COMPUTER GRAPHICS MULTIMEDIA NOTES

Flat panel displays encompass a growing number of technologies enabling video displays that are much lighter and thinner than traditional television and video displays that use cathode ray tubes, and are usually less than 100 mm (4 inches) thick. They can be divided into two general categories; volatile and static.

In many applications, specifically modern portable devices such as laptops, cellular phones, and digital cameras, whatever disadvantages exist are overcome by the portability requirements.

Volatile

Volatile displays require pixels be periodically refreshed to retain their state, even for a static image. This refresh typically occurs many times a second. If this is not done, the pixels will gradually lose their coherent state, and the image will "fade" from the screen.

Examples of volatile flat panel displays

• Plasma displays
• Liquid crystal displays (LCDs)
• Organic light-emitting diode displays (OLEDs)
• Light-emitting diode displays (LED)
• Electroluminescent displays (ELDs)
• Surface-conduction electron-emitter displays (SEDs)
• Field emission displays (FEDs) (also called Nano-emissive displays (NEDs))

Only the first five of these displays are commercially available today, though OLED displays are beginning deployment only in small sizes (mainly in cellular telephones). SEDs were promised for release in 2006, while the FEDs (also NEDs) are (as of November 2005^[update]) in the prototype stage.

Static

Static flat panel displays rely on materials whose color states are bistable. This means that the image they hold requires no energy to maintain, but instead requires energy to change. This results in a much more energy-efficient display, but with a tendency towards slow refresh rates which are undesirable in an interactive display.

Bistable flat panel displays are beginning deployment in limited applications (Cholesteric displays, manufactured by Magink, in outdoor advertising; electrophoretic displays in e-book products from Sony and iRex; anlabels).

 ==============================================================

JIF:['JPEG Interchange Format]

the file format known as 'JPEG Interchange Format' (JIF)

JPEG File Interchange Format is a minimal file format which enables JPEG bitstreams to be exchanged between a wide variety of platforms and applications. This minimal format does not include any of the advanced features found in the TIFF JPEG specification or any application specific file format. Nor should it, for the only purpose of this simplified format is to allow the exchange of JPEG compressed images.

TIFF(Tagged Image File Format (abbreviated TIFF) is a file format for storing images, popular among Apple Macintosh owners, graphic artists, the publishing industry, and both amateur and professional photographers in general. As of 2009)

=================================================================

JPEG(Joint Photographic Experts Group)

 

JPEG compression is used in a number of image file formats. JPEG is the most common image format used by digital cameras and other photographic image capture devices; along with JPEG, it is the most common format for storing and transmitting photographic images on the World Wide Web.these format variations are often not distinguished, and are simply called JPE

[An Internet media type, originally called a MIME type after MIME (Multipurpose Internet Mail Extensions]

The name "JPEG" stands for Joint Photographic Experts Group, the name of the committee that created the JPEG standard and also other standards.

JPEG is not as well suited for line drawings and other textual or iconic graphics, where the sharp contrasts between adjacent pixels cause noticeable artifacts. Such images are better saved in a lossless graphics format such as TIFF, GIF, PNG, or a raw image format.

JPEG is also not well suited to files that will undergo multiple edits, as some image quality will usually be lost each time the image is decompressed and recompressed, particularly if the image is cropped or shifted, or if encoding parameters are changed – see digital generation loss for details. To avoid this, an image that is being modified or may be modified in the future can be saved in a lossless format, and a copy exported as JPEG for distribution

The compression method is usually lossy, meaning that some original image information is lost and cannot be restored (possibly affecting image quality.) There are variations on the standard baseline JPEG that are lossless; however, these are not widely supported.

The JPEG compression algorithm is at its best on photographs and paintings of realistic scenes with smooth variations of tone and color. For web usage, where the bandwidth used by an image is important, JPEG is very popular. JPEG is also the most

CCD CAMERAS:

A charge-coupled device (CCD) is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time. Technically, CCDs are implemented as shift registers that move charge between capacitive bins in the device, with the shift allowing for the transfer of charge between bins.
The charge-coupled device was invented in 1969 at AT&T Bell Labs by Willard Boyle and George E. Smith.
======================================================================

Bézier curve :
A Bézier curve is a parametric curve frequently used in computer graphics and related fields. Generalizations of Bézier curves to higher dimensions are called Bézier surfaces, of which the Bézier triangle is a special case.
In vector graphics, Bézier curves are used to model smooth curves that can be scaled indefinitely. "Paths," as they are commonly referred to in image manipulation programs are combinations of linked Bézier curves. Paths are not bound by the limits of rasterized images and are intuitive to modify. Bézier curves are also used in animation as a tool to control motion
Bézier curves are also used in the time domain, particularly in animation and interface design, e.g., a Bézier curve can be used to specify the velocity over time of an object such as an icon moving from A to B, rather than simply moving at a fixed number of pixels per step. When animators or interface designers talk about the "physics" or "feel" of an operation, they may be referring to the particular Bézier curve used to control the velocity over time of the move in question.

Bézier curves are widely used in computer graphics to model smooth curves. As the curve is completely contained in the convex hull of its control points, the points can be graphically displayed and used to manipulate the curve intuitively. Affine transformations such as translation, and rotation can be applied on the curve by applying the respective transform on the control points of the curve.
Quadratic and cubic Bézier curves are most common; higher degree curves are more expensive to evaluate. When more complex shapes are needed, low order Bézier curves are patched together. This is commonly referred to as a "path" in programs like Adobe Illustrator or Inkscape. These poly-Bézier curves can also be seen in the SVG file format. To guarantee smoothness, the control point at which two curves meet must be on the line between the two control points on either side.

The simplest method for scan converting (rasterizing) a Bézier curve is to evaluate it at many closely spaced points and scan convert the approximating sequence of line segments. However, this does not guarantee that the rasterized output looks sufficiently smooth, because the points may be spaced too far apart.

In animation applications, such as Adobe Flash and Synfig, Bézier curves are used to outline, for example, movement. Users outline the wanted path in Bézier curves, and the application creates the needed frames for the object to move along the path. For 3D animation Bézier curves are often used to define 3D paths as well as 2D curves for keyframe interpolation.

Types Of Bezier Curves:----------->

Linear Bézier curves

Given points P₀ and P₁, a linear Bézier curve is simply a straight line between those two points. The curve is given by

B(T)=P0+t(P1-P0)

i.e. B(T)=(1-T)P0+TP1 , T->(0,1)

and is equivalent to linear interpolation.

Quadratic Bézier curves

A quadratic Bézier curve is the path traced by the function B(t), given points P₀, P₁, and P₂,

b(t)=(1-t)³P0+2(1-t)²tP1+t²P2

Cubic Bézier curves

b(t)=(1-t)³P₀+3(1-t)²tP₁+3(1-t)t²P₂+t³P₃

======================================================================

It May be content quality is not very good but i give you my very best. all the best from amit sharma

======================================================================