Comprehensive Guide to Graphics, 3D Modeling, and Multimedia Elements

What is scaling in graphics?

Stretching or shrinking objects along the x-axis or y-axis.

What is the formula for scaling an object?

(x', y') = (sx·x, sy·y)

What does the rotation transformation do?

Rotates an object by a specified angle.

What are the formulas for rotating an object?

x' = x·cos(θ) - y·sin(θ) and y' = x·sin(θ) + y·cos(θ)

What effect does shearing have on objects?

Causes deformation of objects.

What is the formula for shearing?

x' = x + sx·y and y' = y + sy·x

What does translation do in graphics?

Shifts the object by a specified distance.

What is the formula for translation?

(x', y') = (x + dx, y + dy)

What is double buffering in graphics?

A technique to prevent flickering by writing to a virtual buffer before displaying.

What is the first step in the animation process?

The object must be drawn.

What is the purpose of tracking in composed movements?

To track the position of corresponding objects and adjust the origin of rotation.

What is the definition of a vertex in 3D modeling?

A point in 3D space.

What is a face in 3D modeling?

A flat surface bounded by edges.

What are the components of basic 3D shapes?

Vertices, edges, and faces.

What is a cylinder in 3D graphics?

A shape with a circular base and uniform height.

What is a cone in 3D graphics?

A shape with a circular base that tapers to a point.

What is a cube in 3D graphics?

A shape with 6 square faces.

What is a sphere in 3D graphics?

A shape where all points are equidistant from the center.

What is a pyramid in 3D graphics?

A shape with a polygonal base and triangular faces meeting at an apex.

What is a prism in 3D graphics?

A shape with two parallel bases and rectangular faces.

What is the purpose of 3D laser scanners?

To provide detailed surface geometry for modeling.

What is the significance of viewer's position in 3D modeling?

It defines the field of view, viewing angle, and distance from objects.

What are the key characteristics to define for light sources in 3D modeling?

Color of light and direction.

What is the purpose of defining visible and hidden objects in a 3D world?

To determine which objects are rendered based on the viewer's perspective.

What is considered a 3D object?

Any subset of space ℝ³, including points, edges, or planes.

What should be avoided in 3D modeling?

Isolated or dangling edges, isolated faces, extra edges, and extra faces.

What is more important in 3D modeling, surface or points?

The surface is important, not just the set of points occupied by the object.

What is tessellation in 3D modeling?

Approximation by polygons, usually triangles, to simplify computations.

What is the triangle advantage in 3D modeling?

Any polygon can be partitioned into triangles, allowing flexibility in modeling.

How are the orientation of triangles determined?

Vertices are listed in counterclockwise order when viewed from outside the object.

What is the benefit of determining triangle orientation?

It speeds up rendering and allows ignoring surfaces not pointing to the viewer.

What are voxels in 3D modeling?

3D building blocks that partition space into a grid of small, equisized cubes.

What are the computational costs associated with voxels?

Enormous memory and time requirements, as 3D data can be significantly larger than 2D.

What are some applications of voxel modeling?

Tomography data, medical imaging (CT scans, MRI), and volumetric data visualization.

What is multimedia?

A combination of text, images, sound, video, and animation.

What are the core elements of multimedia?

Text, images and graphics, sound, video, and animation.

What is plain text?

Fixed-sized characters from a limited character set using ASCII.

What is formatted text?

Text that uses control characters to change appearance, such as bold or italics.

What is hypertext?

Text that links multiple documents and allows non-sequential navigation.

What is ASCII?

A 7-bit binary code representing characters, including alphanumeric and control characters.

What is the purpose of text compression?

To reduce file size during storage, requiring a reverse algorithm for decompression.

What is Huffman coding?

A method for text compression that uses variable-length code words based on character frequency.

What is Lempel-Ziv coding?

A string-based approach for text compression that uses a table of possible words.

What does Unicode provide?

A universal character coding scheme for consistent encoding of multilingual text.

What is the capacity of Unicode?

It encodes more than 1 million characters, far exceeding ASCII's capability.

What are glyphs in relation to characters?

Shapes that characters can have when displayed.

What is the significance of triangle vertices in rendering?

Counterclockwise vertices indicate viewable surfaces, while clockwise indicates hidden surfaces.

What is the primary use of multimedia in education?

To enhance learning through multisensory perceptions and interactive elements.

What is one application of multimedia in tourism?

Marketing packaged tours and providing virtual tours to prospective customers.

What is the role of multimedia in corporate presentations?

To emphasize salient features and activities related to products and business partners.

What is Lempel-Ziv-Welch (LZW) coding?

A variation of the Lempel-Ziv algorithm that builds a dictionary dynamically by the encoder and decoder.

What are common uses of LZW coding?

Used in word processing packages, spell checking, and compression.

What is a TXT file?

An unformatted text document created by editors like Notepad, allowing cross-platform transfer.

What does RTF stand for and what is its purpose?

Rich Text Format; developed by Microsoft for cross-platform document exchange.

What is the DOC file format?

Microsoft's native format for Word, offering a rich set of formatting capabilities.

What does PDF stand for and what is its main feature?

Portable Document Format; developed by Adobe for cross-platform document exchange.

What is PostScript (PS)?

A page description language used mainly for desktop publishing, providing accurate display on output devices.

What is the difference between hard copy and soft copy images?

Hard copy is printed on solid surfaces, while soft copy is in electronic form.

What are continuous tone images?

Photographs with a large number of varying tones and full color range.

What defines half-tone images?

Images that display a subset of total colors due to device limitations.

What are bitonal images?

Images consisting of only two colors, typically black and white, with no shades of grey.

What are the three factors that determine color perception?

Nature of light, human vision, and interaction of light with matter.

What is the visible spectrum?

The small range of electromagnetic radiation that causes light sensations in the eyes.

What is the refraction index (RI)?

The ratio of the speed of light in vacuum to the speed in a material.

What is the RGB color model?

An additive color model using primary colors Red, Green, and Blue to describe colored lights.

What happens when all three primary colors in the RGB model are at full intensity?

The result is white.

What is a scanner used for?

To convert analog images to digital form.

What is the function of CCD sensors in a scanner?

They convert light energy to voltage pulses.

What is quantization in the scanning process?

The representation of voltage pulses as binary numbers by the ADC.

What is a flatbed scanner?

The most common type of scanner for office environments, using a glass panel for document placement.

What distinguishes a drum scanner from a flatbed scanner?

A drum scanner offers professional quality scans and better performance.

What is the purpose of a barcode scanner?

To read machine-readable visual information encoded in barcodes.

What is the role of a digital camera's LCD screen?

Used as a viewfinder for composition and adjustment, and to view stored images.

What does JPEG format refer to?

A lossy compression format used to reduce file size in digital images.

What is the significance of device dependency in color models?

Different devices produce slightly different color sets, leading to variations in color representation.

What is 'gamut' in the context of color models?

The total range of colors supported by a color model, which varies between models.

What is TWAIN?

A software protocol regulating information flow between applications and imaging devices.

Who developed TWAIN?

Hewlett-Packard, Kodak, Aldus, Logitech, and Caere.

What year was TWAIN first released?

1992.

What platforms does TWAIN support?

Microsoft Windows and Apple Macintosh.

What is the function of the TWAIN Working Group?

A non-profit organization that manages TWAIN and includes imaging vendors.

What is ISIS?

Image and Scanner Interface Specification, developed by Pixel Translations.

What is a key characteristic of ISIS compared to TWAIN?

ISIS has a wider feature set and uses SCSI-2 interface instead of USB.

How many certified scanner models are available for ISIS?

Over 250 certified scanner models.

What is BMP?

Bitmap, a standard Windows compatible format that supports RGB, Indexed Color, and Greyscale.

What does BMP not support?

Alpha channels.

What type of compression does JPEG use?

Lossy compression.

What is a key use of JPEG files?

Commonly used for photographs and continuous-tone images.

What is the maximum color support for GIF?

Maximum of 256 colors.

What type of compression does GIF use?

Lossless compression.

What is TIFF designed for?

Exchanging files between applications and platforms.

What is a key feature of PNG?

Developed as a patent-free alternative to GIF with lossless compression.

What is PICT primarily used for?

Widely used in Mac OS for graphics and page-layout applications.

What type of images does TGA support?

Supports 24-bit RGB images.

What is the primary use of TGA files?

Used in video and animation work.

What is the main advantage of PNG over GIF?

Better compression and supports millions of colors.

What is the main disadvantage of PNG compared to GIF?

PNG does not support animation.

What is the default file format for Adobe Photoshop?

PSD (Photoshop Document)

What features does the PSD format preserve?

Layers, Masks, Channels, Effects

What are the four transformation types in graphics?

Scaling, Rotation, Shearing, Translation