Multimedia in Web

1 / 14

# Multimedia in Web - PowerPoint PPT Presentation

Multimedia in Web Images A Picture Tells A Thousand Words Forms of Images Photograph Painting Symbol Logo Flag Map Diagram Functions Provide facts Explain a process Set a mood Evoke an idea Pinpoint location Illustrate relationships Digitalization & Pixel

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about 'Multimedia in Web' - Jimmy

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

### Multimedia in Web

Images

A Picture Tells A Thousand Words
• Forms of Images
• Photograph
• Painting
• Symbol
• Logo
• Flag
• Map
• Diagram
• Functions
• Provide facts
• Explain a process
• Set a mood
• Evoke an idea
• Pinpoint location
• Illustrate relationships
Numeric Representation & RGB
• 16 digits instead of 10
• 09 & AF
• Base 16 can represent 0 to 255 color scales
• Two digits of hexadecimal numbers
• 00 in Hex.  0 in decimal
• FF in Hex. 255 in decimal
RBG Colors

Sample Colors

Color Chart: http://quasar.unl.edu/tutorials/rgb.html

Color Depth
• 16-bit vs. 8-bit
• 30,000 colors vs. 256 colors
• Web-safe colors (No longer a concern?)
Compression
• Purpose
• Reduce file size for transmission
JPEG
• Photographs
• From 255 levels of color and brightness to lower levels
• Group pixels into blocks. Adjacent and similar color and brightness  block or average
• Example: The next slide
Example
• 9 values with 3 different colors for 9 pixels  1 value for the average and 2 values for difference from the average for other colors
• A string of values such as #FF3399, #FF3399, #FF3399, #CC3399 … for all 9 pixels  #FF3399 as the average, 2 values for other colors differentiating from the average
GIF
• For line drawings
• Reduce color depth of every pixel to 8 bits or less
• Repeated colors across a row of pixels are reduce to the color value, the value of the repetition, other instructions.
Vector Graphics
• Web images use bitmapped format or pixel-by-pixel
• Collection of lines & shapes defined by mathematical formula (e.g. Flash)
Source of Image
• Scanned image
• Digital camera
• Original artwork
• Web site
• CD-ROM
• Clip art
• Stock photograph
Photoshop
• Explore editing, compressing, & saving for Web
Image & HTML
• IMG tag
• Linking with image
• Image map