Introduce the computer graphics course plan and Introduction to Computer Graphics, Raster and Vector

Computer graphic is the field concerned with generating images from geometrical descriptions and deal with manipulation, and storage of digital graphical data that includes still images (two- and three-dimensional), animated graphics, and interactive images. This field is also concerned with rendering them accurately (so they look real) and fast (so that generating a long video of computer animation.
Image processing is the field that deals with methods, techniques, and algorithms for image analyzing, manipulation, enhancement, and interpolation.
A pixel (picture element) is the smallest unit of a digital image and the fundamental building block of all computer images. A pixel is a dot of light on the computer screen represented by its color code, which is have either 0/1 values (Binary image), a grayscale value (Gray image) or three components of a color( bitmap image).
A Digital image is a rectangular array of rows and columns of pixels. Early images had only black-and-white or grayscale pixels, and featured low resolutions. Current images are mostly colored, where the colors are selected from huge palettes of millions of colors. Today’s images can have resolutions of hundreds of pixels per centimeter, more often measured as dpi (dots per inch).
Vector graphics This type is older graphics displays. In a vector graphics computer system, the program running in the computer creates a picture using graphics components such as points, lines, and circles. A set of such components is stored in memory and becomes the description of an image that a visible part on the output (normally a display screen).
• Where the vector graphics file is a program saved in memory, therefore, there is need more difficult operation to display the image. It is need to run the program and display the results on screen.
• The memory storage space that required to vector graphics is low.
• The resolution of resulted image is constant for a different scales, because the scaling operation is performed on the operands of graphics not on the image file as in raster graphics.
• There is no need to analyzing the image in vector graphics because its creates in computer.
Raster graphics Most current graphics displays are of this type. The screen displays an image that consists of small dots (pixels) (not arithmetic relations). In this type, the image is store as an image file in memory . The program displays an image to the screen by translates it s saved file to colored pixels in screen. Line or circle are represented as groups of adjacent cells with the same value.
• The force of the raster graphics is its simplicity, where, the processor need to perform a simple operation to display the image from the file to screen.
• The total volume of data storage for raster graphics and handled is high.
• The raster graphics have constant accuracy, therefore, it have a low resolution with high scaling. Thus, the raster is an image file stored in memory.
• In raster graphics, analyzing process for the image is more difficult that is called image processing.
Application of computer graphics
The applications of computer graphics are many and varied; we can, however, divide them into four major areas:
1. Display of information .
2. Design (computer-aided drafting (CAD) as example of design system).
3. Simulation and animation (as in games and simulation system).
4. User interfaces (as an example the systems interfaces ).
Although many applications span two or more of these areas, the development of the field was based on separate work in each.
A computer graphics system
A computer graphics system is a computer system; as such, it must have all the components of a general-purpose computer system. Let us start with the high-level view of a graphics system, as shown in the block diagram in Figure (1). There are five major elements in our system:
1. Input devices.
2. Processor.
3. Memory.
4. Frame buffer.
5. Output (Display) devices.