Video & Scanning Overview

IT 130Web Graphics and Multimedia

Video Overview Video can be costly and time-

consuming to create

Video files can become extremely large

Many ready-made video clips available

Video Overview Video (like audio) requires analog

signal to be digitized

Video Overview Analog video (videotape) is linear –

it has a start, middle, and end

Digitized video allows random access

DVD is a good example

Video Overview Video file size

Frame rate (TV – 30 frames/second)

Image size

Color depth

Frames/second x image size x color depth / 8 = estimated file size of 1 second of video

Video Compression Two types of compression

Lossless – preserves the exact image (large file)

Lossy – eliminates data

Standards established for compression MPEG (Motion Pictures Experts Group) 20:1 compression ratio (1MB to 50KB)

Video Compression Compression software programs

Apple’s QuickTime (.MOV) Lossy compression with 5:1 to 25:1 ratios

Windows Media Player (.AVI) Uses Audio Video Interleave (AVI)

Format Examples

Video Compression Incorporating transitions Superimposing titles and animations Applying special effects Synchronizing sound with the video Applying filters for blurring,

morphing, etc.

Video on the Web Can be a drawback instead of an

asset

Animation or still images should be explored as an option

Quality vs. cost

Video on the Web Video transfer types

HTTP (HyperText Transfer Protocol) Small video clips

RTSP (Real-Time Streaming Protocol) Continuous-playing technology Large video files and live broadcasts

Video on the Web Streaming video very popular

Reduce start time significantly

Players RealPlayer Windows Media Player QuickTime Player

File formats (AVI and MPEG)

Video on the Web Digital Video Professionals

Association www.dvpa.com

Scanners Buyer’s guide

www.zdnet.com/special/filters/sc/scanner

TWAIN www.twain.org

TWAINQuestion: What is TWAIN an acronym for?

Answer: An image capture API for Microsoft Windows and Apple Macintosh operating systems. The standard was first released in 1992, and is currently ratified at version 1.9 as of January 2000. TWAIN is typically used as an interface between image processing software and a scanner or digital camera.

The word TWAIN is from Kipling's "The Ballad of East and West" - "...and never the twain shall meet...", reflecting the difficulty, at the time, of connecting scanners and personal computers. It was up-cased to TWAIN to make it more distinctive. This led people to believe it was an acronym, and then to a contest to come up with an expansion. None were selected, but the entry "Technology Without An Interesting Name" continues to haunt the standard. "

Scanning Demo HP ScanJet Scanner 5370C Series

$230