Computer Graphics Using “ Adobe Photoshop ” Introduction to E-Learning Center, DAD presents Workshop on Instructor: Mazhar

 The creation, display, editing and storage of Images, Illustrations and Typography with a computer. What is Computer Graphics ? CG

 Graphics technology & Images Editing  Design Principals  Composition and Layout  Color Theory and Principals  Typography  Image Format and Optimization Computer Graphics demands knowledge of

CG Graphics Technology Bitmap or Raster graphics Vector Graphics

Vector Graphic

Bitmap /Raster graphics  Image are broken up into a grid recorded individually,as Sequence of pixel  Works well for complex variations  Not flexible  Might need a lot of memory  Problems when scaled  Formats: BMP, GIF, JPEG, TIFF

vector graphics  Image are described as a series of lines or shapes  Works well for line art (CAD applications) and images with simple shapes and are flexible  Typically needs less memory  Data: Instructions for drawing lines and filling shapes Example: <line startcoord="x,01 y,01" endcoord="x, 20 y, 20" thickness="3"  Scalable, versatile

Image Resolution 18 DPI35 DPI72 DPI  The number of pixels along the height and width of a bitmap image is called the pixel dimensions of an image.  The resolution of an image is determined by the number of pixels per inch (dpi, ppi).

Image Resolution 18 DPI

Image Resolution 35 DPI

72 DPI Image Resolution

Design Principals

Composition and Layout

Color Theory

 Red, Green, Blue  Additive synthesis  Color monitors, Projectors  Perceived color is white when each component has full intensity, perceived color is black when each component has no intensity Color Theory RGB Mode

 Cyan, Magenta, Yellow Black  Subtractive synthesis  Color printers  Perceived color is white when each component has no intensity, perceived color is black when each component has full intensity  Printing press use four-color printing Color Theory CMYK Mode

Color Theory HSV mode  Hue, Saturation, Value  User oriented, previous ones were hardware oriented  Use color perception quantities: hue, saturation and value  Hue defines color  Saturation refers how far color is from a gray of equal intensity  Value defines the lightness/brightness of the color

Color Theory

Typography

Image Format Optimization