plus B.

So unlike Union, which just puts them together but keeps them at the same value,

this one actually increases their value because now

the points of the star are one.

But where Everything where things overlap, the values air now, too.

And union just is.

The default version of this you can see is 1111 everywhere.

And that's because it multiplies a Times B first and gets the

results of that and then subtracts that by the B,

basically cutting a hole out of it and then adding a together in its

results with an additional process and add process.

A plus B that results in not making the values go above one,

and then we have Zoar.

Zoar is a times B times to then subtracted by B and then added and it

shows both a MB images where they do not overlap.

So this ends up creating a really interesting

subtraction of the shape from both shape.

So basically kind of subtracts the circle from the star and the star from the

circle and then puts them together and kind of creates.

It's interesting checkerboard thing.

This file is provided to you for reference to show off all

the different types of channel operations.

And this is really how all these kind of go together.

We're going to now take what we just learned,

and we're gonna apply it to creating our own light rap in the next clip.