Pyro Industries API-1394PCI Instrukcja Użytkownika Pobierz pdf (Strona 218)

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■ STILL GRAPHICS

pictures will import so that they fill the screen from top to bottom and have black bars

on either side. Wide, horizontal, or “landscape” pictures fill the screen from side to

side with a letterbox look at top and bottom.

Color Levels and Color Space

When an image that we view is created, there are certain boundaries for the colors cre-

ated within them. You may have noticed, for example, that viewing a movie in a the-

ater is not the same as seeing the DVD at home. Aside from cheaper popcorn and Dots,

the image of a DVD on even the very best DVD projector or monitor doesn’t compare

with the vivid color that you see in the theater.

Why is this so? Because the theater uses film.

Every medium has limitations. When a DVD image is displayed, it displays an

ITU-601 image, which has approximately 2.35 million different colors. You may have

heard other numbers, but after consulting with two of the key color scientists of our

time, it turns out that the 32 million colors of RGB, when placed into an NTSC color

space, boil down to about 2.35 million colors. And although those are a lot of colors

and shades of color, they do not compare with the projection of motion picture film.

Film has around 800 million colors.

So why don’t we all put theater projectors in our homes? Well, for one thing, we

would need to rent the film from the studio, which is very costly. Most theaters make noth-

ing from ticket sales. The only money made these days is from concessions. The next time

you go to the theater, try to help them out by buying something at the concession stand.

With applications such as Adobe Photoshop, the color standard is RGB. RGB

color has around 32 million colors, so it’s not quite as good as the film variety, but

much better than ITU-601.

At this point, your head is probably spinning and you need some aspirin. Go

ahead, I’ll wait.

When you convert from Adobe Photoshop to Free DV or Xpress Pro, levels have

to be monitored and remapped from RGB color to ITU-601. All the math of remapping

Figure 6.5 A horizontal image with main-

tained aspect ratio

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Pyro Industries API-1394PCI Instrukcja Użytkownika Strona 218