WWDC2017 Session 821

Transcript

>> Hi everyone.
Today we're going to talk about
something very colorful.
Display P3 and Wide Gamut, what
that is and how we use it.
But first I want to mention
color management real quick.
With color management we make
sure that the display colors as
accurately as possible across
devices, platforms, and color
spaces.
And color management is built
into both Mac OS and iOS.
And color management helps avoid
a situation like this where
colors are incorrectly
represented going from source to
device.
So as a designer makes sure to
tag your assets properly to
allow for color management to
accurately display your colors.
So what is then Display P3?
Very simply put it's a color
space within the RGB color model
that represents a larger
spectrum of colors than the
current industry standard sRGB.
And most of us have been using
sRGB for probably over a decade
now, but with display P3 we get
a 25 percent larger color space
compared to sRGB.
This means that they can
represent more colors with
better accuracy and stay more
true to what those colors
actually look like in real life.
And in this image the black
strobe represents the size of
the sRGB color space and as you
can see the Display P3 extends
way beyond that.
And when the color space is
larger than sRGB it is
informally referred to as a wide
gamut color space, also displays
supporting a larger color space
than sRGB referred to as wide
gamut displays.
And the late 2015 iMac Retina
was the first consumer-facing
computer that supported Display
P3.
When working with the Display P3
color profile you have the
opportunity to also use a larger
color depth.
16 bit per channel instead of
the usual 8.
That allows you to represent
more colors within the wide
gamut, which is especially
useful for gradients.
So let's take a look at an
example of that.
Now this is a somewhat
exaggerated example, but clearly
we have banding happening in
this sRGB gradient.
Something i could try to get run
by using dithering.
And it will look something like
this.
Or if I instead use Display
P3and set my color depth to 16
bits per channel, then banding
is then much less visible.
We're simply closing the gap
between each defined color,
giving us a much better result.
And we chose to display P3 for
its similarities to our existing
view and conditions that were
already defined in sRGB.
Then by lining both the gamut
and the wide points, we get a
color space that behaves very
similar, making the threshold to
understand again working with
Display P3 much lower.
But before we move on I want to
mention that since we're looking
at this presentation on sRGB
based projection system, all of
the examples in this
presentation are renditions,
which then leads me to who can
actually see Display P3 Images?
Well users needs a wide gamut
display that supports the
Display P3 color space and color
profile.
And Apple has supported wide
gamut displays since the late
2015 iMac Retina.
But now there's a wider range of
devices that all support Display
P3 -- for example, the iPhone 7,
the MacBook Pro with a Touch Bar
and also the iPad Pro.
But what about you as a
designer?
Because you do not want to be
flying blind when creating
Display P3 assets.
You want full control over your
colors.
So make sure to work on a wide
gamut display that supports
Display P3 like the MacBook Pro
of the Touch Bar, the iMac
Retina, or the LG5K Display.
So now we know what display P3
is and how we can see it.
Let's take a look at an example.
In this beautiful image we have
some really nice colors.
Some with wide ranges of red,
green, and orange.
Now this is an sRGB image to
current standard.
But because of the limitations
within sRGB, not all colors that
were captured by the camera are
in this photo.
Represented here by these light
blue fields.
Simply because these colors were
not available in the sRGB color
space.
The display P3 version of the
same image is a completely
different story.
Now we have rich, beautiful, and
bold colors throughout the
entire image.
And if you compare the three
images we have a pretty
significant difference and I
almost feel a little bit sad for
out buddy here on the left.
He looks really bad right now.
OK, so let's take a look at the
Display P3 Workflow and we're
going to be using Photoshop.
And let's begin with a brand new
document, and in order to take
full advantage of all of the
colors available in the Display
P3 Color Space, the first thing
you need to do is to tag your
asset with the correct color
profile.
So I'm creating that new
document in Photoshop, make sure
to set your color profile to
Display P3 like this.
And the next thing I want to do
is to change the color depth
from 8 to 16 bits per channel
like this.
And once you're finished with
you're absolutely fantastic
design, it is now time to save
out your artwork.
And there are multiple ways of
doing so on Photoshop like using
Generator or Export As.
But in this case it is key then
to use Save As and PNG as your
format because this is the only
way at the moment to both imbed
a color profile and maintain the
color depth without -- in the
exported asset.
For example, Generator will not
imbed a color profile and leave
your asset entirely untagged.
So only use Save As.
When opening raw files in
Photoshop, make sure to tag --
to change the color profile to
display P3 and the color depth
to 16 bits per channel by
clicking here.
Also, if you're receiving assets
from someone else, makes sure
that those assets are converted
to display P3 directly from the
raw file and not sRGB as the
color information would then
already be completely lost.
So walk down your asset pipeline
and make sure you get Display P3
assets directly from your
source.
If you're working from an
existing asset like an app icon,
make sure to use Convert to
Profile.
This will actually perform a
color match operation and not
alter your design.
Click like that.
And do not use Assign to Profile
as that will take your existing
colors and stretch those out
into the new color space
changing your design in some
way.
So always use Convert to
profile.
As an example let's look what
happens to the RGB of values
before and after converting to
display P3 from an sRGB
Gradient.
And we're going to look at the
red color spefically here.
Now in this sRGB image you can
see that I'll all the way up in
the top right corner and our RGB
values are then 255, 0, 0.
That's pretty much as red as it
gets.
But after converting to display
P3 I can now see that I have a
lot more red to work with and I
can also see that my RGB values
has now changed.
So you guys are now ready to go
and create stunning Display P3
Assets for your app.
But before you do take a second
and ask the question, should I?
Display P3 works great in some
cases, in others it's just not
the right choice.
For example, if your app is
designed with a calm,
de-saturated color scheme, it
doesn't use a lot of imagery,
display P3 might not be the
right choice for you.
But it is great for calling
attention to certain details
within your UI, such like a VU
meter or the red line in the rev
counter.
Or used to smooth out that app
icon gradient.
Or if your app uses a lot of
scenic imagery of nature,
landscapes, or travel
destinations, this use of
Display P3 makes a whole lot of
sense because these images will
look more vibrant and richer and
colors will stay more true to
what they actually looked like
when the camera captured that
very specific and special image.
Or for apps that feature
textiles or garments were shown
the true color of a dress or a
pair of pants is immensely
important.
So in conclusion, we have the
Display P3 color space and color
profile.
It is 25 percent larger than
sRGB and lots of your users
already have compatible devices
in their hands today.
Then keep in mind the special
workflow when creating these
assets and make sure to use it
where it makes sense.
Thank you.
[ Applause ]