Color Models - Additive (RGB) / Subtractive (CMYK)
Color Palettes
Dithering
Image
Compression. This is more detail that is needed for the class. Look
at the parts that you find interesting.
JPG,
GIF & PNG notes Very interesting and easy to read. Please read.
How BMPs
work
Bitmaps Vs. Vectors
Cartesian Coordinates - X,Y or X,Y,Z
Data Compression:
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Remove Repetition such as in RLE
(Run Length Encoding). This is a lossless compression scheme.
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Averaging. This is lossy.
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Range Reduction. Using less bits. Lossy as well.
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Selective Compression
BMP - Bitmaps
GIF (Lossless) - Graphics Interchange Format
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Flat, limited colors, good for cartoon and illustrations
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Not good for real world images, or images of more than 256
colors.
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87
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89a
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Can be Interlaced
PNG - Portable Network Graphics
JPG (Lossy) - Joint Photographics Experts Group
The human eye is less sensitive to saturation changes.
Example
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24 bit color.
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Photographs and images of mixed color patterns. Not good for
cartoons or text.
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Averaging a pixel grid, say 8x8 for example. Find the average
color for the grid and then store the differences for the pixels.
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Basically it tricks the eye by using less information for the
image in hopes the user can not tell. Less quality, means a poor image.
Higher quality, less compression, the user sees a good scene.
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Can be Progressive or baseline (top to bottom)
3D
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You give objects perspective to make them appear more
realistic. Make a 2D image look like a 3D image.
3D accelerator cards help render graphics without needing the CPU
to do much work. 3D scene info can go to the video card in it's raw
form.
PCI
Express replaced
AGP
(accelerated graphics port) for video cards.
Frame Rate. software and video card effect the frame rate. slow
rate appear choppy. Some 3D cards don't support some functions so their
frame rates are highter.
Refresh Rate affect the viewability of the screen.
Stages of 3D
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Modeling - Most 3D applications come with ready made objects.
Drawing the shapes and objects the make up a scene. Ways of making 3D
shapes
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Extrude - stretch
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Lathe - draw outline and rotate.
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Animation - Defining the object's motion
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Rendering - Giving the objects surfaces and lighting effects.
Can take seconds to hours depending on the quality and complexity.
Toy Story's movie took up to 3 hours for every frame of animation.
Shading - paints darker colors on distant objects that are further
than the light source.
Raytracing - the tracing of light from it's source and follows it's
path. Very slow to render, but shows a high accuracy of lighting.
Polygons -
geometric figures by drawing lines beween 3 or more points.
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Flat - single color
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Gouraud - blended colors
Z-buffer -
draws only the pixels that are visible in the scene.
Bump-Mapping - Illusion of depth in textures without increasing the
polygon count.
Output file. Export for work to a file that is viewable by others.
Such as a still image, or a video clip. You can even export as 3D file
formats that are able to be imported to another application. Such as 3D
Studio or AutoDesk. VRML (WRL extension) are also compatible. Be sure
to save your work in the native file format of your editor so you can
edit your files later.
You can use 3D for feedback as animated 3D buttons. Also you can
use 3D programs to make animated GIFs for your web site.
Keyframes & Tweening
Effects in editing:
Motion Blur - makes it appear are if things are moving
Depth of Field Rendering - simulates a camera moving into a scene.
Things change focus as the camera goes from foreground to background.
Special Effects plugins
Wireframe and Solid views
Inverse Kinematics - helps make figures joint's move.
Interesting Links:
http://freespace.virgin.net/hugo.elias/graphics/x_main.htm