IMAGE
WHAT IS AN IMAGE?
Latin word IMAGO
Is an artifact that depicts or records visual perception,
Image represents information that needs to be seen and perceived.
Identifying the right image is important in multimedia applications.
TWO TYPES OF IMAGE
1. Raster image
typically are like photograph, which are captured by cameras,
sensors and others.
It reflects the real-world scene.
It is generally refers to a photo or drawing of something for art
purposes.
Raster image is composed of colored squares called pixels or
picture element.
tiny dots of individual colors that make up what you
see on your screen
the smallest component of a computer image.
Image Dimension
commonly measure images by inches when you have
pictures printed in Kodak or Fuji. Usually 3r 3x5 or 4r 4x5
inches.
reflected in the width and height of an image.
suitable for photo printing.
Image Resolution and Quality
The resolution describes how clear the image appears on
screen or in print.
Low-resolution images usually get distorted once
enlarged.
Screen resolution is defined as the number of pixels per
inch or PPI
Print resolution is defined as the number of dots per
inch or DPI.
Scaling -changing the size of an image without affecting the
total no.of pixels or resolution of an image.
Resizing – Changing the size of an image by removing a
particular amount of pixels.
PRINTVIEWING DISTANCE
PRINT SIZE PRINTVIEWING DISTANCE
PAPER SIZE at least 300 PPI
POSTER SIZE at least 200 PPI
LARGE FORMAT SIZE at least 72 PPI
RASTER IMAGE COMMON FORMAT
.JPEG -(Joint Photographic Experts Group)
.PNG (Portable Network Graphics
.GIF (Graphics Interchange Format)
.PSD (Photoshop Document)
.PNG (Portable Network Graphics
.GIF (Graphics Interchange Format)
.PSD (Photoshop Document)
POPULAR RASTER IMAGE EDITING SOFTWARE
Microsoft Paint
Adobe Photoshop
Corel Photo-Paint
Corel Paint Shop Pro
GIMP (GNU Image Manipulation Program)
2. Vector graphic.
depicts a digitally created image
comprised of objects such as shapes ,lines, ovals and curves.
In a Vector graphic ,each object is defined by a path.
An object can have many paths depending on the number of
objects it contains.
Objects have stroke and fill properties.
Stroke (or outline)properties are applied to the path of an
object
Fill properties are applied to the area enclosed by the path.
Stroke properties include weight ,color ,and style.
Weight property refers to the line thickness ,typically
measured in points.
Color property describes the color of the line.
Style property shows the different stroke styles like solid
line, dashed line, or dotted line.
Fill properties include color, gradient, and texture.
Color property describes the color of the object.
Gradient property describes the direction of the gradient
colors applied to the object whether linear,radial or
rectangular.
Texture property describes the design of the texture applied
on the object whether crumpled or woody.
Vector graphics are best used in multimedia applications when you
need to:
Represent a brand
Show something at a dissected view
Show something that cannot be captured with a digital
camera Show cartoon drawings
Represent space with a map
Show creative illustrations
The most common Vector graphic formats include:
AI (Adobe Illustrator File)
SVG (ScalableVector Graphic)
AI is a file drawn /colored inAdobe Illustrator.
SVG files are quite complex programmed files in XML. These files
usually require a special player to be viewed.
