The document provides an overview of computer graphics, covering its definition, importance across various industries, and historical developments. It details various types of graphics, essential components, and applications in fields such as virtual reality, gaming, and digital design. Additionally, it discusses digital imaging concepts, color models, image formats, and photo editing techniques, including popular software like Adobe Photoshop.

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1. Introduction to Computer Graphics
1.1 What is Computer Graphics?
• Definition:
• Computer graphics is the art and science of creating, manipulating,
and displaying visual content using computers. It encompasses
everything from simple 2D drawings to complex 3D animations and
simulations.
• Key Concepts:
• Visualization of data, rendering, modeling, image processing, and
graphical user interfaces (GUIs)
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1.2 Importance of Computer Graphics
• In Various Fields: Entertainment: Used extensively in
movies, video games, and virtual reality to create realistic
animations and visual effects.
• Education and Training: Enhances learning experiences
through visual simulations, e.g., in medical training or
engineering.
• Design and Manufacturing: CAD (Computer-Aided Design)
systems rely on graphics for designing products and
structures.
• Communication and Art: Vital for digital art, graphic design,
and advertising.
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1.3 History of Computer Graphics
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Early Developments:
1960s: The beginning of computer graphics with Ivan Sutherland’s
Sketchpad, one of the first graphical user interfaces.
1970s: Introduction of raster graphics, allowing for detailed images to be
displayed on screens.
Milestones:
1980s: Development of 3D graphics and the first computer-animated
films.
1990s: The rise of graphical user interfaces (GUIs) with the Windows and
Mac operating systems, making computers more accessible.
2000s and Beyond: Real-time rendering and the explosion of CGI in
movies and games, along with the advent of VR and AR technologies.

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1.4 Types of Computer Graphics
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•2D Graphics:
•Represent flat images without depth, such as illustrations, logos, and text.
•Used in graphic design, user interfaces, and simple animations.
•3D Graphics:
•Involves the creation of images with depth, allowing for realistic renderings
of objects and environments.
•Widely used in gaming, simulations, and virtual environments.
•Interactive Graphics:
•Graphics that respond to user input, like video games and interactive data
visualizations.

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3D Images Vs 2D Images
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2D Image 3D Images

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1.5 Components of Computer Graphics
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Hardware Components:
Graphics Processing Unit (GPU): Dedicated hardware for rendering images
and animations.
Monitors and Displays: Devices that output the visual content.
Input Devices: Tools like a mouse, graphics tablet, or 3D mouse used to
create and manipulate graphics.
Software Components:
Rendering Software: Tools like Blender, Maya, or Unity used to create and
animate 3D models.
Image Editing Software: Programs like Photoshop or GIMP for creating and
editing 2D images.

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1.6 Applications of Computer Graphics
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•Virtual Reality (VR) and Augmented Reality (AR): Creating
immersive environments for gaming, training, and simulations.
•Simulation and Visualization: Used in scientific research,
engineering, and architecture to model complex systems and
structures.
•Gaming and Entertainment: The backbone of modern video
games, animated movies, and special effects.
•Web and Mobile Graphics: Enhancing user experience in web
design and mobile applications.

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1.7 Future of Computer Graphics
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Trends:
AI in Graphics: Using machine learning to automate and enhance
graphics creation.
Photorealism: Achieving near-perfect realism in real-time rendering.
XR (Extended Reality): Combining VR, AR, and MR (Mixed Reality) for
more immersive experiences.
Challenges:
Computational Power: The need for more powerful hardware to
handle complex graphics tasks.
Ethical Considerations: Issues like deepfakes and the impact of hyper-
realistic graphics on society.

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2. Basics of Digital Imaging
2.1 Understanding Pixels and Resolution
• Pixels:
• Definition: The smallest unit of a digital image,
• typically square, that contains color and
• brightness information.
• Pixel Density: Measured in pixels per inch (PPI);
• higher PPI means finer detail.
• Image Resolution:
• Definition: The total number of pixels in an image, typically expressed
as width × height (e.g., 1920×1080).
• Impact on Quality: Higher resolution images have more detail and are
sharper, especially when enlarged.
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PIXELS VS RESOLUTION
Resolution
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2.2 Color Models and Representation
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RGB (Red, Green, Blue):
 Additive Color Model: Used in screens where colors are created by
combining red, green, and blue light.
 Color Depth: Measured in bits, defines how many colors can be represented
(e.g., 8-bit, 16-bit).
CMYK (Cyan, Magenta, Yellow, Key/Black):
 Subtractive Color Model: Used in printing; colors are created by subtracting
light using inks.
 Color Gamut: The range of colors that can be represented by the CMYK
model.
Other Models:
 HSV/HSB (Hue, Saturation, Value/Brightness): Used for color selection in
design tools.
 Grayscale: Images composed only of shades of gray, without color.

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2.3 Image Formats and Their Uses
JPEG (Joint Photographic Experts Group):
• Usage: Common for photos; supports millions of colors but uses lossy
compression.
• Advantages: Small file sizes.
• Disadvantages: Quality loss with each edit/save.
PNG (Portable Network Graphics):
• Usage: Ideal for web graphics, supports transparency (alpha channels).
• Advantages: Lossless compression; no quality loss.
• Disadvantages: Larger file sizes than JPEG.
GIF (Graphics Interchange Format):
• Usage: Best for simple graphics, animations; limited to 256 colors.
• Advantages: Supports animations and transparency.
• Disadvantages: Not suitable for photos due to limited color range.
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Raster Image Formats:

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Illustration
Gif Illustration
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Vector Image Formats:
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SVG (Scalable Vector Graphics):
•Usage: Best for logos, icons, and other designs that require
scaling.
•Advantages: Infinitely scalable without loss of quality.
•Disadvantages: Limited to simple graphics, not suitable for
detailed images.
Other Formats:
•TIFF (Tagged Image File Format): Often used in professional
photography and printing for its high quality.
•BMP (Bitmap): Uncompressed format, rarely used due to large file
sizes.

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3.0 Digital Image Processing
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Definition: The manipulation of digital images to improve quality or extract
information.
•Basic Operations:
•Cropping: Cutting out unwanted parts of an image.
•Resizing: Changing the dimensions of an image.
•Filtering: Applying effects like blur, sharpen, or noise reduction.
•Image Compression:
•Lossy vs. Lossless:
•Lossy Compression: Reduces file size by discarding some image data (e.g.,
JPEG).
•Lossless Compression: Reduces file size without any loss of image data (e.g.,
PNG).
Introduction to Image Processing:

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Photo Editing
3.1 Overview of Photo Editing
• Definition:
• Photo editing involves altering and enhancing images using various techniques to improve
their appearance or achieve a desired effect.
• Importance:
• Used in industries such as photography, advertising, media, and digital marketing to
produce professional-quality images.
• Common Uses:
• Portrait Retouching: Smoothing skin, removing blemishes, and adjusting lighting.
• Product Photography: Enhancing product images for e-commerce.
• Creative Effects: Applying artistic filters or combining images.
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3.2 Popular Photo Editing Software
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1. Adobe Photoshop:
Features: Industry standard for professional editing; offers advanced tools like layers,
masks, and filters.
Usage: Used for everything from simple edits to complex compositions.
Pros: Powerful and versatile with extensive plugin support.
Cons: Subscription-based, may have a steep learning curve.
GIMP (GNU Image Manipulation Program):
2. Features: Open-source alternative to Photoshop; includes most essential editing
tools.
Usage: Suitable for general photo editing and creative projects.
Pros: Free to use, community-supported with frequent updates.
Cons: Interface can be less intuitive than Photoshop.

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Canva
• Features: Web-based design tool for quick edits and graphic
design.
• Usage: Ideal for social media graphics and basic photo
enhancements.
• Pros: User-friendly, with many templates and elements
available.
• Cons: Limited in advanced editing capabilities.
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3.3 Basic Photo Editing Techniques
Cropping and Resizing:
• Cropping: Removing unwanted areas from the image to focus on the subject.
• Resizing: Changing the dimensions of the image while maintaining or adjusting aspect
ratio.
Color Correction:
• Brightness and Contrast: Adjusting lightness and darkness to enhance the overall look.
• Saturation and Hue: Modifying the intensity and tone of colors in the image.
• White Balance: Correcting the color cast to make the image look more natural.
Retouching and Healing:
• Spot Healing Brush: Removing minor blemishes, dust, and scratches.
• Clone Stamp Tool: Copying one part of the image over another to remove or replace
elements.
• Dodge and Burn: Lightening or darkening specific areas of the image to add depth and
focus.
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Filters and Effects:
• Pre-set Filters: Applying ready-made filters for quick
enhancements (e.g., sepia, black and white).
• Custom Effects: Creating and applying unique effects like
blur, vignette, and shadow.
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Getting Started with Adobe Photoshop
1. Introduction to Adobe Photoshop
• Overview:
• Adobe Photoshop is a powerful image editing software used by professionals and
hobbyists alike for photo retouching, graphic design, digital art, and more.
• Why Photoshop?:
• Versatility: It offers a wide range of tools for both basic and advanced editing.
• Industry Standard: Used globally across various industries, including photography, design,
and marketing.
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Downloading and Installing Adobe Photoshop
2.1 System Requirements
• Operating System: Ensure your system meets the minimum requirements for
running Photoshop.
• Windows: Windows 10 (64-bit) or later.
• Mac: macOS 10.14 (Mojave) or later.
• Processor: Intel® or AMD processor with 64-bit support; 2 GHz or faster processor.
• RAM: At least 8 GB (16 GB or more recommended).
• Graphics Card: GPU with DirectX 12 support; 2 GB GPU memory (4 GB
recommended).
• Storage: Minimum 4 GB of available hard-disk space for installation; additional free
space required during installation.
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2.2 Downloading Photoshop
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•Step 1: Adobe Creative Cloud Account
•Sign Up: Visit Adobe's website to create a free Adobe ID if you don't
have one.
•Subscription Plans: Choose a plan that suits your needs
(Photography plan, Single App, or All Apps).
•Step 2: Download Creative Cloud
•Installation: Download and install the Adobe Creative Cloud
desktop app from Adobe's website.
•Accessing Photoshop: Once installed, open Creative Cloud and
search for "Photoshop" in the apps section.

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Step 3: Install Photoshop
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•Installation: Click on the "Install" button next to
Adobe Photoshop.
•Wait for Download and Installation: The app will
download and install automatically. This may take
some time depending on your internet speed.

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2.3 First-Time Setup
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•Launching Photoshop: Open Adobe Photoshop from the Creative Cloud app
or directly from your desktop/start menu.
Interface Overview:
•Home Screen: Introduction to recent files, quick actions, and tutorials
available on the home screen.
•Workspace: Familiarize with the workspace layout, including the toolbar,
options bar, panels (like Layers, Color, etc.), and the canvas area.
•Customizing Your Workspace:
•Workspace Presets: Choose a workspace that fits your needs (Essentials,
Photography, Graphic and Web, etc.).
•Docking Panels: Learn how to move, dock, and arrange panels to create a
personalized workspace.

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3.1 Opening and Creating New Files
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•Opening Files: Demonstrate how to open an existing image or project
by selecting
File > Open.
•Creating a New Document:
•Presets: Use predefined document presets (e.g., for web, print, or
mobile).
•Custom Sizes: Set custom dimensions, resolution, and color mode.
•Artboards: Introduction to using artboards for multi-page designs.

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Illustration of Photoshop
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3.2 Introduction to the Toolbar
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Selection Tools:
Move Tool: For moving layers and objects.
Marquee Tools: For selecting rectangular or elliptical areas.
Lasso Tools: For freehand selection of objects.
Quick Selection and Magic Wand: For selecting areas based on color and
texture.
Editing Tools:
Brush Tool: For painting and retouching.
Eraser Tool: For removing parts of an image or layer.
Clone Stamp Tool: For duplicating parts of an image.

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Navigation Tools:
•Hand Tool: For panning around the canvas.
•Zoom Tool: For zooming in and out of the canvas.

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Simple Editing Task
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4.1 Importing an Image
Step-by-Step: Walk students through importing a sample image into
Photoshop.
4.2 Basic Edits
 Cropping: Use the Crop Tool to adjust the composition of the
image.
 Color Adjustment:
 Brightness/Contrast: Simple adjustments to enhance the
image.
 Hue/Saturation: Changing the overall color tone.
Saving Your Work:
Saving as PSD: Discuss the importance of saving in Photoshop’s native
format for preserving layers.
Exporting as JPEG/PNG: How to save the final image for web or print

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5. Troubleshooting Common Installation Issues
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•5.1 Installation Errors
•Error Messages: Address common installation errors, such as
"Installation Failed" or issues related to system compatibility.
•5.2 Activation Problems
•License Activation: Steps to troubleshoot if Photoshop
doesn’t activate correctly.
•5.3 Performance Issues
•Lagging and Freezing: Tips to optimize Photoshop
performance by adjusting Preferences > Performance settings.