Video on the Web
John H. Krantz
Hanover College
Outline
What is Video
Acquiring with a Digital Camera
Creating with ImageJ
Editing with QuickTime
Delivering in a Webpage
General Video Issues
Image size
Keep it small
Video Length
Shorter better
Image color depth
Normally full color
General Video Issues
Frame rate: recall difference between
apparent motion and flicker
10 to 15 is really fine for most cases
And best you can expect on web
Acquiring with a Digital Camera
Find format of your video camera:
mine is QuickTime
Can use digital zoom, original image
are much larger than movie images
Limited in time: mine are 30 sec or
size of disk
Image quality is good if presented in
original size
Creating with ImageJ
Stacks
Sequence of images to be played
Stack Menu
Can control frame rate under Options
Get AVI writer plugin to save as a movie
Editing with QuickTime Pro
Basics:
Tracks
Opens MOV, mpg, avi, mp3, etc.
Open more than one
Cut and Paste Operation
Adding Text to begging
Overlaying Text
Filtering in Save
Saving for Web
Format:
You must compress
Uncompressed will be very large
Very slow download
Duration
For same reason, keep it short
To Stream or Not to Stream
Steaming Regular Delivery
Starts sooner Wait for entire file
Can be large files Keep to small files
Can stop Keeps Speed
Generally low Better quality
quality
General Protocol
RTP/RTSP
Streaming vs. HTTP Fast Start
HTTP Fast Start is a feature of quick
time
Allows playing after part of file
downloaded
Fewer stops
No special software
Still keep files relatively small
Some loss of image quality
Embedding Movie in a Web Page