In a raster scan system, the electron beam scans across rows of the screen from top to bottom, turning intensity on and off to illuminate spots and form an image. The image definition is stored in a refresh buffer memory that holds intensity values for screen points. In a random scan system, an application and graphics package are stored in memory, and graphics commands are translated into a display file that a display processor accesses to refresh the screen. Graphics patterns are drawn by directing the electron beam along picture lines one at a time, positioning it between coordinate-defined endpoints to fill each line.
The document describes the components and operation of a raster scan graphics display system. A video controller accesses a frame buffer in system memory to refresh the screen. It performs operations like retrieving pixel intensities from different memory areas and using two frame buffers to allow refreshing one screen while filling the other for animation. A raster scan display processor can digitize graphics into pixel intensities for storage in the frame buffer to offload this processing from the CPU.
Video monitors use cathode ray tubes to display output. In a cathode ray tube, an electron gun fires a beam of electrons that is focused and deflected to hit phosphor on the screen, causing it to glow. The beam rapidly redraws the image to keep the screen illuminated, in a process called refresh. Key components of the electron gun include a heated cathode that emits electrons, an accelerating anode that speeds up the electrons, and control and focusing systems that shape the beam. When electrons hit phosphor, their energy causes the phosphor to glow briefly.
Visible surface detection in computer graphicanku2266
Visible surface detection aims to determine which parts of 3D objects are visible and which are obscured. There are two main approaches: object space methods compare objects' positions to determine visibility, while image space methods process surfaces one pixel at a time to determine visibility based on depth. Depth-buffer and A-buffer methods are common image space techniques that use depth testing to handle occlusion.
Polygon is a figure having many slides. It may be represented as a number of line segments end to end to form a closed figure.
The line segments which form the boundary of the polygon are called edges or slides of the polygon.
The end of the side is called the polygon vertices.
Triangle is the most simple form of polygon having three side and three vertices.
The polygon may be of any shape.
Random scan displays and raster scan displaysSomya Bagai
Raster scan displays work by sweeping an electron beam across the screen in horizontal lines from top to bottom. As the beam moves, its intensity is turned on and off to illuminate pixels and form an image. The pixel values are stored in and retrieved from a refresh buffer or frame buffer. Random scan displays draw images using geometric primitives like points and lines based on mathematical equations, directing the electron beam only where needed. Raster scans have higher resolution but jagged lines, while random scans produce smooth lines but cannot display complex images. Both use a video controller and frame buffer in memory to control the display process.
This slide contain description about the line, circle and ellipse drawing algorithm in computer graphics. It also deals with the filled area primitive.
In a raster scan system, the electron beam scans across rows of the screen from top to bottom, turning intensity on and off to illuminate spots and form an image. The image definition is stored in a refresh buffer memory that holds intensity values for screen points. In a random scan system, an application and graphics package are stored in memory, and graphics commands are translated into a display file that a display processor accesses to refresh the screen. Graphics patterns are drawn by directing the electron beam along picture lines one at a time, positioning it between coordinate-defined endpoints to fill each line.
The document describes the components and operation of a raster scan graphics display system. A video controller accesses a frame buffer in system memory to refresh the screen. It performs operations like retrieving pixel intensities from different memory areas and using two frame buffers to allow refreshing one screen while filling the other for animation. A raster scan display processor can digitize graphics into pixel intensities for storage in the frame buffer to offload this processing from the CPU.
Video monitors use cathode ray tubes to display output. In a cathode ray tube, an electron gun fires a beam of electrons that is focused and deflected to hit phosphor on the screen, causing it to glow. The beam rapidly redraws the image to keep the screen illuminated, in a process called refresh. Key components of the electron gun include a heated cathode that emits electrons, an accelerating anode that speeds up the electrons, and control and focusing systems that shape the beam. When electrons hit phosphor, their energy causes the phosphor to glow briefly.
Visible surface detection in computer graphicanku2266
Visible surface detection aims to determine which parts of 3D objects are visible and which are obscured. There are two main approaches: object space methods compare objects' positions to determine visibility, while image space methods process surfaces one pixel at a time to determine visibility based on depth. Depth-buffer and A-buffer methods are common image space techniques that use depth testing to handle occlusion.
Polygon is a figure having many slides. It may be represented as a number of line segments end to end to form a closed figure.
The line segments which form the boundary of the polygon are called edges or slides of the polygon.
The end of the side is called the polygon vertices.
Triangle is the most simple form of polygon having three side and three vertices.
The polygon may be of any shape.
Random scan displays and raster scan displaysSomya Bagai
Raster scan displays work by sweeping an electron beam across the screen in horizontal lines from top to bottom. As the beam moves, its intensity is turned on and off to illuminate pixels and form an image. The pixel values are stored in and retrieved from a refresh buffer or frame buffer. Random scan displays draw images using geometric primitives like points and lines based on mathematical equations, directing the electron beam only where needed. Raster scans have higher resolution but jagged lines, while random scans produce smooth lines but cannot display complex images. Both use a video controller and frame buffer in memory to control the display process.
This slide contain description about the line, circle and ellipse drawing algorithm in computer graphics. It also deals with the filled area primitive.
This document discusses line attributes in computer graphics, including line type (solid, dashed, dotted), width, caps (butt, round, projecting square), joins (miter, round, bevel), and color. It describes how to set these attributes using functions like setLinetype(), setLinewidthscaleFactor(), and setPolylineColourIndex(). Lines can also be displayed using pen or brush options which have properties like shape, size, and patterns.
Raster scan displays work by sweeping an electron beam across the screen one row at a time, turning the beam on and off to illuminate spots and form an image. The intensity values for each screen point are stored in a refresh buffer and then retrieved to paint the image on the screen. Refresh rates are typically 60-80 frames per second. Random scan displays draw images using geometric primitives and store picture definitions as drawing commands in a refresh display file. Color CRT monitors use either beam penetration or a shadow mask method to display color images by emitting light from red, green, and blue phosphor dots.
This document discusses various 3D transformations including translation, rotation, scaling, reflection, and shearing. It provides the transformation matrices for each type of 3D transformation. It also discusses combining multiple transformations through composite transformations by multiplying the matrices in sequence from right to left.
This document discusses 2D geometric transformations including translation, rotation, and scaling. It provides the mathematical definitions and matrix representations for each transformation. Translation moves an object along a straight path, rotation moves it along a circular path, and scaling changes its size. All transformations can be represented by 3x3 matrices using homogeneous coordinates to allow combinations of multiple transformations. The inverse of each transformation matrix is also defined.
The A-buffer method is an extension of the depth-buffer method that allows for anti-aliasing and transparency. It works by building a pixel mask for each polygon fragment and determining the visible areas to average color values. The key data structure is the accumulation buffer, which stores color, opacity, depth, coverage, and other data for each pixel. It operates similar to a depth buffer but also considers opacity to determine the final pixel color.
This document provides an overview of computer graphics and its applications. It discusses various types of video display devices used in computer graphics like CRTs and flat panel displays. It describes how raster scan and random scan systems work and lists common input and output devices. The document outlines different chapters that will cover topics like line and curve generation algorithms, transformations, 3D viewing, surface detection, and modeling techniques. It provides examples of how computer graphics is used in fields like CAD, presentations, entertainment, education, visualization, image processing, and graphical user interfaces.
The document describes various types of computer display devices and their characteristics. It discusses raster and random scan displays, CRT monitors, color CRT technologies including beam penetration and shadow mask methods, and other display types such as direct view storage tubes. Input devices are also covered, including keyboards, mice, digitizers, and touch screens.
The document discusses the 2D viewing pipeline. It describes how a 3D world coordinate scene is constructed and then transformed through a series of steps to 2D device coordinates that can be displayed. These steps include converting to viewing coordinates using a window-to-viewport transformation, then mapping to normalized and finally device coordinates. It also covers techniques for clipping objects and lines that fall outside the viewing window including Cohen-Sutherland line clipping and Sutherland-Hodgeman polygon clipping.
This document discusses various attributes that can be used to modify the appearance of graphical primitives like lines and curves when displaying them, including line type (solid, dashed, dotted), width, color, fill style (hollow, solid, patterned), and fill color/pattern. It describes how these attributes are specified in applications and how different rendering techniques like rasterization can be used to display primitives with various attribute settings.
it is a Visible surface detection method is also known as depth buffer method. In this method detect the visible surface by using the distance of the object from the projections plane.
The depth buffer method is used to determine visibility in 3D graphics by testing the depth (z-coordinate) of each surface to determine the closest visible surface. It involves using two buffers - a depth buffer to store the depth values and a frame buffer to store color values. For each pixel, the depth value is calculated and compared to the existing value in the depth buffer, and if closer the color and depth values are updated in the respective buffers. This method is implemented efficiently in hardware and processes surfaces one at a time in any order.
The document discusses line drawing algorithms in computer graphics. It defines a line segment and provides equations to determine the slope and y-intercept of a line given two endpoints. It then introduces the Digital Differential Analyzer (DDA) algorithm, an incremental scan conversion method that calculates the next point on the line based on the previous point's coordinates and the line's slope. The algorithm involves less floating point computation than directly using the line equation at each step. An example demonstrates applying DDA to scan convert a line between two points. Limitations of DDA include the processing costs of rounding and floating point arithmetic as well as accumulated round-off error over long line segments.
Polygon clipping involves taking a polygon and clipping it against another shape to produce one or more smaller polygons. The Sutherland-Hodgman algorithm handles polygon clipping by testing each edge of the clipping polygon against each edge of the clip shape. There are four cases for how an edge can be clipped - wholly inside, exit, wholly outside, enter - and the algorithm saves or discards vertices based on these cases. Repeatedly clipping against each edge of the clip shape handles all cases and produces the final clipped polygon(s).
2D transformations are important operations in computer graphics that allow modifying the position, size, and orientation of objects in a 2D plane. There are several types of 2D transformations including translation, rotation, scaling, and more. Transformations are represented using matrix math for efficient application of sequential transformations. Key techniques include homogeneous coordinates to allow different types of transformations to be combined into a single matrix operation.
with today's advanced technology like photoshop, paint etc. we need to understand some basic concepts like how they are cropping the image , tilt the image etc.
In our presentation you will find basic introduction of 2D transformation.
The document discusses window to viewport transformation. It defines a window as a world coordinate area selected for display and a viewport as a rectangular region of the screen selected for displaying objects. Window to viewport mapping requires transforming coordinates from the window to the viewport. This involves translation, scaling and another translation. Steps include translating the window to the origin, resizing it based on the viewport size, and translating it to the viewport position. An example transforms a sample window to a viewport through these three steps.
Comprehensive coverage of fundamentals of computer graphics.
3D Transformations
Reflections
3D Display methods
3D Object Representation
Polygon surfaces
Quadratic Surfaces
A graphics monitor is a display that can show graphics in addition to text. Graphics monitors are used in applications like air traffic control, medical imaging, and CAD. A workstation is a powerful computer optimized for visualization and manipulation of complex data like 3D modeling, simulation, and image rendering. Workstations have specifications like 64MB or more of RAM, high-resolution graphics screens, large displays, and built-in network support. They are used for graphics-intensive applications like 3D design, video editing, and CAD. A server handles data requests from other computers on a network and hosts applications, while a workstation is a personal computer used for graphics applications and intensive programs by professional users.
This document provides an overview of computer graphics systems. It discusses the basic components of a graphics system including input, computation, and output. For output, it describes raster display technologies like cathode ray tubes (CRTs) and liquid crystal displays (LCDs). It also discusses graphics memory and framebuffers for storing pixel color values, as well as color depth and dithering techniques. The goal of computer graphics is to solve the color function for each pixel on the display.
The document discusses several networking concepts:
- Classless Inter-Domain Routing (CIDR) allows ISPs to allocate blocks of IP addresses to organizations in a more efficient manner than previous methods.
- Network Address Translation (NAT) allows a local network to use private IP address ranges behind a NAT-enabled router that maps the private addresses to a single public IP address for communication with external networks.
- Subnetting and Variable Length Subnet Masking (VLSM) allow networks to be divided into subnets to better utilize limited IP address blocks and assign addresses based on subnet needs.
- Supernetting combines multiple classful network blocks into larger supernets to more efficiently use address space.
This document discusses line attributes in computer graphics, including line type (solid, dashed, dotted), width, caps (butt, round, projecting square), joins (miter, round, bevel), and color. It describes how to set these attributes using functions like setLinetype(), setLinewidthscaleFactor(), and setPolylineColourIndex(). Lines can also be displayed using pen or brush options which have properties like shape, size, and patterns.
Raster scan displays work by sweeping an electron beam across the screen one row at a time, turning the beam on and off to illuminate spots and form an image. The intensity values for each screen point are stored in a refresh buffer and then retrieved to paint the image on the screen. Refresh rates are typically 60-80 frames per second. Random scan displays draw images using geometric primitives and store picture definitions as drawing commands in a refresh display file. Color CRT monitors use either beam penetration or a shadow mask method to display color images by emitting light from red, green, and blue phosphor dots.
This document discusses various 3D transformations including translation, rotation, scaling, reflection, and shearing. It provides the transformation matrices for each type of 3D transformation. It also discusses combining multiple transformations through composite transformations by multiplying the matrices in sequence from right to left.
This document discusses 2D geometric transformations including translation, rotation, and scaling. It provides the mathematical definitions and matrix representations for each transformation. Translation moves an object along a straight path, rotation moves it along a circular path, and scaling changes its size. All transformations can be represented by 3x3 matrices using homogeneous coordinates to allow combinations of multiple transformations. The inverse of each transformation matrix is also defined.
The A-buffer method is an extension of the depth-buffer method that allows for anti-aliasing and transparency. It works by building a pixel mask for each polygon fragment and determining the visible areas to average color values. The key data structure is the accumulation buffer, which stores color, opacity, depth, coverage, and other data for each pixel. It operates similar to a depth buffer but also considers opacity to determine the final pixel color.
This document provides an overview of computer graphics and its applications. It discusses various types of video display devices used in computer graphics like CRTs and flat panel displays. It describes how raster scan and random scan systems work and lists common input and output devices. The document outlines different chapters that will cover topics like line and curve generation algorithms, transformations, 3D viewing, surface detection, and modeling techniques. It provides examples of how computer graphics is used in fields like CAD, presentations, entertainment, education, visualization, image processing, and graphical user interfaces.
The document describes various types of computer display devices and their characteristics. It discusses raster and random scan displays, CRT monitors, color CRT technologies including beam penetration and shadow mask methods, and other display types such as direct view storage tubes. Input devices are also covered, including keyboards, mice, digitizers, and touch screens.
The document discusses the 2D viewing pipeline. It describes how a 3D world coordinate scene is constructed and then transformed through a series of steps to 2D device coordinates that can be displayed. These steps include converting to viewing coordinates using a window-to-viewport transformation, then mapping to normalized and finally device coordinates. It also covers techniques for clipping objects and lines that fall outside the viewing window including Cohen-Sutherland line clipping and Sutherland-Hodgeman polygon clipping.
This document discusses various attributes that can be used to modify the appearance of graphical primitives like lines and curves when displaying them, including line type (solid, dashed, dotted), width, color, fill style (hollow, solid, patterned), and fill color/pattern. It describes how these attributes are specified in applications and how different rendering techniques like rasterization can be used to display primitives with various attribute settings.
it is a Visible surface detection method is also known as depth buffer method. In this method detect the visible surface by using the distance of the object from the projections plane.
The depth buffer method is used to determine visibility in 3D graphics by testing the depth (z-coordinate) of each surface to determine the closest visible surface. It involves using two buffers - a depth buffer to store the depth values and a frame buffer to store color values. For each pixel, the depth value is calculated and compared to the existing value in the depth buffer, and if closer the color and depth values are updated in the respective buffers. This method is implemented efficiently in hardware and processes surfaces one at a time in any order.
The document discusses line drawing algorithms in computer graphics. It defines a line segment and provides equations to determine the slope and y-intercept of a line given two endpoints. It then introduces the Digital Differential Analyzer (DDA) algorithm, an incremental scan conversion method that calculates the next point on the line based on the previous point's coordinates and the line's slope. The algorithm involves less floating point computation than directly using the line equation at each step. An example demonstrates applying DDA to scan convert a line between two points. Limitations of DDA include the processing costs of rounding and floating point arithmetic as well as accumulated round-off error over long line segments.
Polygon clipping involves taking a polygon and clipping it against another shape to produce one or more smaller polygons. The Sutherland-Hodgman algorithm handles polygon clipping by testing each edge of the clipping polygon against each edge of the clip shape. There are four cases for how an edge can be clipped - wholly inside, exit, wholly outside, enter - and the algorithm saves or discards vertices based on these cases. Repeatedly clipping against each edge of the clip shape handles all cases and produces the final clipped polygon(s).
2D transformations are important operations in computer graphics that allow modifying the position, size, and orientation of objects in a 2D plane. There are several types of 2D transformations including translation, rotation, scaling, and more. Transformations are represented using matrix math for efficient application of sequential transformations. Key techniques include homogeneous coordinates to allow different types of transformations to be combined into a single matrix operation.
with today's advanced technology like photoshop, paint etc. we need to understand some basic concepts like how they are cropping the image , tilt the image etc.
In our presentation you will find basic introduction of 2D transformation.
The document discusses window to viewport transformation. It defines a window as a world coordinate area selected for display and a viewport as a rectangular region of the screen selected for displaying objects. Window to viewport mapping requires transforming coordinates from the window to the viewport. This involves translation, scaling and another translation. Steps include translating the window to the origin, resizing it based on the viewport size, and translating it to the viewport position. An example transforms a sample window to a viewport through these three steps.
Comprehensive coverage of fundamentals of computer graphics.
3D Transformations
Reflections
3D Display methods
3D Object Representation
Polygon surfaces
Quadratic Surfaces
A graphics monitor is a display that can show graphics in addition to text. Graphics monitors are used in applications like air traffic control, medical imaging, and CAD. A workstation is a powerful computer optimized for visualization and manipulation of complex data like 3D modeling, simulation, and image rendering. Workstations have specifications like 64MB or more of RAM, high-resolution graphics screens, large displays, and built-in network support. They are used for graphics-intensive applications like 3D design, video editing, and CAD. A server handles data requests from other computers on a network and hosts applications, while a workstation is a personal computer used for graphics applications and intensive programs by professional users.
This document provides an overview of computer graphics systems. It discusses the basic components of a graphics system including input, computation, and output. For output, it describes raster display technologies like cathode ray tubes (CRTs) and liquid crystal displays (LCDs). It also discusses graphics memory and framebuffers for storing pixel color values, as well as color depth and dithering techniques. The goal of computer graphics is to solve the color function for each pixel on the display.
The document discusses several networking concepts:
- Classless Inter-Domain Routing (CIDR) allows ISPs to allocate blocks of IP addresses to organizations in a more efficient manner than previous methods.
- Network Address Translation (NAT) allows a local network to use private IP address ranges behind a NAT-enabled router that maps the private addresses to a single public IP address for communication with external networks.
- Subnetting and Variable Length Subnet Masking (VLSM) allow networks to be divided into subnets to better utilize limited IP address blocks and assign addresses based on subnet needs.
- Supernetting combines multiple classful network blocks into larger supernets to more efficiently use address space.
This document provides an overview of computer graphics. It discusses the definition of computer graphics, goals of computer graphics, applications of computer graphics, graphics systems including images, hardware and software. It also describes two dimensional and three dimensional images, color models, input devices like keyboards and scanners, the computation stage involving transformations and rasterization, output devices like displays, and basics of animation.
The document discusses computer communication architecture and the OSI and TCP/IP models. It provides details on each layer of the OSI model, including the layer number, name, function, and PDU. It also discusses data encapsulation, analogies to explain how data moves through the OSI layers, and compares the OSI and TCP/IP models. The TCP/IP model has fewer layers and is focused on interoperability rather than standards.
This document provides an overview of digital communication and covers several topics:
- It describes different types of transmission media including guided media like twisted pair cable, coaxial cable, and fiber optic cable. It also covers unguided or wireless media.
- It discusses characteristics of different transmission media and how signals are transmitted through them. This includes concepts like attenuation, distortion, and noise.
- It defines key terms used to measure signal quality like decibels and signal-to-noise ratio.
The document provides an overview of wireless networks and wireless communication technologies. It discusses the key elements of a wireless network including wireless hosts, base stations, wireless links, infrastructure and ad hoc modes. It also covers wireless link characteristics such as signal attenuation, interference and multipath propagation. Finally, it introduces common wireless network standards and protocols including IEEE 802.11 wireless LANs, wireless network characteristics such as the hidden terminal problem, and wireless multiple access protocols.
The data link layer provides services to the network layer such as framing data and applying error detection methods like parity checks, checksums and cyclic redundancy checks to frames. Common data link protocols are used at this layer.
This document provides an overview of computer graphics hardware and software. It defines computer graphics as using a computer to define, store, manipulate, interrogate and present pictorial output. The key hardware components discussed are display devices like CRT, LCD, and plasma displays. Software components include rendering primitives, algorithms for transformation and rasterization, and application programming interfaces that provide access to graphics hardware. The graphics rendering pipeline is described as the process of converting a 3D scene model into a 2D image through steps like modeling transformations, viewing transformations, projection, clipping and rasterization.
The document discusses raster graphics and how images are displayed. It covers several topics:
1) Display hardware such as CRT, LCD, and other devices used to output images.
2) Raster graphics systems and how imaging systems are organized with a frame buffer and refresh rate.
3) Output primitives like points, lines, polygons that are used to describe shapes. It discusses algorithms for drawing lines like DDA and Bresenham.
4) Color models for representing and describing colors in raster graphics.
The Cathode Ray Tube (CRT) is a type of monitor that was first discovered in the late 19th century and remained popular for over 70 years. It works by using an electron gun to emit light onto phosphors on the inside of a glass screen, creating vivid colors and detailed images. While CRTs are bulky, power-hungry, and can emit small amounts of radiation, they were less expensive than newer LCD displays and provided good image quality from any viewing angle until being replaced by flat panel displays.
Raster scan systems use a video controller to control the display device and refresh the screen. The video controller is given direct access to a frame buffer in system memory. It refreshes the screen by incrementing through pixel coordinates stored in the frame buffer and using the stored intensity values to set the intensity of each pixel on the CRT monitor. More advanced systems use separate display processors and multiple frame buffers to speed up processing and enable real-time animation.
The document describes routing algorithms used in computer networks. It discusses two main types of routing algorithms: link-state algorithms and distance-vector algorithms. Link-state algorithms use a complete map of the entire network topology to calculate the shortest paths between all nodes, while distance-vector algorithms use an iterative process where each router shares routing information with neighbors to determine the shortest paths. The document then provides examples of how Dijkstra's algorithm, a link-state algorithm, and the Bellman-Ford distance-vector algorithm work to calculate the optimal paths through a sample network.
Raster scanning is a process used in television and computer graphics where an image is captured and reconstructed by systematically scanning across it in horizontal lines from top to bottom. Each line, called a scan line, is transmitted as an analog signal or divided into discrete pixels. Pixels are stored in a refresh buffer and then "painted" onto the screen one row at a time, with the beam returning to the left side during horizontal retrace and to the top left for vertical retrace between frames. Raster scanning provides realistic images but at the cost of lower resolution compared to random scanning systems.
The document discusses different types of video display devices including cathode ray tube (CRT) displays and flat panel displays. CRT displays use an electron gun to create images on a phosphorus screen but have disadvantages like large size, weight, and high power consumption. Flat panel displays like liquid crystal displays (LCDs) and plasma display panels are thinner, lighter, and use less power than CRTs. LCDs have advantages such as portability, reduced eyestrain, and thin panels but have limitations like dependence on viewing angle and slower response times. Plasma displays can be large, have good color rendering, and brightness but also have high costs and power consumption.
Raster animation is created by displaying a sequence of raster images rapidly to create the illusion of motion. Each raster image is stored as a bitmap in system memory and contains information about individual pixels that make up the image. By refreshing the frame buffer with a new bitmap, raster animation is created. There are two main types - traditional using sprite sheets and modern using programming languages. Raster animation provides more realistic images than vector animation but requires more memory and processing power. It is used for applications like 3D/2D animation, games, and movies.
Cathode ray tube (CRT) displays were commonly used but are being replaced by newer technologies. CRTs use electron guns and phosphors to display images but have disadvantages like large size, weight, and power consumption. LCD displays use liquid crystals and do not emit light, instead blocking light to produce images. They are thinner and more energy efficient than CRTs but have limited viewing angles. Plasma displays utilize cells of charged gases to produce bright, large displays but also consume more power than LCDs. Newer technologies continue to improve on displays, with OLED providing thinner, more efficient self-emissive panels, LED backlights enhancing LCDs, and higher resolution 4K becoming more common.
Direct-view storage tubes store picture information directly behind the screen using an electron beam to write a charged pattern on a fine mesh grid coated with dielectric. A flood electron gun then emits a continuous flood of electrons that pass through the grid, attaching to positively charged portions and striking the phosphors. This stored charge pattern is what displays the image without needing refreshment like a standard CRT. Advantages are very high resolution images without flicker, while disadvantages are inability to display color and inability to fully erase selected areas.
Monitors use either cathode ray tubes or LCD screens to display computer output visually. CRTs were dominant until the 21st century when they were replaced by thinner and lighter LCD screens. Random-scan displays draw images line by line like vectors and refresh each line 30-60 times per second to prevent screen burn-in, while flat panel displays are now commonly used in portable devices due to their thinness.
The document discusses the history and development of chocolate over centuries. It details how cocoa beans were first used as currency by the Maya and Aztecs before being introduced to Europe in the 16th century. The document then explains how chocolate became popularized as a drink in Europe in the 17th century and how its production and consumption expanded globally over subsequent centuries.
This PPT gives detailed information about Computer Graphics, Raster Scan System, Random Scan System, CRT Display, Color CRT Monitors, Input and Output Devices
This document provides an overview of video display devices and color graphics technologies. It discusses raster scan displays, which refresh the screen by sweeping the electron beam across rows of pixels stored in a frame buffer. Random scan displays direct the electron beam only where needed to draw lines, allowing higher resolution but not realistic images. Color CRT monitors use shadow mask or beam penetration methods, with the former allowing a wider range of colors by exciting red, green, and blue phosphor dots. Flat panel displays are thinner than CRTs and being used in more portable applications.
The document summarizes video display devices, specifically cathode ray tubes (CRTs). It describes the basic design of CRTs including the electron gun, phosphor coating, and refresh process. CRTs use an electron beam directed by deflection systems to illuminate spots on the screen in a raster pattern, maintained by refreshing the screen rapidly. Color CRTs employ different color phosphors and methods like beam penetration or shadow masks to combine colors. Random scan displays draw images as lines rather than pixels.
This document provides information about different types of display devices used in computer graphics. It discusses cathode ray tubes (CRTs) which produce images using an electron beam striking a phosphorescent screen. CRTs are bulky and electromagnetic fields may pose health risks. Raster scan displays redraw images by sweeping an electron beam across the screen in lines. Color CRTs use phosphors and shadow masks to produce colors. Flat panel displays like liquid crystal displays are thinner alternatives to CRTs.
The document summarizes key differences between vector scan and raster scan displays. Vector scan displays directly draw lines between points by moving the electron beam between endpoints, while raster scan displays sweep the beam across the entire screen in lines from top to bottom. Raster scan is more common as it does not flicker even with complex images and has lower cost and hardware requirements than vector scan. Both methods store images in a frame buffer but raster scan must convert graphics to pixels while vector scan does not.
CG03 Random Raster Scan displays and Color CRTs.ppsxjyoti_lakhani
The document discusses different types of graphics displays. It describes raster-scan displays, which use an electron beam that sweeps across the screen from top to bottom to display an image. Picture definition is stored in a frame buffer. It also describes random-scan displays, which direct the electron beam only where lines need to be drawn. Color CRT monitors use phosphors and a shadow mask to display color. Flat panel displays like plasma panels, thin-film electroluminescent displays, and liquid crystal displays provide thinner alternatives to CRTs.
The document provides an overview of computer graphics systems. It discusses different types of display devices including refresh cathode-ray tubes, raster-scan displays, random-scan displays, color CRT monitors, and flat panel displays. It also covers basics of raster graphics systems and random scan systems, including components like the video controller, display processor, and frame buffer. Input devices for graphics systems such as the keyboard, mouse, and digitizer are also mentioned.
The document discusses various types of raster images and display technologies. Raster images represent pictures as a grid of pixels stored as numerical values. Grayscale images vary pixel depth to generate different colors. Color images use three values per pixel. Display technologies discussed include CRTs, LCDs, plasma displays, and other emissive and non-emissive displays. CRTs use electron guns and phosphors to generate images while LCDs use liquid crystals and polarized light.
This document provides an overview of graphics display systems. It discusses the basic components and operation of cathode ray tube (CRT) displays, including the electron gun, focusing and deflection systems. It describes the refresh process of raster-scan CRTs and how random-scan CRTs work. Color CRT monitors are discussed, specifically the beam penetration and shadow mask methods. Key characteristics like resolution, persistence and aspect ratio are also summarized.
This document summarizes different types of display devices, including cathode ray tubes (CRTs), raster scan displays, random scan displays, liquid crystal displays (LCDs), and light emitting diodes (LEDs). It describes the basic components and functioning of CRTs, including electron guns, phosphor coatings, and deflection coils. It compares raster and random scan displays, noting that raster displays are better for realistic images while random scans are suited for line drawings. LCDs use polarized light passing through liquid crystals to turn pixels on and off. LED displays use semiconductors to emit light when forward biased, and have advantages over traditional light sources like lower energy use and longer lifetimes.
The document discusses various display devices used for visual presentation of information. It describes cathode ray tubes (CRT), which use electron guns and phosphorescent coatings to produce images. Raster scan displays refresh images by sweeping an electron beam across the screen in rows, while random scan displays draw individual lines. Liquid crystal displays (LCD) use polarized light passing through liquid crystals. Light emitting diodes (LED) also emit light when electrically biased and are used in displays and lighting due to their low energy use and long lifetime. The document provides details on the components and functioning of CRTs and explains the differences between raster and random scan displays.
This document summarizes computer graphics and display devices. It discusses that computer graphics involves displaying and manipulating images and data using a computer. A typical graphics system includes a host computer, display devices like monitors, and input devices like keyboards and mice. Common applications of computer graphics include GUIs, charts, CAD/CAM, maps, multimedia, and more. Display technologies discussed include CRT monitors, LCD panels, and other devices. Key aspects of CRT monitors like refresh rate, resolution, and bandwidth are also summarized.
This document discusses computer graphics systems and their components. It describes common display devices like CRT monitors and how they work. It explains color generation techniques in monitors using beam penetration or shadow mask methods. Input devices for graphics like mice, tablets, and joysticks are also covered. The document provides details on frame buffers, resolution, refresh rates and how raster scan displays redraw images.
Introduction to computer graphics part 1Ankit Garg
This document discusses computer graphics systems and their components. It describes video display devices like CRTs and how they work. Color is generated using techniques like beam penetration and shadow masks. Raster scan and random scan displays are covered. Input devices for graphics like mice, tablets, and gloves are also summarized. The document provides details on graphics hardware like frame buffers, refresh rates, and video controllers.
This document discusses computer graphics and its applications. It defines computer graphics as the field concerned with digitally synthesizing and manipulating visual content. The two main types are raster (composed of pixels) and vector (composed of paths). Raster images are bitmaps mapped to a grid, while vector images use mathematical formulas. Common graphics applications include paint programs, animation software, CAD, and desktop publishing. Cathode ray tubes are used to display images by scanning an electron beam across a screen coated with phosphors.
This document discusses computer graphics and its various aspects. It defines computer graphics as the field concerned with digitally synthesizing and manipulating visual content. The two main types of computer graphics are raster (composed of pixels) and vector (composed of paths). Raster images are bitmap images mapped to a grid of pixels that can be edited at the pixel level. Vector images use mathematical formulas to draw objects like lines and curves. Common graphics applications include paint programs, animation software, CAD, and desktop publishing. Cathode ray tubes are used to display images by scanning an electron beam across a screen coated with phosphors.
Computer graphics refers to creating, manipulating, and displaying visual images and animations using computers. There are two main types: interactive and non-interactive. Computer graphics has many applications including graphical user interfaces, plotting graphs and charts, simulations, entertainment, CAD/CAM, medicine, history, art, and cartography. Raster and vector graphics are the two main types of computer graphics representations. Raster uses a grid of pixels while vector uses mathematical formulas to define shapes.
Raster scan displays work by sweeping an electron beam across the screen in horizontal lines from top to bottom. As the beam moves, its intensity is turned on and off to illuminate pixels and form an image. The pixel values are stored in and retrieved from a refresh buffer or frame buffer. Random scan displays draw images using geometric primitives like points and lines based on mathematical equations, directing the electron beam only where needed. Raster scans have higher resolution but jagged lines, while random scans produce smooth lines but cannot display complex images. Both use a video controller and frame buffer in memory to control the display process.
Computer Graphics is an advance field in information technology and all about manipulation and rendering of images. This presentation covers all the main concepts in computer graphics including graphics algorithms.
This document discusses various computer arithmetic operations including addition, subtraction, multiplication, and division for signed magnitude and two's complement data representations. It describes the Booth multiplication algorithm, array multipliers for performing multiplication using combinational circuits, and the division algorithm. It also covers detecting divide overflow conditions.
The document provides an introduction to computer security including:
- The basic components of security such as confidentiality, integrity, and availability.
- Common security threats like snooping, modification, and denial of service attacks.
- Issues with security including operational challenges and human factors.
- An overview of security policies, access control models, and security models like Bell-LaPadula and Biba.
Cookies and sessions allow servers to remember information about users across multiple web pages. Cookies are small files stored on a user's computer that identify users and can store data to be accessed on subsequent page requests. Sessions use cookies to identify users and store temporary data on the server side to be accessed across multiple pages in one application, such as usernames or preferences. Both cookies and sessions must be started before any page output to ensure headers are sent before the page body.
This document discusses different aspects of functions in programming including declaring and calling functions, passing arguments to functions, and returning values from functions. It also covers variable scope. Some key points covered are declaring functions with and without arguments, specifying default values, returning single values or arrays from functions, and understanding variable scope and how it relates to the global and $GLOBALS keywords and array.
This document discusses various aspects of working with web forms in PHP, including:
1) Useful server variables for forms like QUERY_STRING and SERVER_NAME.
2) Accessing form parameters submitted to the server.
3) Processing forms with functions, including validating form data with techniques like checking for required fields and valid email addresses.
4) Displaying default values or error messages for form fields.
5) Stripping HTML tags from form inputs and encoding special characters for safe display.
The document provides examples of implementing each of these techniques.
The document discusses various programming concepts related to decision making and repetition in code including understanding true and false values, using if/elseif/else statements, equality and relational operators, logical operators, and using while and for loops to repeat code. Specific topics covered include evaluating booleans, making single and multi-line if statements, comparing different data types, negation, and printing select menus with loops.
This document discusses working with arrays in PHP. It covers array basics like creating and accessing arrays, looping through arrays with foreach and for loops, modifying arrays by adding/removing elements and sorting arrays. It also discusses multidimensional arrays, how to create them and access elements within them.
This document discusses text and numbers in programming. It covers defining and manipulating text strings using single or double quotes. Escape characters can be used inside strings. Text can be validated and formatted using various string functions like trim(), strlen(), strtoupper(), substr(), and str_replace(). Numbers can be integers or floats. Variables hold data and can be operated on with arithmetic and assignment operators like +, -, *, /, %, and .=. Variables can also be incremented, decremented, and placed inside strings.
This document provides an introduction and overview of PHP for beginners. It discusses PHP's use for building websites, how PHP code is run on web servers and accessed through browsers. It then highlights some key advantages of PHP like being free, cross-platform, and widely used. It demonstrates a basic "Hello World" PHP program and shows how to output HTML forms and formatted numbers. Finally, it outlines some basic rules of PHP programs regarding tags, syntax, whitespace, comments, and case sensitivity.
The document discusses capacity planning for a data warehouse environment. It notes that capacity planning is important given the large volumes of data and processing in a data warehouse. It describes factors that make capacity planning unique for a data warehouse, such as variable workloads and larger data volumes than operational systems. The document provides guidance on estimating disk storage needs, classifying and estimating processing workloads, creating workload profiles, identifying peak capacity needs, and selecting hardware capacity to meet needs.
Data warehousing involves assembling and managing data from various sources to provide an integrated view of enterprise information. A data warehouse contains consolidated, historical data used to support management decision making. It differs from operational databases by containing aggregated, non-volatile data optimized for queries rather than updates. The extract, transform, load (ETL) process migrates data from source systems to the warehouse, transforming it as needed. Process managers oversee loading, maintaining, and querying the warehouse data.
Search engines allow users to search the vast collection of documents on the web. They consist of crawlers that fetch web pages, indexers that analyze page content and links, and interfaces that allow users to enter queries. Crawlers add pages to an index by following links, and indexers create inverted indexes to map words to pages. When a query is searched, results are retrieved from the index and ranked based on relevance. PageRank is a key algorithm that ranks pages higher that receive more links from other highly ranked pages. While it effectively searches the large, diverse and dynamic web, search poses challenges in understanding ambiguous queries over an evolving collection.
Web mining involves applying data mining techniques to discover useful information from web data. There are three types of web mining: web content mining analyzes data within web pages, web structure mining examines the hyperlink structure between pages, and web usage mining involves analyzing server logs to discover patterns in user behavior and interactions with websites. Web mining has applications in website design, web traffic analysis, e-commerce personalization, and security/crime investigation.
Information privacy and data mining
The document discusses information privacy and data mining. It defines information privacy as an individual's ability to control how information about them is shared. It outlines the basic OECD principles for protecting information privacy, including collection limitation, purpose specification, use limitation, security safeguards, and accountability. It describes common uses of data mining like fraud prevention but also potential misuses that can violate privacy. The document also discusses the primary aims of data mining applications and five pitfalls like unintentional mistakes, intentional abuse, and mission creep.
The document discusses cluster analysis, which groups data objects into clusters so that objects within a cluster are similar but dissimilar to objects in other clusters. It describes key characteristics of clustering, including that it is unsupervised learning and the clusters are determined algorithmically rather than by humans. Various clustering algorithms are covered, including partitioning, hierarchical, density-based, and grid-based methods. Applications of clustering discussed include business intelligence, image recognition, web search, outlier detection, and biology. Requirements for effective clustering in data mining are also outlined.
Association analysis is a technique used to uncover relationships between items in transactional data. It involves finding frequent itemsets whose occurrence exceeds a minimum support threshold, and then generating association rules from these itemsets that satisfy minimum confidence. The Apriori algorithm is commonly used for this task, as it leverages the Apriori property to prune the search space - if an itemset is infrequent, its supersets cannot be frequent. It performs multiple database scans to iteratively grow frequent itemsets and extract high confidence rules.
Classification techniques in data miningKamal Acharya
The document discusses classification algorithms in machine learning. It provides an overview of various classification algorithms including decision tree classifiers, rule-based classifiers, nearest neighbor classifiers, Bayesian classifiers, and artificial neural network classifiers. It then describes the supervised learning process for classification, which involves using a training set to construct a classification model and then applying the model to a test set to classify new data. Finally, it provides a detailed example of how a decision tree classifier is constructed from a training dataset and how it can be used to classify data in the test set.
This document outlines a chapter on data preprocessing that discusses data types, attributes, and preprocessing tasks. It begins by defining data and attributes, then describes different types of attributes like nominal, binary, ordinal, and numeric attributes. It also discusses different types of datasets like records, documents, transactions, and graphs. The major section on data preprocessing outlines why it is important and describes tasks like data cleaning, integration, transformation, reduction, and discretization to prepare dirty or unstructured data for analysis.
Introduction to Data Mining and Data WarehousingKamal Acharya
This document provides details about a course on data mining and data warehousing. The course objectives are to understand the foundational principles and techniques of data mining and data warehousing. The course description covers topics like data preprocessing, classification, association analysis, cluster analysis, and data warehouses. The course is divided into 10 units that cover concepts and algorithms for data mining techniques. Practical exercises are included to apply techniques to real-world data problems.
How to Create a Stage or a Pipeline in Odoo 17 CRMCeline George
Using CRM module, we can manage and keep track of all new leads and opportunities in one location. It helps to manage your sales pipeline with customizable stages. In this slide let’s discuss how to create a stage or pipeline inside the CRM module in odoo 17.
Andreas Schleicher presents PISA 2022 Volume III - Creative Thinking - 18 Jun...EduSkills OECD
Andreas Schleicher, Director of Education and Skills at the OECD presents at the launch of PISA 2022 Volume III - Creative Minds, Creative Schools on 18 June 2024.
Creative Restart 2024: Mike Martin - Finding a way around “no”Taste
Ideas that are good for business and good for the world that we live in, are what I’m passionate about.
Some ideas take a year to make, some take 8 years. I want to share two projects that best illustrate this and why it is never good to stop at “no”.
Information and Communication Technology in EducationMJDuyan
(𝐓𝐋𝐄 𝟏𝟎𝟎) (𝐋𝐞𝐬𝐬𝐨𝐧 2)-𝐏𝐫𝐞𝐥𝐢𝐦𝐬
𝐄𝐱𝐩𝐥𝐚𝐢𝐧 𝐭𝐡𝐞 𝐈𝐂𝐓 𝐢𝐧 𝐞𝐝𝐮𝐜𝐚𝐭𝐢𝐨𝐧:
Students will be able to explain the role and impact of Information and Communication Technology (ICT) in education. They will understand how ICT tools, such as computers, the internet, and educational software, enhance learning and teaching processes. By exploring various ICT applications, students will recognize how these technologies facilitate access to information, improve communication, support collaboration, and enable personalized learning experiences.
𝐃𝐢𝐬𝐜𝐮𝐬𝐬 𝐭𝐡𝐞 𝐫𝐞𝐥𝐢𝐚𝐛𝐥𝐞 𝐬𝐨𝐮𝐫𝐜𝐞𝐬 𝐨𝐧 𝐭𝐡𝐞 𝐢𝐧𝐭𝐞𝐫𝐧𝐞𝐭:
-Students will be able to discuss what constitutes reliable sources on the internet. They will learn to identify key characteristics of trustworthy information, such as credibility, accuracy, and authority. By examining different types of online sources, students will develop skills to evaluate the reliability of websites and content, ensuring they can distinguish between reputable information and misinformation.
A Free 200-Page eBook ~ Brain and Mind Exercise.pptxOH TEIK BIN
(A Free eBook comprising 3 Sets of Presentation of a selection of Puzzles, Brain Teasers and Thinking Problems to exercise both the mind and the Right and Left Brain. To help keep the mind and brain fit and healthy. Good for both the young and old alike.
Answers are given for all the puzzles and problems.)
With Metta,
Bro. Oh Teik Bin 🙏🤓🤔🥰
2. Video Display Devices
The primary output device in a graphics system is a
video monitor.
The operation of most video monitor is based on the
standard Cathode Ray Tube(CRT)
3. Refresh Cathode Ray Tubes
Electron are “boiled off” the surface of cathode by
heating it with the help of the heating filament.
The accelerating voltage is generated with the help of
positively charged metal coating on the inside of CRT
envelope or an accelerating anode can be used.
The intensity of the electron beam is controlled by
setting the negative voltage of the control grid.
Focusing system is needed to force the electron beam
to converge into small spot as it strikes the
phosphorous.
4. Focusing can be implemented with the help of
electric field or the magnetic field.
As in the case of focusing of the electron, the
deflection of the electron can be controlled by using
either magnetic or the electric field.
5.
6.
7.
8. Different kind of Phosphors are available for use in
CRT. Beside color major difference between
phosphors is their persistence.
Persistence is defined as the time it takes for the
emitted light on the screen to decay one-tenth of its
original intensity.
A phosphors with low persistence is used in
animation while the other one is useful in displaying
highly complex, static pictures.
9. The maximum number of points that can be
displayed on the screen without overlap is referred to
as the resolution.
High resolution system are referred to as high-
definition system.
The physical size of the graphical monitor is given as
the length of the screen diagonal.
Aspect ratio is the ratio of vertical points to
horizontal points required to produce equal length
lines in both direction on the screen.
10. Raster Scan Display
The electron beam is swept across the screen one
row at a time top to bottom.
As the electron beam moves across each row, beam
intensity is turned ON and OFF to create the pattern
of illuminated spots.
Picture definition is stored in the memory area called
refresh buffer or frame buffer.
Each screen point is referred to as pixel or
pel(picture element)
11. On a black white system with one bit per pixel, the
frame buffer is commonly called bitmap.
For a system with multiple bits per pixel, the frame
buffer is often referred to as pixmap.
Refreshing on raster scan display is carried out at the
rate of 60 to 80 frames per second.
On some rater scan system, each frame is displayed
in two passes using an interlaced refresh procedure.
12.
13.
14. Interlaced vs Non-Interlaced Scan
In interlaced scan, each frame is displayed in two
passes. First pass for odd scan lines and second for
the even.
In non-interlaced scan, electron beam sweep over all
the scan lines.
15. Question
Consider a RGB raster system is to be designed using 8
inch by 10 inch screen with a resolution of 100 pixels
per inch in each direction. If we want to store 8 bits per
pixel in the frame buffer, how much storage (in bytes)
do we need for the frame buffer?
16. Question
Consider 512 pixels X 512 scan lines image with 24-bit
true color. If 5 minutes video is required to capture,
calculate the total memory required?
17. Random scan display
Electron beam is directed only to part of the screen
where a picture is to be drawn.
It is also referred to as vector display or stroke-
writing or calligraphic displays.
The components lines of a picture can be drawn and
refreshed in any specified order.
Refresh rate depends on the number of lines to be
displayed.
Picture set is stored as the line drawing commands in
memory called refresh display file or display list or
display program or simply refresh buffer.
18. It is suited for line drawing application and cannot
display realistic shaded scenes.
Vector display has higher resolution than raster scan
display.
Vector display produce smooth line drawing as beam
directly follow the line path.
19.
20. Color CRT Monitors
Color pictures can be displayed by using a
combination of phosphors that emit different colored
light.
By combining these different light, range of colors
can be generated.
Two basic techniques used are:
Beam Penetration
Shadow Mask
21. Beam Penetration
This method is used with random scan monitors.
Two layers of phosphors, usually red and green are
coated inside CRT.
The colors are displayed depending on how far the
electron beam penetrates the phosphors layers.
Beam of slow electrons excite only outer red layer,
fast beam can penetrated deep to excite both layer.
Only four colors are possible and quality of pictures
is not as good as with other methods.
22. Shadow Mask
It is used on raster scan system(including color TV).
It produces much wider range of colors than beam
penetration method.
It has three phosphor color dots(red, green, blue) at
each pixel position.
It has three electron gun one for each color dot and
shadow mask grid just behind the phosphors coated
screen.
The three electron beams are deflected and focused
as group onto shadow mask, which contain series of
holes aligned with phosphors dot pattern.
23. There are two primary variations
Stripe Pattern
Delta Pattern
24.
25. Delta-delta CRT
When three beam pass through the hole in the
shadow mask, they activate the dot triangle, which
appear as a small color dot on screen.
Various colors can be generated by varying the
intensity of the three electron guns.
Difficulties are faced while aligning the shadow mask
hole and respective triads.
28. Direct View Storage Tubes(DVST)
It store the picture information as a charge
distribution just behind the phosphors coated
screen.
Two electrons gun are used. Primary gun to store
picture pattern and the second flood gun, maintains
the picture display.
Because no refreshing is needed, very complex
pictures can be displayed at very high resolution
without any flicker.
29. Disadvantage is that they ordinarily do not display
color and selected part of the pictures can not be
displayed.
To eliminate the picture section, the entire screen
must be erased and modified picture is redrawn.
30. Flat Panel display
Flat panel display refers to class of video devices that
have reduced volume, weight and power
requirements compared to CRT.
They are used in calculators, pocket video games,
laptops, Tv monitors etc.
We can separate flat panel displays into two
categories:
Emissive displays
Non-emissive displays
31. Emissive display are the devices that convert the
electrical energy into light. Examples are plasma
panel, LED etc.
Non-emissive display use optical effects to convert
sunlight or light from some other source into
graphical patterns. Example LCD
35. Raster Scan display processor
Display processor is also called graphics controller or
display coprocessor.
Its purpose is to free the CPU from the graphics part.
In addition to the system memory separate display
processor memory can also be provided.
The major task is to digitize the picture definition
into set of pixel-intensity values for storage in the
frame buffer.
The digitization process is called scan conversion.
37. Random Scan System
An application program is input and store in the
system memory along with graphics package.
Graphics command in application program are
translated by graphics package and stored in the
display file in the system memory.
This display file is accessed by the processor to
refresh screen.
Graphics pattern are drawn by directing electron
beam along components line of the picture.
40. Hard-copy devices
We can obtain hard copy output of the images using
various hard copy devices.
The quality of the pictures obtain from the device
depends on the dot size and the number of dots per
inch.
These can be of two types:
Impact
Non-Impact
41. Impact printer pressed the formed character against
the ribbon on to the paper.
Non-impact system uses the laser technology.
Examples laser printer, plotters etc.
42. Graphics Software
Two general classification of graphics software:
General Programming Package
Special Purpose application package.
General programming package provides an extensive
set of graphics function that can be used in high level
programming such C or Fortran. Example
GL(Graphics library)
Special purpose application package is designed for
the non-programmer. Example CAD system
雅虎竞拍
煤炉代买
paypay商城
乐天二手
日本亚马逊
乐天新品
ZOZOTOWN
