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Visual computing
Computer graphics aka image synthesis
Rendering [Wiedergabe in jeglichem Sinne: 3D, 2D, Fonts, ...]
Modeling [British English: modelling]
Texturing
Animation, simulation, motion capture
Virtual Reality (i.e., games ;-) ), Augmented/Mixed Reality
Interaction, GUIs, devices
Data visualization
Image manipulation [Bildbearbeitung]
...
Image processing aka image analysis [Bildverarbeitung]
Segmentation, detection, ..., OCR, machine vision
Computer vision: "understanding" 3D scenes
Data compression [Datenreduktion und/oder -kompression]
Noise reduction, image restoration
Color management
Content-based image retrieval
Data hiding, watermarking
...
Some milestones in the history of computer graphics:
1963: Ivan Sutherland: Sketchpad (drawing with a light pen)
1975: Ed Catmull: z-Buffer (described one year earlier by Wolfgang Straßer in his PhD thesis)
1980: Turner Whitted: Ray Tracing (described 1968 by Arthur Appel)
1986: Pixar: "Luxo, Jr." (don't miss the recent continuation)
1987 to date: Pixar: RenderMan and RenderMan Interface
A look at the syllabus:
Event-based programming (standard for windows-based user interfaces)
A bit of 2D computer graphics
Image manipulation
Vector graphics
Lots of real-time 3D programming
Images and further reading: Webvision
Cornea [Hornhaut]
Iris [Iris], cf. f-stop setting [Blendeneinstellung] of a camera
Pupil [Pupille], a hole, not an actual part
Lense [Linse]
Vitreous body [Glaskörper]
Retina [Netzhaut], cf. red-eye effect on flash photographs
Optic nerve [Sehnerv]
The receptor cells (size: some mm) measure the spatial distribution of light and---somewhat limited---its spectral distribution, too
Each eye contains 100 million rod cells [Stäbchenzellen] for night vision. They can detect single photons, but produce only a grayscale image. Night vision does not constitute a mainstream topic of computer graphics
Each eye contains 6 million cone cells [Zapfenzellen] for daylight vision
Three different types for three primary colors [Grundfarben]: red (long wavelength, L type), green (medium wavelength, M type), blue (short wavelength, S type)
Blue-sensitive cones are much less abundant than the other two types (1/40 of red). Hence, it is difficult to make out details in images composed of blue and black or yellow and white or red and violet or ...
Color-to-grayscale conversion: Green contributes most, blue least. Typical weights are approximately 0.3*red + 0.6*green + 0.1*blue (Demo with Gimp).
Red-green color blindness: A genetic defect wipes out the difference between red and green cone cells (Demo with Gimp).
Additive mixing [additive Farbmischung]: Start from black and switch on lights: green + blue = cyan, blue + red = magenta, red + green = yellow (somewhat surprising), equal parts of red + green + blue = grey or white. (Demo with Gimp)
There can be a bluish green but no bluish yellow etc.
Color naming anomaly: There is no dark shade of yellow, only brown. (Demo with Gimp)
In printing, we subtract color (hence subtractive mixing) from paper white. RGB as primary colors for a printer won't allow mixing. We rather use cyan (absorbs red = long wavelengths), magenta (absorbs green), and yellow (absorbs blue). Y+M=R, Y+C=G, C+M=B (only theoretically; with existing printing colors it's violet), equal parts of C+M+Y = gray or black (only theoretically; in practice it's brownish and never becomes really dark). In practice, black is almost always used in addition to CMY. (Demo with Gimp)
Physics views color as a distribution of power over the spectrum of visible light (short/medium/long wavelengths), corresponding to MRYGCBM, the colors of the rainbow. Humans, however, think of color in terms of the color wheel [Farbkreis] with parameters such as Hue [Farbton], Saturation [Sättigung], and Brightness [Helligkeit]. There are some simple methods (such as HSV and HSL) to map these parameters to RGB and some sophisticated methods (such as Lab, which officially is called L*a*b*) that are based on precise psycho-visual experiments.
Most display devices [Anzeigegeräte] behave in a non-linear manner. RGB = (255, 255, 255) will typically be about four times as bright as RGB = (127, 127, 127). This relationship is represented through a power law [Potenzgesetz] of the form output = inputg with g ranging from 1.8 to 3.0. This g is called the "gamma value" of the display.
The color of a glowing piece of material of a certain temperature can be used as a reference for yellowish, reddish and bluish colors. In physics, temperature is measured in Kelvins (symbol K), which is degrees Centigrade [Grad Celsius] plus 273.15. Standard light bulbs have both an thermal temperature and a color temperature of about 2,000 to 3,000 K. Direct sunlight is around 6,500 K, with an overcast sky having a higher color temperature. Note that a heated material glows red, yellow and finally blue (!) with increasing temperature.
There are no receptor cells where the optic nerve connects to the retina. This "blind spot" [blinder Fleck] is hidden from consciousness. (Experiment)
Only the Fovea [gelber Fleck], a small central region of the retina, contains a large concentration of cone cells. Only here, daylight (i.e., color) vision yields sharp images. (Experiment) To compensate for that, the eye scans the focused object with small leaps (saccades). The completely sharp image that we perceive is only an illusion.
Color balance aka white balance [Weißabgleich]: Color perception adapts to the color of the light. For instance, we perceive a sheet of paper as white even when it is lit by a candle. A photograph taken without white balancing reveals the yellow tint [Farbstich].
3D vision = perception of depth: to be covered later
Visual illusions: In uncommon situations, the built-in "intelligence" of the visual system may fail. (Demonstrations) We are even blind for seemingly obvious changes in an image. (Demonstrations; see this)